Installation of Engine Timing Control on 3512 Spark Ignited Turbocharged and Aftercooled Engines{1000} Caterpillar

Introduction

Information for installation of an engine timing control on the above engines is given in this instruction. To install the new timing control, certain original equipment parts must be removed, according to engine model and serial number. It will then be necessary to install new parts on the engine.

Removal and installation information for these parts is given in this instruction.

If an engine is equipped with a Fairbanks Morse ignition system, it will be necessary to remove the complete ignition system, perform some modification to the flywheel housing, then install the new parts necessary to adapt the engine timing control.

For those engines that are equipped with an altronic magneto, make sure the magneto has the variable timing feature. (An additional connector is needed on the magneto rear face for connection of the timing control unit.)

NOTE: It is necessary to have a 24 Volt power source available at all times, for operation of the timing control.

Reference: Service Manual, Parts Book.

Modification of Flywheel Housing Equipped with Core Plug

To install this timing control system on this engine, it will be necessary to install a magnetic pickup to be used as a crankshaft angle sensor.

* Some engines will have a flywheel housing that already has a threaded hole, with a plug in it, that can be used for installation of the magnetic pickup. The modification procedure given here will not be necessary for those engines. It will be necessary, however, to remove the plug and install the magnetic pickup as described later in this instruction.

* For those engines that are equipped with a core plug [refer to core plug (1) in the illustration that follows] it will be necessary to do the complete flywheel housing modification procedure given here.

NOTE: In this procedure, a new plug will be needed for installation in the flywheel housing. A special template is needed to accurately identify the location to drill and tap two holes in this new plug. Accurate location of both of these holes is necessary. One hole is used for installation of a bolt to retain the newly installed plug and keep it from turning. The second hole will be used for installation of the crankshaft angle sensor.

The new plug and the template, used for this modification procedure only, can be obtained by contacting Engine Division Service Engineering, Caterpillar Inc. It will be necessary to return the template to Service Engineering after your modification is completed.

1. Remove core plug (1) from hole (A) in the right front face of the flywheel housing. Install the new plug in hole (A).

2. Remove cover plates (3) and (4).

NOTE: Removal of cover plate (4) is necessary to observe inside the flywheel housing during the following procedure.

3. Put template (6) in position on the flywheel housing, over new plug (5) [installed in hole (A) in Step 1]. The template has a hole that permits it to fit over plug (2) and its mounting boss.

4. Align the two bolt holes [locations (C) and (D)] in the template, with the two bolt holes that were used to fasten cover plate (3) to the flywheel housing.

Use one 0S1608 Bolt with a 5M2894 Washer at location (C) and one 0S1591 Bolt with a 5M2894 Washer at location (D), to fasten the template in position on the flywheel housing.

NOTE: In the procedure that follows, holes will be drilled in the plug that was installed in the flywheel housing in Step 1. It will also be necessary to cut threads in the drilled holes. Do not permit metal chips to fall inside the flywheel housing during this procedure.

5. Drill a 5.20 mm (0.20")Ø hole at location (E) through the plug and into the flywheel housing.

Remove the drill bit from the drill chuck. Turn the drill bit around and put the blunt end in the hole just drilled to hold the plug in position.

6. Drill a 14.50 mm (.570")Ø hole at location (B).

7. Remove the template from the flywheel housing.

NOTE: Make sure to remove all metal chips from both inside and outside the flywheel housing.

8. Use a 1P3021 Tap to cut 1/4"-20 threads in hole (E).

Install a 0S1615 Bolt with a 5P0537 Washer in hole (E) to secure the plug to the flywheel housing.

9. Use a 1P3034 Tap to cut 5/8"-18 threads in hole (B).

NOTE: Make sure to remove all metal chips from both inside and outside the flywheel housing.

Installation of 9Y4842 Cover and Control Group on 3512 Engines

The parts needed are given in the following parts list.

The illustrations give the location for the installation of the two 9Y3904 Covers that are needed. Before installation of the new covers, remove the corresponding original covers and their gaskets.

Make sure all of the original O-ring seal is removed and the sealing surface of the cylinder block is completely clean. This will ensure a good seal with the new O-ring seal.

Camshaft Cover Installation Location (Left Side): A. Installation location for a 9Y3904 Cover (1) on a 3512 Engine. B. Rear face of the cylinder block.

Camshaft cover Installation Location (Right Side): B. Rear face of cylinder block. C. Installation location for a 9Y3904 Cover (1) on a 3512 Engine.

