Introduction

NOTE: For specifications, refer to the Specifications For 3176C & 3196 Marine Engines, RENR1231. If the Specifications in RENR1231 are not the same as in the Systems Operation, Testing & Adjusting, look at the printing date on the back cover of each book. Use the Specifications given in the book with the latest date.

Troubleshooting

To troubleshoot engine problems refer to Troubleshooting, 3176C & 3196 Marine Engines SENR1170.

Electronic Control System

Diagnostic Codes

For an explanation of each diagnostic code see the 3176C & 3196 Marine Engines Troubleshooting.

Active Diagnostic Codes

Diagnostic codes are used by the 3176C & 3196 Marine Engines System to warn the vessel operator of a problem and indicate to the service technician the nature of the problem. Some codes are used only to record an event and do not indicate problems that need repair.

An ACTIVE diagnostic code represents a problem that should be investigated and corrected AS SOON AS POSSIBLE. Repairing the cause of an ACTIVE code will cause the code to be cleared.

When an ACTIVE code is generated, the diagnostic lamp will turn ON and remain ON, blinking every five seconds. If the condition generating the fault occurs only for a brief moment, the lamp will go OFF after five seconds and the code will be LOGGED.

There are a few codes which are not a response to a performance problem, but merely record an event such as 01, 35, 41, 47 and 55. In these cases troubleshooting is not required.

Some Diagnostic Codes cause the 3176C & 3196 Marine Engines System to make major changes in engine operation or limits, as a result of the code being generated.

Logged Diagnostic Codes And Events

When the ECM generates a diagnostic code, it usually logs the code in permanent memory within the ECM. The ECM has an internal diagnostic clock and will record the hour EACH time a code is logged. Knowing when and how often the code was generated can be a valuable indicator when troubleshooting intermittent problems. Logged codes can be retrieved or erased using an electronic service tool. They can be a valuable indicator when troubleshooting intermittent problems.

* Diagnostic Codes that are logged repeatedly may indicate a problem that needs special investigation. Codes that are logged only a few times and do not result in operator complaints, may not need attention until a scheduled maintenance interval.

To troubleshoot a Logged Diagnostic Code, refer to the "Troubleshooting Diagnostic Codes" section in the 3176C & 3196 Marine Engines Troubleshooting. If symptoms continue, refer to "Troubleshooting Without A Diagnostic Code" section in the 3176C & 3196 Marine Engines Troubleshooting.

* The most likely cause of an intermittent problem is a faulty connection or damaged wiring. Next likely is a component failure (sensor or switch for example). Least likely is the ECM itself.

Electronic Service Tools

The Caterpillar Service Tools for the 3176C & 3196 Marine Engines Electronic Control System are designed to help the service technician:

* Diagnose Faults And System Problems

* Calibrate Sensors

* Program Parameters

* Read Trip Data

* Read Status Of Sensors/Switches

The 3176C & 3196 Marine Engines require an Electronic Control Analyzer and Programmer (ECAP) or PC based Cat ET to communicate with the 3176C & 3196 Marine Engines Electronic Control Module.

Installation/Removal Of The Speed/Timing Sensor

Engine-Front Right Side
(1) Backup speed/timing sensor. (2) Primary speed/timing sensor. (3) Front gear cover.

1. Disconnect the P20/J20 and P44/J44 connectors from the speed/timing sensor. Inspect for corrosion, bent or missing pins and sockets, and mismating, broken wires, etc.

2. Remove the primary speed/timing sensor (2) and the backup speed/timing sensor (1) from front gear cover (3).

3. Examine the plastic end of the sensor for signs of wear or contaminants such as metal filings. The plastic end of the speed/timing sensor should have no contaminants or show no wear [greater than 0.051 mm (.0020 in) from its face].

4. Use a screwdriver to carefully pry the plastic sensor end to the fully Extended position [approximately 4.775 mm (.1880 in) beyond the metal housing of the sensor].

5. Gently push in on the plastic end of the sensor. The plastic end should be firm and resist movement in the retract direction. If there is no resistance replace the sensor.

Locating Top Center
(4) Bolts (two-6V5219). (5) Cover. (6) Flywheel housing.

6. Remove two bolts (4) and remove cover (5) from the flywheel housing (6) to open the hole for engine turning.

7. Put one of the 6V5219 bolts (4) in the timing hole located approximately 127 to 152 mm (5 to 6 in) above the hole in the flywheel housing for engine turning. Use the 9S9082 Engine Turning Tool and a 1/2 inch drive ratchet wrench to turn the engine flywheel in the direction of normal engine rotation (counterclockwise when viewed from the flywheel end) until the timing bolt engages with the threaded hole in the flywheel.

NOTE: The No. 1 piston must be at either top center of the compression stroke or top center of the exhaust stroke.

8. To install the speed/timing sensors, first perform the sensor inspections described in steps 3 through 6.

9. If the sensor end is not fully extended, use a screwdriver to carefully pry the plastic sensor end to the fully EXTENDED position [approximately 4.775 mm (.1880 in) beyond the metal housing of the sensor].

10. Examine the O-ring seal at the base of the sensor threads. If it is missing or damaged, install a new O-ring seal.

11. Install the speed/timing sensors into the front gear cover. Tighten to a torque of 40 ± 5 N·m (30 ± 4 lb ft)

12. Connect the P20/J20 and P44/J44 connectors for the speed/timing sensors near the coolant inlet pipe on the top of the engine.

NOTE: Be sure that the P20/J20 and P44/J44 lock ring is properly "locked".

NOTE: The electronic injection timing must be recalibrated after reinstallation of the speed/timing sensor (see the topic, Electronic Injection Timing Troubleshooting).

Throttle Position Sensor Adjustment

The Throttle Position Sensor (TPS) is used to provide a throttle signal to the Electronic Control Module (ECM). Sensor output is a constant frequency signal whose pulse width varies with throttle position. This output signal is referred to as either "Duty Cycle" or a "Pulse Width Modulated (PWM)" signal and is expressed as a percentage. When correctly adjusted, the TPS will produce a "Duty Cycle" signal of 5 to 10 percent at the low idle throttle position and 90 to 95 percent at the maximum throttle position. This signal is translated by the ECM into a "Throttle Position" signal of zero percent at low idle and 100 percent at maximum throttle.

Throttle Sensor

Throttle Sensor

Calibration of the Throttle Sensor is done by the ECM. The correct calibration can be displayed with the electronic service tool. The correct percent throttle (governor control movement) is displayed as zero percent with the throttle completely released, and 100 percent with the throttle completely depressed.

Throttle Sensor

Calibration of the Throttle Sensor is done by the ECM. The correct calibration can be displayed with the electronic service tool. The correct percent throttle (governor control movement) is displayed as 8 percent with the throttle completely released, and 92 percent with the throttle completely depressed.

Fuel System

Fuel System Components
(1) Fuel temperature sensor. (2) Adaptor (siphon break and regulator). (3) Fuel line (ECM to fuel filter base). (4) Fuel supply and return manifold. (5) Fuel line (filter base to supply manifold). (6) Fuel line (fuel transfer pump to ECM). (7) ECM.

(8) Fuel inlet (to fuel transfer pump). (9) Fuel transfer pump. (10) Fuel outlet (from fuel transfer pump).

Fuel System Components
(3) Fuel line (ECM to fuel filter base). (7) Fuel line (filter base to supply manifold). (11) Fuel priming pump. (12) Fuel pressure sensor. (13) Fuel filter.

Either too much fuel or not enough fuel for combustion can be the cause of a problem in the fuel system. Many times work is done on the fuel system when the problem is really with some other part of the engine. The source of the problem is difficult to find, especially when smoke comes from the exhaust. Smoke that comes from the exhaust can be caused by a defective unit injector, but it can also be caused by one or more of the reasons that follow:

* Not enough air for good combustion.

