- Wheel Dozer
- 844 (S/N: 2KZ1-UP)
- Wheel Loader
- 990 (S/N: 7HK1-UP)
- 990 Series II (S/N: 4FR1-UP)
Introduction
This Special Instruction provides the procedure to repower an 844 Wheel Dozer, 990 Wheel Loader, and a 990 Series II Wheel Loader. The replacement engine will be a Tier II level 3412E engine. See table 1 for the engine arrangement numbers. The 844 and 990 were originally equipped with a 3412 engine. The original 3412 engine is not regulated for emissions. This Special Instruction will provide the information to install the Tier II level replacement engine.
Engine | Engine Arrangement | |
Model | Original Engine | New Engine |
3412 | 4P-4990
122-1117 |
184-6458 (1)
|
(1) | New Repower Engine - Requires Software |
(2) | Reman Engine - Requires Software |
This Special Instruction does not include procedures that can be found in your existing manuals. Refer to the original Service Manual, Parts Manual, and Operation and Maintenance Manual for more information.
When you have completed this procedure, prepare the machine for service. Refer to the Operation and Maintenance Manual.
Note: Do not perform any procedure in this Special Instruction until the information has been read and understood.
Reference: Service Manual, Parts Manual, Operation and Maintenance Manual.
Note: This instruction contains some procedures that come from dealer feedback. The emissions replacement engine is not a direct replacement. Extra parts and labor hours may be needed to complete this engine replacement. Variations in machine serial number breaks or options could cause discrepancy in the modifications, required parts, and labor hours to complete this procedure. This documentation is a guideline for Cat Dealer personnel to complete the repower procedure. If errors are found, submit feedback in SIS web or contact the Emissions Solutions Group.
The information that follows will be required:
- Machine Serial Number
- Original Engine Arrangement Number
- Original Engine Serial Number
- Emissions Engine Arrangement Number
- Details of the Error
- Photos of the Error and the Photos After the Proposed Solution
New Engine Information Label
This repower process will require the engine to be reflashed with new software. Use a new engine information label by using the standard process before performing the repower.
Registering the Repower Machine
Reference: Special Instruction, REHS5097, "Instructions to Register the Retrofit"
Document changes to a machine configuration are an advantage to AVSpare and the dealer technicians that are sent to repair a machine. By identifying that the machine has been reconfigured, the technician will have a better opportunity to have the correct parts, tooling, and service information. Identifying that the machine has been reconfigured will also allow AVSpare to include the retrofitted serial numbers in applicable Service Letters.
Safety
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Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury to persons on or near the machine. To prevent injury or death, make sure that the area around the machine is clear of personnel and obstructions before operating the machine. |
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Do not attempt to assemble this machine until you read and you understand the assembly instructions. Improper assembly procedures could result in injury or death. |
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Personal injury or death can result from improper lifting or blocking. When a hoist or jack is used to lift any part or component, stand clear of the area. Be sure the hoist or jack has the correct capacity to lift a component. Install blocks or stands before performance of any work under a heavy component. Approximate weights of the components are shown. Clean all surfaces where parts are to be installed. |
NOTICE |
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Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products. Dispose of all fluids according to local regulations and mandates. |
Welding on Electronically Controlled Engines
Proper welding procedures are necessary to avoid damage to electronic controls. Perform welding on the engine according to the following procedure.
- Set the engine control to the "STOP" mode.
- Turn OFF the fuel supply to the engine.
- Disconnect the negative terminal from the battery.
- Disconnect the engine electronic components from the wiring harnesses: ECM, throttle actuator, actuator for the turbocharger compressor bypass, fuel metering valve, and sensors.
- Protect the wiring harnesses from welding debris and/or from welding spatter.
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NOTICE Do NOT use electrical components (ECM or sensors) or electronic component grounding points for grounding the welder.
- Connect the welder ground cable directly to the engine component that will be welded. Place the clamp as close as possible to the weld to reduce the
5 mm (0.20 inch) possibility of welding current damage to the engine bearings, to the electrical components, and to other engine components. - Use standard welding procedures to weld the materials together.
Original Machine Cycle Times
- Refer to the Service Manual for your particular machine to record cycle times.
- Record the cycle times for the original machine.
Original Machine Stall Speeds
Refer to SIS for Techniques for Loading Engines, SEHS7050-00.
NOTICE |
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Do not leave the machine in a stall condition for prolonged period. Only stall the machine to record the engine speed and boost pressure. Monitor the torque converter oil and cooling system. Do not allow the converter oil or the cooling system to overheat. |
- Refer to the Service Manual for your particular machine to record stall speed.
- Record the stall speed for the original machine.
Parts Needed
Reference: Parts Manual, SEBP5515
Note: The required parts are subject to some change. Refer to TMI for the most recent required parts list.
If part fabrication is necessary, ensure that all fabricated parts are deburred. Use caution when deburring parts. Avoid excessive grinding and notches.
