Usage:
Introduction
The purpose of this instruction is to aid in the proper use of the 4C3502 Engine Repair Indicator Kit designed for dealer Product Support Sales Representatives (PSSR).
The kit enables a few simple tests to be made which will assist the PSSR in evaluating a machine's condition and in many cases determine if a before failure overhaul is recommended for the engine. When a determination cannot be made from the following procedure the dealers Service Department should be consulted for further machine evaluation.
The tests described in this instruction are not intended to be a substitute for any type of inspection which might be performed by a qualified Caterpillar service mechanic.
Before making a call on a customer, inspect each item in the kit to ensure it is included and in good working order. The test should be first performed on a machine in the dealership to become more familiar with the tooling.
PEEP8211 Engine Evaluation Worksheet
The Engine Evaluation Worksheet, form PEEP8211, included with the kit should be used to record the data obtained from the test. The worksheet aids in the completion of the machine condition evaluation and determination for a before failure overhaul.
This instruction covers each separate section of the evaluation worksheet and the use of tooling, tests and procedures for each section.
Necessary Parts
The following chart lists the items in each 4C3502 Engine Repair Indicator Kit. Replacement parts/forms can be ordered from the Parts Department except for the items with alternate sources indicated.
| NOTICE |
|---|
The kit contains only a sampling of Lubrication and Maintenance Interval Decals. A complete listing of available decals is published quarterly in the Service Magazine. |
Customer And Machine Information
It is essential that this section of the worksheet be completed in full for proper documentation of the inspection. This information will allow you to begin a history file, by machine, that may be referenced later. It also contains key information to assist your Service Department should they be required to further inspect the machine or conduct repairs.
Machine Working Conditions
The questions in this section are related to the machine application and its operating environment. These questions are required for the Engine Overhaul Estimator Guide calculations.
The question regarding load factor assigns a rating to the amount of time the engine is fully loaded and therefore burning a maximum amount of fuel. The following descriptions will assist in rating the particular machine application being evaluated.
| NOTICE |
|---|
The load factor descriptions may also be found in the Performance Handbook and on the Overhaul Estimator. |
Track-Type Tractors
High: Steady ripping, shuttle pushloading, agricultural drawbar work at full throttle, little or no idle or travel in reverse.
Medium: Production dozing, pulling scrapers, most pushloading.
Low: Considerable idle or travel with no load.
Motor Graders
High: Ditching, fill spreading, spreading base material, ripping, heavy road maintenance, snow plowing.
Medium: Average road maintenance, road mix work, scarifying, snow plowing.
Low: Finish grading, light maintenance, road travel.
Skidders
High: Skidding large loads [6810 kg (15000 lb) for the 518; 11350 kg (25000 lb) for the 528] in steep terrain (over 10%) with high skidding resistance.
Medium: Skidding medium size loads [4540-6810 kg (10000-15000 lb) for the 518; 6810-11350 kg (15,000-25,000 lb for the 528] in moderate terrains (5-10%) with average skidding resistance.
Low: Skidding small loads in flat terrain with low skidding resistance.
Feller Bunchers, Delimbers And Loaders
High: Steady felling and bunching with little idle time.
Medium: Steady cycling with frequent periods of idle.
Low: Light easy work. Considerable idling.
Backhoe Loaders
High: Production work with long cycles and/or constant flow implements.
Medium: General work with regular cycles in medium applications.
Low: Utility work with intermittent cycles in light to medium applications.
Pipelayers
High: Steady cycling, little or no idle time.
Medium: Normal cycling, less than 50% idle time.
Low: Light duty utility with 50% or more idle time.
Wheel Tractor-Scrapers
High: Continuous high total resistance conditions with steady cycling.
Medium: Typical road building use.
Low: Average use but with considerable idling, favorable grades, low rolling resistance and easy loading material.
Off-Highway Trucks And Tractors
High: Long haul times with frequent unfavorable grades. Steady cycling with little or no idle time. Haul roads are poorly maintained with high rolling resistance.
Medium: Normal load and hull times. Some adverse grades. Varying load and haul road resistance.
Low: Considerable idle time. Short to medium hauls on well maintained roads. Minimum total resistance.
Articulated Dump Trucks
High: Long haul times with frequent unfavorable grades. Steady cycling with little or no idle time. Haul roads are poorly maintained with high rolling resistance.
Medium: Normal load and haul times. Some adverse grades. Varying load and haul road resistance.
Low: Considerable idle time. Short to medium hauls on well maintained roads. Minimum total resistance.