* An overload at high altitude.

* Oil leakage into combustion chamber.

* Not enough compression.

* Fuel injection timing incorrect.

* Cold engine operation.

* Low octane fuel.

Fuel System Inspection

A problem with the components that send fuel to the engine can cause low fuel pressure. This can decrease engine performance.

1. Check the fuel level in the fuel tank. Look at the cap for the fuel tank to make sure the vent is not filled with dirt.

2. Check all fuel lines for fuel leakage. Be sure none of the fuel lines have a restriction or a defective bend. Verify that the fuel return line has not collapsed in the sections subject to heat.

3. Install a new fuel filter.

4. Remove any air that may be in the fuel system. Refer to Fuel Priming Procedure in this service manual.

Fuel Transfer Pump

With the engine operating at rated rpm and load condition, the fuel transfer pump moves fuel through the ECM, fuel filter base, fuel supply manifold, and return manifold. An orificed valve in the return fuel manifold restricts fuel flow. A pressure regulation valve is in the transfer pump. The normal fuel pressure is 500 kPa (72 psi) at rated rpm.

If the fuel pressure is low, a fault will be logged. Stop and replace the fuel filter. Make sure the fuel lines are not plugged or damaged.

Start the engine and again check the fuel pressure. If fuel pressure is still low, check the fuel regulating valve in the fuel transfer pump.

If the fuel pressure is high 690 kPa (100 psi) or above, stop the engine. Remove the orificed valve from the adaptor. The valve is directly behind the return line fitting. Check for debris plugging the orifice holes near the tip. If plugged, flush any remaining debris from the return passage, and check source of debris. If not plugged, check for plugged return fuel line. If no obstructions were found, check the fuel transfer pump regulating valve for debris or rust, causing stickiness.

Fuel Pressure

To check the fuel transfer pump pressure, remove the fuel pressure sensor from the fuel filter base. Install a pressure indicator, and start the engine.

The 1U5470 Engine Pressure Group can be used to check engine fuel pressure.

This tool group has a indicator to read fuel pressure to the fuel supply manifold. Special Instruction, SEHS8907 is with the tool group and gives information for its use.

1U5470 Engine Pressure Group

Fuel Priming Procedure

Siphon Break Adaptor (Right Hand Service)
(1) Adaptor. (2) Air purge port plug. (3) Fuel inlet line.

NOTE: Refer to the Operations & Maintenance Manual for the correct procedure for fuel priming.

NOTE: Each time the fuel system is run out of fuel or air is introduced into the system the following procedure must be followed.

1. After fuel is added to the fuel tank, remove air purge port plug (2) in fuel adapter at the air purge port.

2. Use the hand priming pump to pump fuel into the system. Stop pumping when fuel appears at the port.

3. Plug the air purge port. Continue pumping until a strong pressure is felt on the pump, and you hear a "click" from the fuel filter base. This pressurizes the system with approximately 345 kPa (50 psi) and dramatically reduces engine crank time. When finished, LOCK THE PUMP in the bottom position to avoid possible damage to the pump.

4. Crank the engine as soon as you can after pressurizing the system. It should start within 15 seconds. If not started after 30 seconds, stop and wait two minutes. Repeat Step 3 to repressurize the system, and crank engine again for up to 30 second.

Unit Injector Adjustment

Injector Mechanism
(1) Rocker arm. (2) Adjusting screw. (3) Locknut.

To make an adjustment to the unit injector, turn the adjusting screw in the rocker arm. Unit injector adjustment can be make by using the procedure that follows:

1. Put No. 1 piston at top center (TC) on the compression stroke. See the topic, Finding Top Center Position For No. 1 Piston.

2. Turn the unit injector adjusting screw (2) CW (clockwise) until contact is made with the unit injector.

3. Turn the adjusting screw CW (clockwise) an additional 180 degrees (1/2 turn).

4. Hold the adjusting screw in this position and tighten the locknut (3) to a torque of 55 ± 10 N·m (41 ± 7 lb ft).

5. Make an adjustment to the unit injectors on cylinders 3, 5, and 6.

6. Remove the timing bolt and turn the flywheel 360 degrees in the direction of engine rotation (counterclockwise). This will put No. 1 piston at top center (TC) on the exhaust stroke.

7. Make an adjustment to the unit injectors on cylinders 1, 2, and 4.

8. Remove the timing bolt from the flywheel when all the unit injector adjustments have been made, and reinstall the timing cover.

Static Check Of The Timing Gear Position Used To Reference Electronic Injection Timing / Front Gear Group Alignment

Front Gear Group (with front cover removed)
(1) Camshaft gear / timing reference ring. (2) Timing marks. (3) Idler gear. (4) Crankshaft gear.

The basis for correct fuel injection timing and valve mechanism operation is determined by the timing reference ring and the alignment of the front gear group. The timing reference ring is located on the end of the camshaft group, and it is used to measure crankshaft rotation. During installation of the front gear group, timing marks (2) on idler gear (3) must be in alignment with the timing marks on crankshaft gear (4) and the timing marks on camshaft gear (1). For a complete removal and installation procedure of the front gear group, see the topic, Front Gear Group, in the Disassembly & Assembly module.

NOTE: It is possible to install the Timing Reference Ring backwards. If this occurs, the engine will not start.

Check for proper alignment of the timing reference ring (1) on the camshaft assembly. Inspect the key between the timing reference ring and the camshaft gear. Check the timing ring teeth. The teeth should not be defaced, and should have sharp clean edges and be free of contaminants.

NOTE: The electronic injection timing must be calibrated after re-assembly of the front gear train. Refer to the topic Engine Speed/Timing Sensor in the Troubleshooting manual, SENR1170, for information on the engine timing procedure.

Finding Top Center Position For No. 1 Piston

Locating Top Center
(1) Bolts (two-6V5219). (2) Cover. (3) Flywheel housing.

1. Remove two bolts (1) and remove cover (2) from the flywheel housing (3) to open the turning hole.

2. Put one of the 6V5219 Bolts (1) in the timing hole located approximately 127 to 152 mm (5 to 6 in) above the turning hole in the flywheel housing. Use the 9S9082 Engine Turning Tool and a 1/2 inch drive ratchet wrench to turn the engine flywheel in the direction of normal engine rotation (counterclockwise when viewed from the flywheel end) until the timing bolt engages with the threaded hole in the flywheel.

NOTE: If the flywheel is turned beyond the point that the timing bolt engages in the threaded hole, the flywheel must be turned opposite normal engine rotation approximately 30 degrees. Then turn the flywheel in the direction of normal rotation (counterclockwise) until the timing bolt engages with the threaded hole. The reason for this procedure is to make sure the play is removed from the gears when the No. 1 piston is put on top center.

3. Remove the front valve cover from the engine.

4. The inlet and exhaust valves for the No. 1 cylinder are fully closed if No. 1 piston is on the compression stroke and the rocker arms can be moved by hand. If the rocker arms cannot be moved and the valves are slightly open, the No. 1 piston is on the exhaust stroke.

NOTE: When the actual stroke position is identified, and the other stroke position is needed, it is necessary to remove the timing bolt from the flywheel, turn the flywheel counterclockwise 360 degrees, and reinstall the timing bolt.

Electronic Injection Timing Troubleshooting

Electronic injection timing troubleshooting is required if the electronic injection timing is inconsistent or it will not calibrate correctly. If either of these conditions are present, refer to the topic, Engine Timing Calibration Procedures in the 3176C & 3196 Marine Engines Troubleshooting.

Engine Speed Measurement

9U7400 Multitach Group

The 9U7400 Multitach Group can measure engine speed from a magnetic pickup on the flywheel housing. It also has the ability to measure engine speed from visual engine parts in rotation.