Note: A breakdown of the kit provides a parts list for the repower. The kit part number is not serviceable. Order the engine arrangement plus the list of parts provided in the kit.
Repower Parts
( 264-1320 Conversion Ar-Repower) |
|||
---|---|---|---|
Qty | Part Number | Part Name | Description |
1 | Engine Ar | New Repower Engine - Requires Software | |
1 | Engine Ar | Reman Engine - Requires Software | |
Required Parts | |||
1 | Kit-Conversion (Repower) | This kit is non serviceable and provides a breakdown of the serviceable parts required for the repower, excluding the engine and optional groups. For line drawings and group structure refer to 264-1320 Engine Conversion Ar. | |
Optional Parts | |||
1 | Ether Starting Aid Gp | Includes components for ether aid. |
The following table shows the optional arrangements that are available for your machine. Before you start, determine the components that are needed for your machine.
Note: Some optional waste handler group parts are replacements for the components that are called out in the standard conversion group.
Procedure to Install the 3412E Repower Engine in the Machine
Preparation of the Machine
- Wash the machine.
- Remove the hood and the guards.
- Reclaim the used engine coolant.
- Disconnect all water lines.
- Remove the cooling system.
- Drain the engine oil into a suitable container.
- Remove the oil and fuel filters.
- Remove the air cleaner.
- Disconnect the remaining lines and electrical wires that are connected to the engine.
Removal of the Original Engine
Note: Before you remove the engine, measure the position of the crankshaft from centerline to the right and left frame rails. Also, measure the height from the centerline of the crankshaft to the top of the main frame. Record all measurements.
- Remove the original engine. Refer to Disassembly and Assembly, SENR6643.
- Remove dirt and grease from the machine.
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Illustration 1 | g01847607 |
Preparation of the Engine
Note: The following steps use parts from the original engine. Inspect all components and replace the components that are used from the original engine.
- Install the crankshaft pulley from the original engine.
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Illustration 3 g01885733 - Install the alternator (1) from the original engine.
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Illustration 4 g01885720 - Install the A/C compressor (2) from the original engine.
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Illustration 5 g01885736 - Install the rear engine supports (3) from the original engine.
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Illustration 6 g01885738 - Install the 194-1604 Fumes Disposal Gp. If the machine is equipped with dual starters, then the tube (4) will need to be secured to the frame.
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Illustration 7 g01885742 - Install the starter (5) from the original engine.
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Illustration 8 g01885777 - Install the mufflers and the supports (7) from the 193-8597 Muffler Gp.
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Illustration 9 g01885778 - Install the exhaust lines (8) from the 196-3813 Air Lines Gp.
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Illustration 10 g01885815 - Install the air cleaner adapters (9) and the air cleaner elbows (10) from the original engine.
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Illustration 11 g01885833 - Install the air lines (11) from the 192-9010 Air Lines Gp.
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Illustration 12 g01885854 - Install the air cleaners (12). Use two 1P-9390 Outlet Gaskets from the original engine.
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Illustration 13 g01885857 - Install two 213-6353 Precleaner As (13) from the 206-5087 Air Cleaner Gp onto the engine.
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Illustration 14 g01886094 - Install the lines (14) for the dust ejector from the 196-3818 Dust Ejector Gp.
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Illustration 15 g01886095 - Install the original torque converter (15).
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Illustration 16 g01893296 - Install the original implement pump (16).
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Illustration 17 g01893297 - Install the original pilot pump (17).
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Illustration 18 g01893298 - Install the original steering pump (18).
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Illustration 19 g01893300 - Use two 8T-4779 Bolts (19) to install the 194-6800 Piston Pump Gp (20) on the back of the steering pump. The 194-6800 Piston Pump Gp is found in the 195-3069 Piston Pump Gp.
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Illustration 2 | g01885716 |
Frame Modifications
- Remove the pad for the radiator from the front right side. After the pad is removed, grind until the area is clean and flat. Inspect the pads after removal. When possible, reuse the pads.
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Illustration 21 g01893454 - If the pad is damaged during the removal, then fabricate a new pad.
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Illustration 22 g01893513 - Weld the original pad or the fabricated pad using the dimensions shown.
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Illustration 23 g01893516 - Remove the remaining pads for the radiator. After the pads are removed, grind until the area is clean and flat. Inspect the pads after removal. When possible, reuse the pads.
- If the pads are damaged during the removal, then fabricate new pads. Refer to Step 2.
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Illustration 24 g01893534 - Use the radiator pad from the front right side (3) to locate the remaining pads.
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Illustration 25 g01929633 - Locate the 9C-7863 Block (4). Weld the block onto the frame.
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Illustration 26 g01893793 - Fabricate a new mounting block with the dimensions that are shown above.
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Illustration 27 g01893839 - Using the dimensions shown above to locate and weld the fabricated 9U-1793 Block (6) on the frame. Refer to Step 8.