Wheel Tractors And Compactors
High: Heavy dozing, compacting heavy material.
Medium: Production dozing, most pushloading, shovel cleanup, normal compaction.
Low: Considerable idle or travel with no load.
Wheel Loaders
High: Steady cycling on the basic loader cycle.
Medium: Steady cycling but over haul distances or work on basic loader cycle with frequent periods of idle.
Low: Light utility work. Considerable idle.
Track-Type Loaders
High: Continuous loading from bank on basic loader cycle.
Medium: Bank loading on basic loader cycle with idle periods or stockpile work including travel.
Low: Large amounts of idle in any application.
Hydraulic Excavators
High: Most pipeline applications in hard, rocky material. Digging 90-95% of the daily work schedule.
Medium: Most residential sewer applications in natural bed clay. Digging 60-85% of the daily work schedule. Most log loading applications.
Low: Most utility, urban applications in sandy loam. Digging less than 50% of the daily work schedule. Scrap handling applications.
Front Shovels
High: Steady cycling in hard to dig material.
Medium: Steady cycling with frequent periods of idle.
Low: Light easy work, considerable idle.
Visual Engine Inspection
Walk around the machine and inspect those items listed on the worksheet. Any problems found should be noted on the worksheet, brought to the attention of the customer and either corrected by him or your Service Department.
| NOTICE |
|---|
Most of the following items are inspected with the machine shut off and cooled down. If the radiator cap is too hot to hold, the machine is not sufficiently cooled down. Do not attempt to check coolant levels, hoses, etc. with a hot engine. Smoke should be observed during normal operation before the machine is shutdown or while completing the Engine Evaluation portion of the worksheet. |
Hoses
 |
Do not attempt to tighten hose connections when the coolant is hot. The hose may come off causing serious burns. |
 |
Check hoses for flexibility, cracks and any bulges which would indicate weakened areas. Also look for leaks at the connections.
Vee Belts
Check vee belts for any signs of unusual wear or slippage. Check to see how much the belt extends out of the pulley groove. If the belt sits below the pulley edge either the belts or the pulley groove are excessively worn. Cracks found on the underside of the belts indicate they have fatigued and should be replaced.
Battery
Open the lid to the battery compartment and check for signs of corrosion or leaks. The hold down straps should be in place and tight to restrict battery movement preventing internal and external damage. Battery cables should be tight and covered with battery grease to resist corrosion. Any large amount of dirt or debris should be removed.
If the battery is serviceable (conventional or low maintenance), check the water levels of each cell. The levels must be up to the neck in each cell prior to performing the specific gravity test. If water is added, the battery must be recharged prior to the specific gravity test.
Use the battery tester provided in the kit to test each cell before adding water. Cells showing a low charge indicate either a battery or charging system problem which should be noted and corrected by either the customer or your Service Department.
Engine Oil
Check the engine oil to determine if it is at the proper level. Observe any leaks which appear to be engine oil. Fuel dilution of the oil can sometimes be detected by placing a drop of oil on a paper shop towel. As the oil is absorbed into the cloth it will form a dark circle. If fuel is present it will form a lighter ring or "halo" around the outside of the darker circle formed by the oil. The greater the amount of fuel, the larger the lighter colored ring will be. Make note of the type of oil filters currently on the engine.
During the operator interview, determine what brand and viscosity of oil is being used and the oil change intervals. The oil change labels provided in the kit may be applied to the machine to allow the customer's maintenance department to record each time the machine is serviced.
Air System
Check all air inlet piping and connections to the turbocharger (if equipped) for any signs of loose connections. Leaks allowing unfiltered air to enter the engine will greatly increase engine wear rates.
The air filter service indicator should be located on the air filter housing (downstream) or inlet piping between the housing and the air inlet manifold or turbocharger. It continually measures the restriction of the air filter by measuring the vacuum between the engine and the filter.
The latest version of the 8N2694 Service Indicator is designed to lock up at the highest point of restriction under full load so it can be read later after the machine has been shut down. After the reading is taken the indicator may be reset by depressing the button on the end of the indicator. Check the indicator and record the amount of restriction. The filter should be serviced when its plunger reads in the danger zone (30 inches of water).
The indicator should be visually inspected regularly to ensure it is operating correctly. The plunger will fluctuate slightly during machine operation indicating it is functioning properly. If in doubt, remove the indicator and attach it to one of the small hoses on the small vacuum gun included in the kit. Pull back the plunger to simulate a restriction, and compare the reading on the machine's indicator to the new indicator attached to the other tube. If the readings are not the same the old indicator should be replaced.