Operators Manual, NEHS0605 is with the 9U7400 Multitach Group and gives instructions for the test procedure.

Air Inlet And Exhaust System

Restriction Of Air Inlet And Exhaust

There will be a reduction of horsepower and efficiency of the engine if there is a restriction in the air inlet or exhaust system.

Air flow through the air cleaner must not have a restriction (negative pressure difference measurement between atmospheric air and air that has gone through air cleaner) of more than 7.5 kPa (30 inches of H₂O) with a used or plugged air cleaner element. Air flow through the air cleaner must not have a restriction (negative pressure difference measurement between atmospheric air and air that has gone through air cleaner) of more than 3.7 kPa (15 inches of H₂O) with a new air cleaner element.

Back pressure from the exhaust (pressure difference measurement between exhaust at outlet elbow and atmospheric air) must not be more than 6.8 kPa (27 inches of H₂O).

Measurement Of Pressure In Inlet Manifold

The efficiency of an engine can be checked by making a comparison of the pressure in the inlet manifold with the information given in the TMI (Technical Marketing Information), or Fuel Setting And Related Information Fiche. This test is used when there is a decrease of horsepower from the engine, yet there is no real sign of a problem with the engine.

The correct pressure for the inlet manifold is given in the TMI (Technical Marketing Information), or Fuel Setting And Related Information Fiche. Development of this information is done with these conditions:

a. 99 kPa (29.3 inches of Hg) (DRY) barometric pressure.

b. 25°C (77°F) outside air temperature.

c. 35 API rated fuel.

On a turbocharged and aftercooled engine, a change in fuel rating will also change horsepower and the pressure in the inlet manifold. If the fuel is rated above 35 API, pressure in the inlet manifold can be less than given in the TMI (Technical Marketing Information), or Fuel Setting And Related Information Fiche. If the fuel is rated below 35 API, the pressure in the inlet manifold can be more than given in the TMI (Technical Marketing Information), or Fuel Setting And Related Information Fiche. Be Sure That The Air Inlet Or Exhaust Does Not Have A Restriction When Making A Check Of Pressure In The Inlet Manifold.

Pressure Test Location On Inlet Manifold
(1) Plug.

To measure the inlet manifold pressure, remove plug (1) from the inlet manifold. Use the 1U5470 Engine Pressure Group to check the pressure in the inlet manifold.

1U5470 Engine Pressure Group

This tool group has a indicator to read pressure in the inlet manifold. Special Instruction, SEHS8907 is with the tool group and gives instructions for its use.

Exhaust Temperature

Use the 123-6700 Infrared Thermometer to check exhaust temperature. The Operator's Manual, NEHS0630, for the 123-6700 Infrared Thermometer gives complete operating and maintenance instructions for this tool.

Aftercooler Systems

Inlet Manifold Pressure

Normal inlet manifold pressure with high exhaust temperature can be caused by cooler core fin blockage. Clean the cooler core fins, see Visual Inspection for the cleaning procedure to use.

Low inlet manifold pressure and high exhaust manifold temperature can be caused by any of the conditions that follow:

1. A plugged air cleaner. Clean or replace the air cleaner as needed.

2. A blockage in the air lines between the air cleaner and turbocharger. All restrictions must be removed.

3. Cooler core leakage. Pressure test the cooler core, see Aftercooler Core Leakage for the correct procedure to use and repair or replace parts as needed.

4. Leakage from the pressure side of the induction system. Check and repair leaks.

5. Inlet manifold leak. Check for loose, missing and damaged fittings or plugs. Also check the manifold to cylinder head gaskets.

Aftercooler Condensate Drain Valve

An aftercooler condensate drain system is provided with the 3176C & 3196 Marine Engines. Moisture can collect in the air inlet/aftercooler housings and pool in the bottom of the housings under the following certain conditions: cold sea water, warm, humid air, and when the engine is stopped. If enough water condenses in the housing, it could run down the inlet ports into the cylinders. Trying to start the engine would result in a hydraulic lock.

Ledges have been cast around the inlet ports on the 3176C & 3196 Marine Engines to prevent the condensed water from draining into the ports. One drain on each side of the aftercooler core allows water to drain from the housings. The two drains are plumbed together and run to a check valve. The check valve is open when the engine is stopped to allow the moisture to drain. When boost is present, the drain valve closes.

All 3176C & 3196 Marine Engines are equipped with the condensate drain, however most engines will not normally see conditions that will cause condensation. Nevertheless, the drain and valve should be regularly inspected to insure proper operation in the event that it is needed. The volume of water that may drain from the aftercooler housing will be small and any additional installation work is unnecessary. Do not install a hose to the end of the drain that could be submerged in the bilge water or collect debris.

The condensate drain is standard on all 3176C & 3196 Marine Engines and is installed at the rear of the aftercooler housings. This is the correct location for an engine rear down application. If the installation is a front down, the condensate drain must be relocated to the front of the aftercooler housings.

During engine operation the boost pressure forces the plunger down to close the orifice. The plunger must close against the seat at pressure of 27.5 kPa (4 psi). When the engine is stopped the absence of boost pressure allows the plunger to raise to it's open position which allows condensation from the aftercooler to drain out. It is important that the plunger move freely to close off the system when the engine is running and to allow the moisture to escape from the aftercooler when the engine is stopped. Remove the valve from the adapter and inspect to determine if the plunger moves freely. Residue from normal engine operation could cause the valve to become sticky. If the valve does not move easily, use solvent to clean the valve.

Remove the drain lines and check for plugging in the drain lines. Pressure air or a small diameter flexible rod can be used to clean the lines.

Crankcase (Crankshaft Compartment) Pressure

Pistons or rings that have damage can be the cause of too much pressure in the crankcase. This condition will cause the engine to run rough. There will also be more than the normal amount of fumes (blowby) coming from the crankcase breather. The breather can then become restricted in a very short time, causing oil leakage at gaskets and seals that would not normally have leakage. Other sources of blowby can be worn valve guides or turbocharger seal leakage.

8T2700 Indicator Group

The 8T2700 Indicator Group is used to check the amount of blowby. The test procedure is in Special Instruction, SEHS8712.

Compression

An engine that runs rough can have a leak at the valves, or have valves that need adjustment. Removal of the head and inspection of the valves and valve seats is necessary to find those small defects that do not normally cause a problem. Repair of these problems is normally done when reconditioning the engine.

Cylinder Head

The cylinder head has valve seat inserts, valve guides and bridge dowels that can be removed when they are worn or have damage. Replacement of these components can be made with the tools that follow. Most of the tools are part of the 1U9654 Head Repair Tool Group.

NOTE: The Disassembly & Assembly moduel contains a complete procedure for removing and installing the cylinder head components.

Valves

For valve removal and installation use the 5S1330 Valve Spring Compressor Assembly or 4C6726 Valve Spring Compressor Group, and the 5S1332 Valve Keeper Inserter.

NOTE: A 1U7798 Hammer and 1U7794 Shaft Assembly are used to remove and install the valve seat inserts and valve guides.

Valve Seat Inserts

Tools needed to remove and install the valve seat inserts are: 1U9166 Valve Seat Extractor for inlet valves, 1U9167 Valve Seat Extractor for exhaust valves, 1U9170 Valve Seat Driver, and 1U9706 Plate (for exhaust seats).

Valve Guides

Tools needed to remove and install the valve guides are the 1U9168 Valve Guide Collar (Stop) and the 1U9169 Valve Guide Driver.

Checking Valve Guide Bores

Use the 5P3536 Valve Guide Gauge Group to check the bore of the valve guides. Special Instruction, GMG02562 gives complete and detailed instructions for use of the 5P3536 Valve Guide Gauge Group.