F. Tighten to a torque of 10 ± 2 N·m (90 ± 18 lb in). H. Flywheel housing. K. Cylinder block.

1. Adjust sensor (magnetic pickup) (4) at location (G) (on top of flywheel housing) as follows:

* With the engine stopped, thread magnetic pickup into the hole until the magnet core is against the teeth of the flywheel gear, then turn it back out 1/2 ± 1/10turn

* Tighten the locknut to a torque of 13 ± 1.0 N·m (125 ± 9 lb in). Clearance between the end of the magnetic pickup and the flywheel gear teeth should be 0.56-0.84 mm (0.02-0.03").

2. Adjust sensor (magnetic pickup) (4) at location (J) (in the front face of the flywheel housing) as follows:

* With the engine stopped, thread magnetic pickup into the hole (in the front face of the flywheel housing) until the magnet core is against the front face of the flywheel, then turn it back out 1/2 ± 1/10 turn

* Tighten the locknut to a torque of 13 ± 1.0 N·m (125 ± 9 lb in). Clearance between the end of the magnetic pickup and the front face of the flywheel should be 0.56-0.84 mm (0.02-0.03").

3512 Spark Ignited Generator Set Engine

These engines can have any one of three ignition systems. Parts replacement will, therefore, depend upon what ignition system a specific engine may have. Refer to the topic headings with your specific engine serial number to determine parts replacement requirements.

3512 Spark Ignited Generator Set Engine (4KC90, 91 and 92)

If the engine is equipped with a 1W8466 Ignition System (Fairbanks Morse Fixed Timing Ignition System), all parts in the ignition system will require replacement. Refer to the chart that follows for ignition system parts needed to install on the engine.

Before the new magneto can be installed correctly, it may be necessary to index drive coupling (A) to the correct angle (B). Refer to the engine Service Manual for procedure and specifications on angle (B).

3512 Spark Ignited Generator Set Engine (4KC93 and 94)

These engines have the 7C1144 Altronic Variable Timing System. For these engines only minimal parts replacement will be necessary.

It will be necessary, however, to inspect each 7W4377 Ignition Coil (1) on the engine to make sure they are all of the latest type. The latest type 7W4377 Ignition Coil has a raised portion, location (A), at the base of the coil.

If the engine does not have the latest type 7W4377 Ignition Coils as described here, replace all ignition coils on the engine with the newer type coils.

The parts given in the following parts list will be needed to modify the ignition system so it is similar to current production engines.

3512 Spark Ignited Generator Set Engine (4KC96-118)

These engines have the 7C0481 Altronic Ignition System (Fixed Timing) and only minimum parts replacement will be necessary to install the engine timing control.

Remove plug assembly (1) from magneto (2). Plug assembly (1) will not be needed for installation of the new parts.

NOTE: Plug (1) is removed so wiring from the engine timing control can be connected at this location on the magneto. If magneto (2) does not have a plug (1), it will be necessary to remove this magneto and install a new 7W2171 Magneto as a replacement.

It will be necessary, however, to inspect each 7W4377 Ignition Coil (3) on the engine, to make sure they are all the latest type coils. The latest type 7W4377 Ignition Coil has a raised portion, shown at location (A), at the base of the coil.

If the engine does not have the latest type 7W4377 Ignition Coils as described here, replace all ignition coils on the engine with the newer type coils.

The parts given in the following parts list will be needed to modify the ignition system so it is similar to current production engines.

Installed Location of Components for 3512 Engine with Converted Ignition System

The illustrations that follow show the location of all parts in a completely new ignition group for a 3512 Engine. The item numbers in the parts list are identified on the illustrations for ease of location. All conversions will not have all of these parts installed new, but, each ignition system will have all of these parts when the conversion is completed.

View from right side of engine. A. Front face of cylinder block.

View from rear of engine. B. Top view of flywheel housing.

Installation of Engine Timing Control on 3512 Spark Ignited Engine

If the engine was originally equipped with a fixed timing system, remove the magneto, wiring, etc. Install the new replacement parts, magneto, wiring harness, etc., with the exception of the 7C6662 Variable Timing Control Box. Refer to the parts list for your specific engine.

If the engine was equipped with one of the earlier variable timing systems, refer to the parts list for your specific engine.

Proceed to the following topic entitled Installation of 7C6662 Variable Timing Control Box.

Installation of 7C6662 Variable Timing Control Box

1. For those earlier engines so equipped:

* Disconnect cable (1) at the magneto. Temporarily remove the support clips that hold cable (1) in position.