If the machine does not have a service indicator discuss the benefits of such a device with the machine owner.
The indicator and suction gun provided in the kit can be used for your demonstration. For more information, refer to Tool Announcement PEHP9013 Facts About Air Filter Restriction and Proper Air Filter Maintenance located in the literature compartment of your kit.
Gauges
At any time during the inspection, while the machine is running, check the operators station to see if all the gauges (including the EMS panel) are functional.
Cooling System Evaluation
Radiator
Check the radiator for any external debris plugging. Air restriction can significantly reduce the cooling efficiency of the machine.
Remove the radiator cap (with cool engine only) and check the condition of the seal. Visually check for signs of corrosion or dirty coolant. Oil in the coolant will cause a milky appearance.
Also look for any signs of radiator leaks such as wet or extremely dirty areas. Check the water pump weep hole for signs of excessive oil or coolant leakage, which would be an indication of worn bearings or seals.
Ask the operator or maintenance personnel if coolant is being added on a regular basis. Excessive coolant loss through the radiator relief valve could be an indication of combustion gas entering the coolant.
If this is the first inspection of this machine, temperature recorders are included in the kit and should be applied to the top and bottom radiator tanks or on the water inlet and outlet piping, at the radiator, to record maximum operating temperatures.
Initially, apply the 8T2821 Recorder [82-110°C (180-230°F)] to the bottom tank and both the 8T2821 and 8T2822 Recorders [104-132°C (220-270°F)] to the top tank at a location below the normal coolant level. Be sure to apply them to a clean, dry surface, free of corrosion. You may use the scraper in the kit to clean an area to ensure good adherence.
The labels can be read during a later visit or after the machine has been put back to work. If the labels indicate the radiator temperatures have reached or exceeded 110°C (230°F) the machine is operating too hot and should be investigated. The additional range of the 8T2822 recorder on the top tank should allow you to determine the actual maximum temperature.
The bottom tank temperature should read approximately 6-8°C (10-15°F) less than the top tank. If the bottom tank temperature is more than 8°C (15°F) less than the top tank then there may be a flow problem through the radiator. If the top and bottom tanks have very little temperature differential but are both high there may be external plugging and/or low air flow through the radiator.
| NOTICE |
|---|
Not all overheating problems are caused by the engine and/or radiator. Other heat sources such as the transmission or hydraulic systems can overload the engine cooling system as well. |
Any problems with overheating must be corrected immediately by either the customer or your Service Department. Overheating accounts for more engine failures than any other problem today. After the problem has been corrected, new labels must be placed on the radiator to continue to monitor the system.
Coolant tests
Coolant testing should only be done on a cold engine. Remove the cap slowly to release any cooling system pressure. Check the coolant for signs of oil. A milky appearance or a black scum on the top of the coolant may indicate a leaking engine oil cooler.
Follow the instructions with the coolant test kit to check both the concentration of glycol as well as the amount of conditioner. The coolant should contain approximately 30-60% glycol with 3-6% conditioner.
Refer to SEBD0518, entitled, Know Your Cooling System for a better understanding of the importance of proper cooling system maintenance. Also refer to Tool Announcement NEHG3012, entitled, New 8T5296 Conditioner Test Kit. Both are located in the literature compartment of your kit.
Engine Evaluation
Excessive Smoke
When possible, observe the machine during normal operation for sign of excessive smoke. Some smoke during startup and acceleration will be normal. Continuous smoke during operation however may indicate a problem.
In general, black smoke is caused by partially burned fuel which indicates over fueling or an air restriction problem (plugged air filter element). This could possibly be corrected with a tune-up.
Blue smoke is caused by oil consumption which may be due to ring and liner wear, valve guide wear or more minor problems such as leaking turbocharger seals or plugged crankcase ventilation.
White smoke can be steam due to moisture in the combustion chamber or unburned fuel due to a possible fuel system problem. Again some white smoke at startup may be normal, especially under cold ambient conditions until the machine reaches operating temperature.
Filter Inspection
The 6V7905 Filter Cutter, the 2P8250 Strap Wrench Assembly and the 1U7113 Ratchet (1/2" drive) allows for the internal inspection of a used filter to determine if debris is present.
Use the utility knife included in the kit to cut the internal paper type filter open. Any signs of large chunks of material, especially metallic material, indicates an immediate problem which should be checked by the Service Department.