Valve Lash Setting

Show/hide table

To prevent possible injury, do not use the starting motor to turn the flywheel. Hot engine components can cause burns. Allow additional time for the engine to cool before measuring valve lash. The 3176C & 3196 Marine Engines use high voltage to the unit injectors. Do not come in contact with the injector terminals while the engine is running. Disconnect J91P91. Refer to the Schematic, SENR1171, for the location of J91P91.

NOTE: Valve lash is measured between the rocker arm and the bridge for the valves.

NOTE: When the valve lash is checked, adjustment is Not Necessary if the measurement is in the range given in the chart for Valve Lash Check: Engine Stopped. If the measurement is outside this range, adjustment is necessary. See the chart for Valve Lash Setting: Engine Stopped, and make the setting to the nominal (desired) specifications in this chart.

Cylinder And Valve Location. (A) Exhaust Valve. (B) Inlet Valve.

To make an adjustment to the valve lash, turn the adjustment screw in the rocker arm. Valve lash adjustments can be made by using the procedure that follows:

1. Put No. 1 piston at top center (TC) on the compression stroke. See the topic, Finding Top Center Position For No. 1 Piston.

Inlet Valve Adjustment
(1) Inlet rocker arm. (2) Adjustment locknut.

Exhaust Valve Adjustment
(3) Exhaust rocker arm. (4) Adjustment locknut.

2. Make an adjustment to the valve lash on the inlet valves for cylinders 1, 2 and 4. Make an adjustment to the valve lash on the exhaust valves for cylinders 1, 3, and 5.

3. After each adjustment, tighten the nut for valve adjustment screw to a torque of 25 ± 7 N·m (18 ± 5 lb ft), and check the adjustment again.

4. Remove the timing bolt and turn the flywheel 360 degrees in the direction of engine rotation. This will put No. 6 piston at top center (TC) on the compression stroke. Install the timing bolt in the flywheel.

5. Make an adjustment to the valve lash on the inlet valves for cylinders 3, 5, and 6. Make an adjustment to the valve lash on the exhaust valves for cylinders 2, 4, and 6.

6. After each adjustment, tighten the nut for valve adjustment screw to a torque of 25 ± 7 N·m (18 ± 5 lb ft), and check the adjustment again.

7. Remove the timing bolt from the flywheel when all adjustments to the valve lash have been made.

Lubrication System

One of the problems in the list that follows will generally be an indication of a problem in the lubrication system for the engine.

* Too Much Oil Consumption

* Oil Pressure Is Low

* Oil Pressure Is High

* Too Much Bearing Wear

* Increased Oil Temperature

Too Much Oil Consumption

Oil Leakage On Outside Of Engine

Check for leakage at the seals at each end of the crankshaft. Look for leakage at the oil pan gasket and all lubrication system connections. Check to see if oil comes out of the crankcase breather. This can be caused by combustion gas leakage around the pistons. A dirty crankcase breather will cause high pressure in the crankcase, and this will cause gasket and seal leakage.

Oil Leakage Into Combustion Area Of Cylinders

Oil leakage into the combustion area of the cylinders can be the cause of blue smoke. There are four possible ways for oil leakage into the combustion area of the cylinders:

* Oil leakage between worn valve guides and valve stems.

* Worn or damaged piston rings, or dirty oil return holes.

* Compression ring and/or intermediate ring not installed correctly.

* Oil leakage past the seal rings in the impeller end of the turbocharger shaft.

Too much oil consumption can also be the result if oil with the wrong viscosity is used. Oil with a thin viscosity can be caused by fuel leakage into the crankcase, or by increased engine temperature.

Measuring Engine Oil Pressure

An oil pressure indicator that has a defect can give an indication of low or high oil pressure.

1U5470 Engine Pressure Group

The 1U5470 Engine Pressure Group can be used to measure the pressure in the system independent of the engines electronic sensors. This tool group has a indicator to read pressure in the oil manifold. Special Instruction, SEHS8907 is with the tool group and gives instructions for its use.

Show/hide table

Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

Engine-Right Side (Typical Example)
(1) Plug. (2) Plug.

Oil pressure to the camshaft and main bearings should be checked on the side of the cylinder block at oil gallery plugs (1) or (2). Install the 1U5470 Engine Pressure Group into this opening. With the engine at operating temperature (using SAE 15W40 oil), under full load condition, oil pressure should be 275 to 414 kPa (40 to 60 psi). With the engine at operating temperature (using SAE 15W40 oil), at 600 to 800 rpm low idle, minimum oil pressure is 68 kPa (10 psi).

Oil Pressure Is Low

Crankcase Oil Level

Check the level of the oil in the crankcase. Add oil if needed. It is possible for the oil level to be too far below the engine oil pump supply tube. This will cause the engine oil pump not to have the ability to supply enough lubrication to the engine components.

Engine Oil Pump Does Not Work Correctly

The inlet screen of the supply tube for the engine oil pump can have a restriction. This will cause cavitation (low pressure bubbles suddenly made in liquids by mechanical forces) and a loss of oil pressure. Air leakage in the supply side of the engine oil pump will also cause cavitation and loss of oil pressure. If the bypass valve for the engine oil pump is held in the open (unseated) position, the lubrication system cannot get to maximum pressure. Oil pump gears that have too much wear will cause a reduction in oil pressure.

Engine Oil Filter Bypass Valve

If the bypass valve for the engine oil filter is held in the open position (unseated) because the engine oil filter has a restriction, a reduction in oil pressure can result. To correct this problem, remove and clean the bypass valve and bypass valve bore. Install a new engine oil filter to be sure that no more debris makes the bypass valve stay open.

Too Much Clearance At Engine Bearings Or Open Lubrication System (Broken Or Disconnected Oil Line Or Passage)

Components that are worn and have too much bearing clearance can cause oil pressure to be low. Low oil pressure can also be caused by an oil line or oil passage that is open, broken or disconnected.

Piston Cooling Jets

When engine is operated, the piston cooling jets direct oil toward the bottom of the piston to cool the piston and also provide lubrication for the piston pin. If a piston cooling jet is broken, plugged or installed wrong, seizure of the piston will occur in a very short period time.

Oil Pressure Is High

Oil pressure will be high if the bypass valve for the engine oil pump cannot move from the closed position.

Too Much Bearing Wear

When some components of the engine show bearing wear in a short time, the cause can be a restriction in an oil passage.

If the indicator for oil pressure shows enough oil pressure, but a component is worn because it cannot get enough lubrication, look at the passage for oil supply to the component. A restriction in a supply passage will not let enough lubrication get to a component, and this will cause early wear.

Increased Oil Temperature

With the engine at operating temperature (using SAE 15W40 oil), the maximum oil temperature is 110°C (230°F). This temperature is from or after the engine oil cooler.

Look for a restriction in the oil passages of the engine oil cooler. If the engine oil cooler has a restriction, the oil temperature will be higher than normal when the engine is operated. The oil pressure of the engine will not get low just because the engine oil cooler has a restriction.

Also check the oil cooler bypass valve to see if it is held in the open position (unseated). This condition will let the oil through the valve instead of the engine oil cooler, and oil temperature will increase.

Indicators For Oil Pressure

An oil pressure indicator or a sender that has a defect can give an indication of low or high oil pressure.

The 1U5470 Engine Pressure Group can be used to make a comparison with instrument panel indicators.

Cooling System

This engine has a pressure type cooling system. A pressure type cooling system gives two advantages. The first advantage is that the cooling system can have safe operation at a temperature that is higher than the normal boiling (steam) point of water. The second advantage is that this type system prevents cavitation (low pressure bubbles suddenly made in liquids by mechanical forces) in the water pump. With this type system, it is more difficult for an air or steam pocket to be made in the cooling system.

The cause for increased engine temperature is generally because regular inspections of the cooling system were not made. Make a visual inspection of the cooling system before a test is made with test equipment.