* Remove electronic control box (2) and its mounting hardware from the engine.

* Use 0S1594 Bolts with 5M2894 Washers in the empty bolt holes that remain after the removal of electronic control box (2).

2. With two 0S1588 Bolts (7), with four 5M2894 Washers and two 1D4717 Nuts, fasten 7E0874 Plate (5) to 7E0875 Bracket (9).

Use four 3N1968 Mounts (8) and eight 9S8750 Nuts (4) with eight 5P0537 Washers to fasten 7C6662 Variable Timing Control Box (6) to bracket (9).

3. Using two 0L1351 Bolts with 5M2894 Washers, fasten the complete assembly to the cylinder head at cylinder number eleven.

4. One 4F4879 Bolt (10) with a 5M2894 Washer are needed to fasten one end of 2D7134 Strap (11) to the cylinder head. Fasten the other end of strap (11) under one of the control box mounting nuts as shown.

5. Use 0S0509 Bolt (14) with a 5M2894 Washer and 5D9297 Clip (13) to fasten harness (12) to the side of the flywheel housing.

6. Connect harness (12) to the magneto as shown.

Modification of Junction Box - 3512 Generator Set Engines

Use the procedure and the parts given in the following parts list to make the modification to the junction box.

NOTE: Identify and mark all external wiring harness connections at the junction box before starting the following procedure. It will be easier if the external harness connections are disconnected and the wiring harness is moved back out of the way.

1. Disconnect harness assembly (1) and remove it from the junction box. Disconnect wiring and remove relay (2) if so equipped. Discard harness assembly and relay as they will not be needed.

2. Remove two relays (4) and insulators (3) and set them aside because the will be needed again in the modification of the junction box.

3. Put 9Y8394 Plate Assembly (9) in position as shown. Use 4B2047 Nuts (7) with 9F8125 Lockwashers to fasten it in place. Install a 4W2215 Insulator (3) and 4W2217 Base (8) for each relay, then install 6T4007 Relays (4) and (11) as shown (one new, two original).

Use 4B2047 Nuts (7) with 9F8125 Lockwashers to fasten each relay in the junction box. Install a 4W2216 Spring (10) for each relay.

4. Install a new 5N4988 Diode Assembly (5). [The 5N4988 Diode Assemblies at location (A) are the original diodes and will still be needed.]

Connect 7E1120 Wire Assembly to terminals 5 and 9 on the terminal strip. Use jumper wires to connect terminal 28 to terminal 29, and terminal 30 to terminal 31.

5. Install 9Y8396 Harness Assembly (6). Make all wiring connections according to the wiring schematic that follows.

6. After all wiring connections are made inside the junction box, connect all external wiring that was disconnected for the modification procedure.

Installation of Gas Shutoff Valve Solenoid

It will be necessary to obtain the parts given in the parts chart that follows.

Install the gas shutoff valve solenoid as shown in the illustration.

Wiring Diagram and Component Location for 3512 Generator Set Engine

Supplemental Schematic-Optional Prelube Pump and/or Dual Starting Motors.

The parts needed are given in the parts chart and are shown in the illustrations in this topic.

* A 9Y7685 Wiring Harness is 6.1 m (20 ft) long. A maximum of five of these harnesses can be connected together to connect from the engine to the remote mounted 9X4286 Control Group.

NOTE: The 9X4286 Electronic Timing Control Group must be remote mounted. It must be mounted in a location that will permit the use of the 9Y7685 Wiring Harness to connect from the control group to the engine wiring harness connector. Use the specific wiring diagrams to make the correct connections.

Left Side View: 1. Left side detonation sensor. 2. Gas shut-off valve connector. 3. 7C4353 Clip. 4. 5M2894 Washer. 5. 7C4355 Clip.

Front View: 5. 7C4355 Clip.

Right Side View: 4. 5M2894 Washer. 5. 7C4355 Clip. 6. Right side detonation sensor. 7. Magneto connector. 8. 7E2852 Plug Assembly. 9. 9Y7690 Harness Assembly. 10. Timing control connector. 11. Digital diagnostic tool connector. 12. Crankshaft angle sensor. 13. Variable timing control box assembly.

Rear View: 14. 3S2093 Strap. 15. Magneto ground. 16. Magnetic pick-up.

For engine setup, it will be necessary to have a digital diagnostic tool. The tool needed is not the same diagnostic tool that is used for diesel or PEEC Engines. Make reference to the Service Manual for the setup procedure and digital diagnostic tool usage.