Fine non-metallic materials, such as paint chips, gasket or paper fibers, and other non-metallic items, may be present in smaller quantities and can be identified by color or by their magnetic properties. Use the magnet included in the kit to determine how much of the material is ferrous (iron) which would normally be an indication of a problem requiring attention.
Aluminum particles (dull gray and not magnetic) are generated by piston wear or bearing wear. This inspection is normally best performed in front of the customer to illustrate the condition of the engine. Accumulations of more than a few particles, may be an indication requiring attention and investigation by the customer or the Service Department.
Crankcase Pressure (Blowby) Measurement
The pressure gauge and tubing provides a simple means to measure crankcase pressure. Excessive pressure is often an indication of piston ring and liner wear. As with all indicators however the measurement alone cannot identify the need for a complete overhaul.
Excessive pressure can also be caused by worn valve guides, a damaged fuel ratio diaphragm, a damaged turbocharger seal or a restriction in the crankcase ventilation system. If no other indicators are present, these areas should be investigated.
To use the pressure gauge, attach the flexible hose to the high pressure port of the gauge with the other end placed over the engine dipstick tube. If the hose does not fit tightly over the tube use a small hose clamp to ensure a pressure tight fit.
The kit is equipped with approximately 3 m (10 ft) of hose. This is to allow the person conducting the test to be back away from the machine when it is operating. Be sure the hose is not kinked or restricted in any way.
The operator can now start the engine. After the engine has reached operating temperature the machine should be placed in torque convertor stall. This is done with the engine at high idle, a forward gear selected and the brakes applied to prevent the machine from moving. If the brakes cannot hold the machine, select a higher gear.
| NOTICE |
|---|
This procedure is only to be used with machines that have torque convertor drives. Do not attempt it on direct drive machines such as SA track type tractors or motor graders. For direct drive machines, this test must be made with the machine loaded under operating conditions or partially loaded with the hydraulics stalled (against relief pressure). |
|
Make sure all personnel that are not approved are kept off the machine and in view of the operator. |
|
The person taking the reading should always be clear of the machine and in full view of the operator. Read the gauge with the machine at torque convertor stall and record the reading. Compare the readings to the following chart.
Scheduled Oil Sampling
If the customer is currently on a Scheduled Oil Sampling (S·O·S) program you should review the records to see if a problem has been indicated. Each report from your lab will include recommendations and address any problem areas.
If the customer is not on S·O·S, explain the benefits of the program in monitoring his machine and preventing unscheduled downtime. The S·O·S report is an important factor in determining the need for engine repairs. Refer to PEDP7105, entitled Scheduled Oil Sampling included in the kit for assistance in discussing S·O·S with your customer.
Although only one sample does not provide a clear picture of the engine's condition, encourage the customer to take a sample, especially if a problem is suspected. This will hopefully result in a regular enrollment for the machine.
Operator Interview
The operator interview is essential to properly evaluate the machine's condition. Indicators such as lack of power, unusual noise and hard starting are all signals that problems are occurring within the engine.
If fuel consumption records are maintained, an increase in fuel consumption in the same application is an indication of a problem.
Oil consumption is a very good indicator of ring and liner wear. As a rule of thumb, if the amount of make-up oil has doubled since the machine was new the engine is approaching the need for either a overhaul or component repair. If the consumption has tripled the problem should be addressed in the near future.
Estimated Hours
By using the information collected in the Machine Working Conditions section of the worksheet the Overhaul Estimator can be used to calculate an estimated overhaul hour range for the machine. This range can be described as a "repair window" based on the machine model and application information inputted.
This repair window represents an overhaul range based on ring and liner wear or a loss of oil control only. It does not consider any type of sudden fatigue failures which might occur. As noted on the calculator, this range is merely an estimate and must be used only in conjunction with the other indicators described in this instruction.
Utilizing the Overhaul Estimator Guide, demonstrate to the customer the positive impact on operating costs by improving preventive maintenance.
Recommendations
The recommendations should include any minor problems found during the engine evaluation. Depending on the severity of the problem the customer may be able to correct the problem himself.
If a need for an overhaul is suspected, add up the problem indicators to determine how many indicate possible excessive engine wear. Look at the current hours on the machine and compare to the estimated hours provided by the calculator. If six or more indicators show a problem and the machine is within the hour range an overhaul is probably recommended.
If the machine is significantly below the hour range but has several severe indicators, your Service Department should be called to further evaluate the machine. In some cases a component repair such as a turbocharger may be all that is required.
Use the information obtained from the engine evaluation to open a dialogue with the customer to discuss your dealers engine maintenance and repair option program.