Visual Inspection Of The Cooling System

1. Check coolant level in the cooling system.

2. Look for leaks in the system.

NOTE: Water pump seals. A small amount of coolant leakage across the surface of the "face-type" seals is normal, and required, to provide lubrication for this type of seal. A hole is provided in the water pump housing to allow this coolant/seal lubricant to drain from the pump housing. Intermittent leakage of small amounts of coolant from this hole is not an indication of water pump seal failure. Replace the water pump seals only if a large amount of leakage, or a constant flow of coolant is observed draining from the water pump housing. See the topic, Water Pump, Disassemble & Assemble, for a complete description of replacement of the water pump seals.

3. Look for bent radiator fins. Be sure that air flow through the radiator does not have a restriction.

4. Inspect the drive belt for the fan.

5. Check for damage to the fan blades.

6. Look for air or combustion gas in the cooling system.

7. Inspect the filler cap and the surface that seals the cap. This surface must be clean.

Testing The Cooling System

Remember that temperature and pressure work together. When a diagnosis is made of a cooling system problem, temperature and pressure must both be checked. Cooling system pressure will have an effect on cooling system temperatures. For an example, look at the chart to see the effect of pressure and height above sea level on the boiling (steam) point of water.

To check the cooling system, the coolant level must be to the correct level with the engine stopped and cold.

After the engine is cool, loosen the pressure cap and let the pressure out of the cooling system. Then remove the pressure cap.

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DO NOT loosen the filler or pressure cap on a hot engine. Steam or hot coolant can cause severe burns.

The level of the coolant should be within 13 mm (1/2 in) below the bottom of the fill pipe or to the proper level on the sight glass, if so equipped.

Test Tools For Cooling System

4C6500 Digital Thermometer Group

The 4C6500 Digital Thermometer Group is used in the diagnosis of over heating (engine hotter than normal) or overcooling (engine cooler than normal) problems. This group can be used to check temperatures in several different parts of the cooling system. The testing procedure is in Special Instruction, NEHS0554.

8T2700 Indicator Group

The 8T2700 Blowby/Air Flow Indicator Group is used to check the air flow through the heat exchanger core. The test procedure is in Special Instruction, SEHS8712.

9U7400 Multitach Group

The 9U7400 Multitach Group is used to check the fan speed. The testing procedure is in Operators Instruction, NEHS0605.

1U7297 or 1U7298 Coolant Tester

Check the coolant solution frequently in cold weather for glycol concentration with the 1U7297 or 1U7298 Coolant Tester to ensure adequate protection. Both testers are used for checking coolant freezing point, and are identical except temperature scale. They give immediate, accurate readings and can be used for antifreeze/coolants that contain ethylene or propylene glycol.

Make Proper Antifreeze Additions

Adding pure antifreeze as a makeup solution for cooling system top-off is an unacceptable practice. It increases the concentration of antifreeze in the cooling system which increases the concentration of dissolved solids and undissolved chemical inhibitors in the cooling system. Add antifreeze mixed with acceptable water to the same freeze protection as your cooling system. Use the chart as follows to assist in determining the concentration of antifreeze to use.

Checking Pressure Cap

One cause for a pressure loss in the cooling system can be a defective seal on the radiator pressure cap.

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DO NOT loosen the filler or pressure cap on a hot engine. Steam or hot coolant can cause severe burns.

After the engine is cool, loosen the pressure cap and let the pressure out of the cooling system. Then remove the pressure cap.

Inspect the pressure cap carefully. Look for damage to the seal or to the surface that seals. Any foreign material or deposits on the cap, seal or surface that seals, must be removed.

Typical Schematic Of Pressure Cap
(A) Sealing surface of cap and expansion tank.

9S8140 Cooling System Pressurizing Pump Group

The 9S8140 Cooling System Pressurizing Pump Group is used to test pressure caps and to pressure check the cooling system for leaks.

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DO NOT loosen the filler or pressure cap on a hot engine. Steam or hot coolant can cause severe burns.

To check the pressure cap for the pressure that makes the pressure cap open, use the procedure that follows:

1. Remove the pressure cap from the expansion tank.

2. Put the pressure cap on the 9S8140 Cooling System Pressurizing Pump Group.

3. Look at the indicator for the exact pressure that makes the pressure cap open.

4. Make a comparison of the reading on the indicator with the correct pressure at which the pressure cap must open.

5. If the pressure cap is defective, install a new pressure cap.

Testing Expansion Tank And Cooling System For Leaks

To test the expansion tank and cooling system for leaks, use the procedure that follows:

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DO NOT loosen the filler or pressure cap on a hot engine. Steam or hot coolant can cause severe burns.

1. Remove the pressure cap from the expansion tank.

2. Make sure the coolant level is full.

3. Put the 9S8140 Cooling System Pressurizing Pump Group on the expansion tank.

4. Get the pressure reading on the indicator to 20 kPa (3 psi) more than the pressure on the pressure cap.

5. Check the expansion tank for outside leakage.

6. Check all connections and hoses for the cooling system for outside leakage.

7. If you do not see any outside leakage and the pressure reading on the indicator is still the same after five minutes, the cooling system does not have leakage. If the reading on the indicator goes down and you do not see any leakage, there is leakage on the inside of the cooling system. Make repairs as necessary.

Water Temperature Indicator Test

Test Location (Typical Example)
(1) Plug.

Check the accuracy of the water temperature indicator if either of the conditions that follow are found:

1. The indicator reads normal, but the engine is too hot and a loss of coolant is found.

2. The indicator shows that the engine is hot, but no loss of coolant can be found.

Remove plug (1) and install the 4C6500 Digital Thermometer Group or the 2F7112 Thermometer. A temperature indicator of known accuracy can also be used to make this check.

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Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

Start the engine and run it until the temperature reaches the desired range according to the test thermometer. If necessary, put a cover over part of the expansion tank or cause a restriction of the air flow. The reading on the indicator for water temperature should agree with test thermometer within the tolerance range of the indicator.

Water Temperature Regulator Test

1. Remove the regulator from the engine.

2. Heat water in a pan until the temperature is 98°C (208°F). Move the water around in the pan to make it all the same temperature.

3. Hang the regulator in the pan of water. The regulator must be below the surface of the water and it must be away from the sides and bottom of the pan.

4. Keep the water at the correct temperature for ten minutes.

5. After ten minutes, remove the regulator and immediately measure the distance the regulator has opened. The distance must be a minimum of 10.4 mm (.41 in).

6. If the distance is less than 10.4 mm (.41 in), make a replacement of the regulator.

Water Pump Pressure Check

Typical Illustration
(1) Plug. (2) Coolant temperature sensor. (3) Water manifold assembly. (4) Water outlet. (5) Temperature regulator housing. (6) Bypass line. (7) Water pump. (8) Plug.

Water pump outlet pressure can be checked on water manifold assembly (3) next to the coolant temperature sensor (2). This check will determine if the water pump is operating correctly.

Remove plug (1) from water manifold assembly (3). Install the pressure indicator (6V7775) in the port and measure the pump pressure. The water pump pressure should be 100 to 125 kPa (15 to 18 psi).

A change in pressure can be measured between plug (1) on the water manifold assembly (4) and plug (8) on the inlet side of water pump (7).

Basic Block

Piston Rings

This engine has a top piston groove and ring of the KEYSTONE (taper) design. The 1U6431 Keystone Piston Ring Groove Gauge Group is available to check the top ring groove in the piston. Use the 8T3149 (#F) Gauge Assembly that is part of this Gauge Group to check the top ring groove on the piston. Refer to the instruction card for correct use of the 1U6431 Gauge Group.

Connecting Rods And Pistons

The 3176C & 3196 Marine Engines use a 129-6675 Cylinder Pack Removal Group with a 1U9897 Bridge, and a 1U6319 Socket to remove a cylinder pack (connecting rod and piston) from the block. Use the 1U9788 Nylon Brush, or the 1U9787 Flex (hone) for reconditioning of the cylinder liners.

Use the 4C3601 Piston Ring Expander to remove or install piston rings.

Use the 1U6684 Piston Ring Compressor to install pistons into cylinder block.

Tighten the connecting rod nuts in the step sequence that follows:

1. Put 2P2506 Thread Lubricant on bolt threads and contact surfaces of nut and cap.

2. Install connecting rod nuts as follows:

Tighten connecting rod nuts to a torque of ... 110 ± 7 N·m (80 ± 5 lb ft)

3. Put a mark on each nut and end of bolt.

4. Tighten each nut an additional 60 ± 5 degrees (1/6turn).

The connecting rod bearings fit tightly in the bore in the rod. If bearing joints or backs are worn (fretted), check bore size. This can be an indication of wear because of a loose fit.

Connecting Rod And Main Bearings

Connecting Rod Bearings

Connecting rod bearings are available with 0.508 mm (.0200 in) and .762 mm (.0300 in) smaller inside diameter than the original size bearings. These bearings are for crankshafts that have been "ground" (made smaller than the original size).

Main Bearings

Main bearings are available with 0.508 mm (.0200 in) and .762 mm (.0300 in) smaller inside diameter than the original size bearings. These bearings are for crankshafts that have been "ground" (made smaller than the original size).

Main bearings are also available with a larger outside diameter than the original size bearings. These bearings are for cylinder blocks that have had the bore for the main bearings "bored" (made larger than the original size). The size available is 0.508 mm (.0200 in) larger outside diameter than the original size bearings.

Cylinder Block

1P3537 Dial Bore Gauge Group

The bore in the block for main bearings can be checked with the main bearing caps installed without bearings. Tighten the nuts that hold the caps to the torque shown in the Specifications. Alignment error in the bores must not be more than 0.08 mm (.003 in). Special Instruction, SMHS7606 gives instructions for the use of 1P4000 Line Boring Tool Group for alignment of the main bearing bores. The 1P3537 Dial Bore Gauge Group can be used to check the size of the bores. Special Instruction, GMG00981 is with the group.

Cylinder Liner Projection

1. Clean the cylinder liner flange and cylinder block surface. Remove any nicks on the top of the cylinder block.

Location of components required to retain the cylinder liner when measuring cylinder liner projection.

2. The illustration and chart identify the components required. An 8T0455 Cylinder Liner Projection Indicator Group is also required.

3. Assemble the components as shown in the illustration. The 7K1977 Washer (4) is made of a cotton fabric that is impregnated with resin. It will not damage the sealing surface of the cylinder block.

NOTE: Inspect washer before measuring liner projection and replace if worn or damaged.

4. Tighten bolts (1) evenly as follows:

a. First tighten each bolt to ... 27 N·m (20 lb ft)

b. Tighten each bolt to ... 54 N·m (40 lb ft)

c. Tighten each bolt to ... 68 N·m (50 lb ft)

d. Tighten each bolt again to ... 68 N·m (50 lb ft)

5. Loosen bolt (5) until dial indicator (6) can be moved. Place gauge body (7) and dial indicator (6) on the long side of gauge.

6. Slide dial indicator (6) down until the point contacts gauge (8) and moves the needle 1/4 revolution clockwise to a vertical position. Tighten bolt (5) and zero indicator.

7. Put gauge body (7) on the cylinder block plate, with the indicator point on the liner flange. Read the dial indicator to find the amount of liner projection. Check projection at four locations (90 degrees apart) around each cylinder liner.

8. If a liner does not meet the liner projection specifications, check the block cylinder bore depth 100.00 ± 0.03 mm (3.937 ± .001 in) and the liner flange 100.12 ± 0.03 mm (3.942 ± 0.001 in) to determine if they are correct. If not within specification, replace and repeat the liner projection measurements.

Flywheel And Flywheel Housing

Face Run Out (Axial Eccentricity) Of The Flywheel Housing

8T5096 Dial Indicator Group Installed (Typical Example)

If any method other than given here is used, always remember bearing clearance must be removed to get correct measurements.

1. Fasten a dial indicator to the flywheel so the anvil of the indicator will touch the face of the flywheel housing.

2. Put a force on the crankshaft toward the rear before the indicator is read at each point.

Checking Face Runout Of The Flywheel Housing

3. With dial indicator set at "0" (zero) at location (A), turn the flywheel and read the indicator at locations (B), (C) and (D).

4. The difference between lower and higher measurements taken at all four points must not be more than 0.38 mm (.015 in), which is the maximum permissible face run out (axial eccentricity) of the flywheel housing.

Bore Runout (Radial Eccentricity) Of The Flywheel Housing

1. Fasten the dial indicator as shown so the anvil of the indicator will touch the bore of the flywheel housing.

2. With the dial indicator in position at (C), adjust the dial indicator to "0" (zero). Push the crankshaft up against the top of the bearing. Write the measurement for bearing clearance on line 1 in column (C) in the Chart For Dial Indicator Measurements.

8T5096 Dial Indicator Group Installed (Typical Example)

NOTE: Write the dial indicator measurements with their positive (+) and negative (-) notation (signs). This notation is necessary for making the calculations in the chart correctly.

3. Divide the measurement from Step 2 by 2. Write this number on line 1 in columns (B) & (D).

4. Turn the flywheel to put the dial indicator at (A). Adjust the dial indicator to "0" (zero).

5. Turn the flywheel counterclockwise to put the dial indicator at (B). Write the measurements in the chart.

Checking Bore Runout Of The Flywheel Housing

6. Turn the flywheel counterclockwise to put the dial indicator at (C). Write the measurement in the chart.

7. Turn the flywheel counterclockwise to put the dial indicator at (D). Write the measurement in the chart.

8. Add lines I & II by columns.

9. Subtract the smaller number from the larger number in line III in columns (B) & (D). The result is the horizontal eccentricity (out of round). Line III, column (C) is the vertical eccentricity.

10. On the graph for total eccentricity, find the point of intersection of the lines for vertical eccentricity and horizontal eccentricity.

11. If the point of intersection is in the range marked "Acceptable", the bore is in alignment. If the point of intersection is in the range marked "Not Acceptable", the flywheel housing must be changed.

Graph For Total Eccentricity
(1) Total Vertical Eccentricity [mm (in)]. (2) Total Horizontal Eccentricity [mm (in)]. (3) Acceptable. (4) Not Acceptable.

Face Runout (Axial Eccentricity) Of The Flywheel

1. Install the dial indicator as shown. Always put a force on the crankshaft in the same direction before the indicator is read so the crankshaft end clearance (movement) is always removed.

Checking Face Runout Of The Flywheel (Typical Example)

2. Set the dial indicator to read "0" (zero).

3. Turn the flywheel and read the indicator every 90 degrees.

4. The difference between the lower and higher measurements taken at all four points must not be more than 0.15 mm (.006 in), which is the maximum permissible face runout (axial eccentricity) of the flywheel.

Bore Runout (Radial Eccentricity) Of The Flywheel

Checking Bore Runout Of The Flywheel (Typical Example)
(1) 7H1945 Holding Rod (2) 7H1645 Holding Rod (3) 7H1942 Indicator (4) 7H1940 Universal Attachment

1. Install the dial indicator (3) and make an adjustment of the universal attachment (4) so it makes contact as shown.

2. Set the dial indicator to read "0" (zero).

3. Turn the flywheel and read the indicator every 90 degrees.

4. The difference between the lower and higher measurements taken at all four points must not be more than 0.15 mm (.006 in), which is the maximum permissible bore runout (radial eccentricity) of the flywheel.

5. Runout (eccentricity) of the bore for the pilot bearing for the flywheel clutch, must not exceed 0.13 mm (.005 in).

Checking Flywheel Clutch Pilot Bearing Bore

Vibration Damper

(1) Viscous vibration damper. (2) Pulley. (3) Crankshaft. (4) Bolts (six).

The viscous vibration damper is installed on the front of crankshaft (3). The vibration damper (1) has a weight in a case. The space between the weight and the case is filled with thick fluid. The weight moves in the case to limit the torsional vibration.

If the viscous vibration damper is leaking, bent or damaged, or if the bolt holes in the viscous vibration damper are loose fitting, replace the damper. Replacement of the damper is also needed at the time of a crankshaft failure due to torsional forces.

NOTE: Bolts (4) must be tightened to a torque of 300 ± 40 N·m (220 ± 30 lb ft)

Electrical System

Test Tools For Electrical System

Most of the tests of the electrical system can be done on the engine. The wiring insulation must be in good condition, the wire and cable connections must be clean and tight, and the battery must be fully charged. If the on-engine test shows a defect in a component, remove the component for more testing.

The service manual Testing & Adjusting Electrical Components, REG00636 has complete specifications and procedures for the components of the starting circuit and the charging circuit.

4C4911 Battery Load Tester

The 4C4911 Battery Load Tester is a portable unit in a metal case for use under field conditions and high temperatures. It can be used to load test all 6, 8 and 12V batteries. This tester has two heavy-duty load cables that can easily be fastened to the battery terminals. A load adjustment knob on the top permits the current being drawn from the battery to be adjusted to a maximum of 1000 amperes. The tester is cooled by an internal fan that is automatically activated when a load is applied.

The tester has a built in LCD digital voltmeter and amperage meter. The digital voltmeter accurately measures the battery voltage at the battery through tracer wires buried inside the load cables. The digital amperage meter accurately displays the current being drawn from the battery under test.

NOTE: Make reference to Operating Manual, SEHS9249 for more complete information for use of the 4C4911 Battery Load Tester.

8T0900 AC/DC Clamp-On Ammeter

The 8T0900 AC/DC Clamp-On Ammeter is a completely portable, self-contained instrument that allows electrical current measurements to be made without breaking the circuit or disturbing the insulation on conductors. A digital display is located on the ammeter for reading current directly in a range from 1 to 1200 amperes. If an optional 6V6014 Cable is connected between this ammeter and one of the digital multimeters, current readings of less than 1 ampere can then be read directly from the display of the multimeter.

A lever is used to open the jaws over the conductor [up to a diameter of 19 mm (.75 in)], and the spring loaded jaws are then closed around the conductor for current measurement. A trigger switch that can be locked in the ON or OFF position is used to turn on the ammeter. When the turn-on trigger is released, the last current reading is held on the display for five seconds. This allows accurate measurements to be taken in limited access areas where the digital display is not visible to the operator. A zero control is provided for DC operation, and power for the ammeter is supplied by batteries located inside the handle.

NOTE: Make reference to Special Instruction, SEHS8420 for more complete information for use of the 8T0900 Clamp-On Ammeter.

6V7070 Heavy-Duty Digital Multimeter

The 6V7070 Heavy-Duty Digital Multimeter is a completely portable, hand held instrument with a digital display. This multimeter is built with extra protection against damage in field applications, and is equipped with seven functions and 29 ranges. The 6V7070 Multimeter has an instant ohms indicator that permits continuity checking for fast circuit inspection. It also can be used for troubleshooting small value capacitors.

NOTE: Make reference to Special Instruction, SEHS7734 for complete information for use of the 6V7070 Multimeter.

Battery

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Never disconnect any charging unit circuit or battery circuit cable from the battery when the charging unit is operated. A spark can cause an explosion from the flammable vapor mixture of hydrogen and oxygen that is released from the electrolyte through the battery outlets. Injury to personnel can be the result.

The battery circuit is an electrical load on the charging unit. The load is variable because of the condition of the charge in the battery. Damage to the charging unit will result if the connections (either positive or negative) between the battery and charging unit are broken while the charging unit is in operation. This is because the battery load is lost and there is an increase in charging voltage. High voltage will damage, not only the charging unit, but also the regulator and other electrical components.

Use the 4C4911 Battery Load Tester to load test a battery that does not hold a charge when in use. Refer to Operating Manual, SEHS9249 for more detailed instructions on use of the 4C4911 Battery Load Tester. See Special Instruction, SEHS7633, Battery Test Procedure, for the correct procedure and specifications to use when testing batteries.

Charging System

The condition of charge in the battery at each regular inspection will show if the charging system operates correctly. An adjustment is necessary when the battery is constantly in a low condition of charge or a large amount of water is needed (more than one ounce of water per cell per week or per every 100 service hours).

When it is possible, make a test of the charging unit and voltage regulator on the engine, and use wiring and components that are a permanent part of the system. Off-engine (bench) testing will give a test of the charging unit and voltage regulator operation. This testing will give an indication of needed repair. After repairs are made, again make a test to give proof that the units are repaired to their original condition of operation.

To check for correct output of the alternator, see the Specifications module.

For complete service information, refer to Service Manual Module, SENR3862. This module is part of REG00636 Service Manual.

Before the start of on-engine testing, the charging system and battery must be checked as shown in the Steps that follow:

1. Battery must be at least 75 percent (1.225 Sp.Gr.) fully charged and held tightly in place. The Battery holder must not put too much stress on the battery.

2. Cables between the battery, starting motor and engine ground must be the correct size. Wires and cables must be free of corrosion and have cable support clamps to prevent stress on battery connections (terminals).

3. Leads, junctions, switches, and panel instruments that have direct relation to the charging circuit must give correct circuit control.

4. Inspect the drive components for the charging unit to be sure they are free of grease and oil and have the ability to operate the charging unit.

Alternator Regulator Adjustment

When an alternator is charging the battery too much or not enough, the charging rate of the alternator should be checked. Make reference to the Specifications module to find all testing specifications for the alternators and regulators.

Alternator
(1) Ground terminal. (2) Pulley nut.

No adjustment can be made to change the rate of charge on the alternator regulators. If rate of charge is not correct, a replacement of the regulator is necessary.

Alternator Pulley Nut Tightening

Tools To Tighten Alternator Pulley Nut
(1) 8T9293 Torque Wrench. (2) 8S1588 Adapter (1/2 inch female to 3/8 inch male). (3) 2P8267 Socket Assembly. (4) 8H8517 Combination Wrench (11/8 inch). (5) 8T5314 Socket.

Tighten the nut that holds the pulley to the specifications given in the Specification Module.

Starting System

Use the multimeter in the DCV range to find starting system components which do not function.

Move the start control switch to activate the starter solenoid. Starter solenoid operation can be heard as the pinion of the starting motor is engaged with the ring gear on the engine flywheel.

If the solenoid for the starting motor will not operate, it is possible that the current from the battery did not get to the solenoid. Fasten one lead of the multimeter to the connection (terminal) for the battery cable on the solenoid. Put the other lead to a good ground. A zero reading is an indication that there is a broken circuit from the battery. More testing is necessary when there is a voltage reading on the multimeter.

The solenoid operation also closes the electric circuit to the motor. Connect one lead of the multimeter to the solenoid connection (terminal) that is fastened to the motor. Put the other lead to a good ground. Activate the starter solenoid and look at the multimeter. A reading of battery voltage shows the problem is in the motor. The motor must be removed for further testing. A zero reading on the multimeter shows that the solenoid contacts do not close. This is an indication of the need for repair to the solenoid or an adjustment to be made to the starter pinion clearance.

Make a test with one multimeter lead fastened to the connection (terminal) for the small wire at the solenoid and the other lead to the ground. Look at the multimeter and activate the starter solenoid. A voltage reading shows that the problem is in the solenoid. A zero reading is an indication that the problem is in the start switch or the wires for the start switch.

Fasten one multimeter lead to the start switch at the connection (terminal) for the wire from the battery. Fasten the other lead to a good ground. A zero reading indicates a broken circuit from the battery. Make a check of the circuit breaker and wiring. If there is a voltage reading, the problem is in the start switch or in the wires for the start switch.

A starting motor that operates too slow can have an overload because of too much friction in the engine being started. Slow operation of the starting motor can also be caused by a short circuit, loose connections and/or dirt in the motor.

To check for correct output of starting motors and starter solenoid, see the Specifications module.

For complete service information, refer to Service Manual Module, SENR3581. This module is part of REG00636 Service Manual.

Pinion Clearance Adjustment

When the solenoid is installed, make an adjustment of the pinion clearance. The adjustment can be made with the starting motor removed.

Typical Connection for Checking Pinion Clearance
(1) Connector (from MOTOR terminal on solenoid to motor). (2) SW terminal (3) Ground terminal.

1. With the solenoid installed on the starting motor, remove connector (1).

2. Connect a battery, of the same voltage as the solenoid, to the terminal (2), marked SW.

3. Connect the other side of the battery to ground terminal (3).

4. Connect for a moment a wire from the solenoid connection (terminal) marked Motor to the ground connection (terminal). The pinion will shift to crank position and will stay there until the battery is disconnected.

Typical Pinion Clearance Adjustment
(4) Shaft nut. (5) Pinion. (6) Pinion clearance.

5. Push the pinion toward the commutator end to remove free movement.

6. Pinion clearance (6) must be 8.3 to 9.9 mm (.33 to .39 in).

7. To adjust pinion clearance, remove plug and turn shaft nut (4).

8. After the adjustment is completed, install the plug over adjustment shaft nut (4) and install connector (1) between the MOTOR terminal on the solenoid and the starting motor.

Air Starting System

Pressure Regulating Valve

Pressure Regulating Valve (Typical Illustration)
(1) Adjustment screw. (2) Regulator inlet. (3) Regulator outlet.

To check and adjust the pressure regulating valve, use the procedure that follows:

1. Drain the line to the pressure regulating valve or drain the air storage tank.

2. Disconnect the regulator from the starter control valve.

3. Connect an 8T0849 Pressure Indicator to regulator outlet (3).

4. Put air pressure in the line or tank.

5. Check the pressure.

6. Adjust the pressure regulating valve to ... 690 to 1030 kPa (100 to 150 psi)

7. Remove the air pressure from the line or tank.

8. Remove the 8T0849 Pressure Indicator and connect the air pressure regulator to the line to the air starting motor.

Each engine application will have to be inspected to get the most acceptable starting results. Some of the factors that affect regulating valve pressure setting are: attachment loads pulled by engine during starting, ambient temperature conditions, oil viscosity, capacity of air reservoir, and condition of engine (new or worn).

The advantage of setting the valve at the higher pressures is increased torque for starting motor and faster rotation of engine. The advantage of setting the valve at the lower pressures is longer time of engine rotation for a given capacity of supply air.

Lubrication

Always use an air line lubricator with the air starting motor. Diesel fuel is used to lubricate the air starting motor.

Air Starting Motor

Components Of The Air Starting Motor
(1) Motor housing cover. (2) Plug. (3) Plug. (3A) Plug. (6) Bolt (cap screw). (7) Lockwasher. (8) Gasket. (9) Rotor rear bearing. (10) Bearing retainer. (11) Rear end plate. (12) Cylinder. (13) Dowel. (14) Rotor vane. (15) Rotor. (16) Front end plate. (17) Rotor front bearing. (18) Motor housing. (19) Gear case gasket. (20) Rotor pinion. (21) Rotor pinion retainer. (22) Gear case. (23) Bearing rejecting washer. (24) Rear bearing (for the drive shaft). (25) Drive gear. (25A) Thrust washer. (26) Key (for the drive gear). (27) Front bearing (for the drive shaft). (28) Gear case cover. (29) Grease seal (for the drive shaft). (30) Cover seal. (31) Piston seal. (32) Bolt. (33) Lockwasher. (34) Drive shaft. (35) Drive shaft collar. (36) Piston. (36A) Piston ring. (37) Shift ring. (38) Shift ring retainer. (39) Shift ring spacer. (40) Piston return spring. (41) Return spring seat. (42) Starter drive (pinion). (43) Lockwasher. (44) Bushing (for the bolts). (45) Drive housing. (46) Drive housing bushing. (47) Oiler felt (for the bushing). (48) Oiler plug.

Rear View Of The Cylinder And Rotor For Clockwise Rotation
(12) Cylinder. (12A) Air inlet passages. (12B) Dowel hole. (15) Rotor.

Air Starting Motor
(6) Bolt. (12) Cylinder. (15) Rotor. (16) Front end plate. (22) Gear case. (25) Drive gear. (28) Gear case cover. (29) Grease seal. (32) Bolt. (34) Drive shaft. (35) Drive shaft collar. (42) Starter drive (pinion). (45) Drive housing. (49) Air inlet. (50) Deflector (air outlet). (51) Mounting flange (on the drive housing).

Cylinder (12) must be assembled over rotor (15) and on front end plate (16) so dowel hole (12B) and inlet passages (12A) for the air are as shown in the rear view illustration of the cylinder and rotor. If the installation is not correct, starter drive (42) will turn in the wrong direction.

Tighten the bolts (6) of the rear cover in small increases of torque for all bolts until all bolts are tight 30 ± 5 N·m (22 ± 4 lb ft).

Put a thin layer of lubricant on the lip of seal (29) and on the outside of drive shaft collar (35), for installation of drive shaft (34). After installation of the shaft through gear case cover (28) check the lip of grease seal (29). It must be turned correctly toward drive gear (25). If the shaft turned the seal lip in the wrong direction, remove the shaft and install again. Use a tool with a thin point to turn the seal lip in the correct direction.

Tighten bolts (32) of the drive housing in small increases of torque for all bolts until all bolts are tight 11.3 N·m (100 lb in).

Check the motor for correct operation. Connect an air hose to motor air inlet (49) and make the motor turn slowly. Look at starter drive (42) from the front of drive housing (45). The pinion must turn clockwise.

Connect an air hose to the small hole with threads in drive housing (45), nearer gear case (22). When a little air pressure goes to the drive housing, starter drive (42) must move forward to the engaged position. Also, the air must get out through the other hole with threads nearer mounting flange (51).

Instruments And Indicators

Magnetic Pickup

Typical Illustration

(1) Clearance between end of magnetic pickup and gear ... 0.10 to 0.75 mm (.004 to .030 in)

NOTE: This distance is set by turning magnetic pickup into threads until magnet is against the gear tooth while the engine is stopped. Now back magnetic pickup out 1/3 turn ± 18 degrees and tighten nut (2) as follows.

(2) Nut. Tighten nut to a torque of ... 45 ± 7 N·m (33 ± 5 lb ft)

Electric Indicators

1. Put the indicator in position with the letters horizontal and the face 30 degrees back from vertical.

Wiring Diagram For Test
(1) Terminal (for test voltage). (2) Test resistance.

2. Connect the indicator in series with the power source and the middle test resistance shown in the chart.

3. Let the indicator heat at the middle resistance for five minutes, then check the pointer position for all of the resistance given.

Mechanical Indicators For Temperature

Direct Reading Indicator

To check these indicators, put the bulb of the indicator in a pan of oil. Do not let the bulb touch the pan. Put a thermometer in the oil to measure the temperature. Make a comparison of temperatures on the thermometer with the temperatures on the direct reading indicator.

Mechanical Indicators For Pressure

Direct Reading Indicator

To check these indicators connect the indicator to a pressure source that can be measured with accuracy. Make a comparison of pressure on the indicator of test equipment with the pressures on the direct reading indicator.