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Illustration 28 g01893858 - Weld a 9R-2613 Weld Boss onto the front engine support.
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Illustration 29 g01893973 - Fabricate a new mounting block with the dimensions that are shown above.
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Illustration 30 g01893993 - Use the dimensions that are shown above to locate the fabricated mounting block.
- Weld the mounting blocks onto the frame.
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Illustration 31 g01894136 Use the location (A) to locate the bosses on the frame. - Use the dimensions that are shown above to locate the five 9R-2613 Weld Boss (9).
- Weld the 9R-2613 Weld Bosses onto the frame.
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Illustration 32 g01904373 Use the location (A) to locate the blocks and the plates on the frame. - Use the dimensions that are shown above to locate the three 9U-1793 Blocks (10) and one 9C-4935 Plate (11) on the frame.
- Weld the 9U-1793 Blocks (10) and the 9C-4935 Plate (11) onto the frame.
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Illustration 33 g01904393 - Remove the two bosses (12) that are shown above.
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Illustration 34 g01904414 Use the location (A) to locate the bosses on the frame. - Use the dimensions that are shown above to locate the four 9R-4595 Bosses.
- Weld the four 9R-4595 Bosses onto the frame.
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Illustration 35 g01904419 - Fabricate four new hood mounting blocks.
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Illustration 36 g01904436 Use the location (A) to locate the mounting blocks on the frame. - Use the dimensions that are shown above to locate the four new hood mounting blocks (14).
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Illustration 37 g01904496 - The bumper will need to be extended around
144 mm (5.66928 inch) to protect the new cooling system.
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Illustration 20 | g01893373 |
Installation of the Engine
Note: Many of the following steps use the parts from the original engine. Inspect all components that are used from the original engine. Repair the damaged components or replace the components.
- Install the engine (1).
- Install the original engine harness and the engine sensors. The original hardware is used to secure the harness onto the engine.
- Connect the 40-pin connector from the original harness to the 40-pin connector from the new engine harness. The wires may need extended.
- Inspect the components. Replace the components, if necessary.
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Illustration 39 g01936758 - Connect the original harness to the components of the air conditioner. The components are the arc suppressor (4), clutch solenoid (2), and the hi/low pressure switch (3). These components are transferred from the original engine.
- Attach the403-GN(Green)from the original harness to the Alternator R terminal.
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Illustration 40 g01937633 - Attach the 301-BU(Blue) (5), 304-WH(White) (6), and the 207-BK(Black) (7) from the original harness to the starter terminals.
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Illustration 41 g01915053 - Install the original fuel lines (8).
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Illustration 42 g01937777 - Install the heater lines (9) from the old engine.
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Illustration 43 g01915116 - Install the lines for the air conditioner (10) from the 192-7381 Air Conditioner Lines Gp.
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Illustration 44 g01915120 - Install the original drive shaft (11).
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Illustration 45 g01938276 - Install the original cooler for the power train and torque converter lines.
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Illustration 46 g01915122 - Install the original pilot pump lines.
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Illustration 47 g01915124 - Install the lines for the original steering pump (13).
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Illustration 48 g01915133 - Install the original lines for the implement pump (14).
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Illustration 49 g01915153 - Install the hydraulic lines for the fan pump and the motor. The lines are found in the 192-5621 Hydraulic Fan Lines Gp.
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Illustration 50 g01915515 - Reuse the original hydraulic oil cooler lines (15) that come from the hydraulic tank. Install the hydraulic lines (16) from the 192-7380 Hydraulic Oil Cooler Lines Gp.
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Illustration 51 g01915517 - Install the supports for the firewall (17) from the 193-5494 Firewall.
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Illustration 52 g01918053 - Assemble the cooling system, brake lights, and the rear lights from the 191-5212 Cooling Ar, 8R-5645 Stop Lighting Gp, and the 183-3463 Flood Lighting Gp.
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Illustration 53 g01918494 - Install the assembled cooling system.
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Illustration 54 g01943229 - Cuts may be needed around the bumper to provide clearance.
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Illustration 55 g01918597 - Replace the 6-pin plug connector (22) from the 193-0133 Rear Chassis Harness As with the 102-8805 Receptacle Kit. The 102-8805 Receptacle Kit is found in the 193-0115 Rear Wiring Gp. Connect the newly installed 6-pin connector from the rear lighting harness to the original vehicle harness.
Note: The wires may need extended to complete the connections.
Show/hide tableIllustration 56 g01918625 - Install the lines for the Air to Air Aftercooler (23) from the 191-7806 Air Lines Gp.
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Illustration 57 g01918630 - Install the water lines (24) from the 191-7811 Water Lines Gp.
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Illustration 58 g01943658 - Install the water tank (25) and the water lines (26) from the 194-1016 Water Lines Gp.
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Illustration 59 g01918632 - Install the hood (27) from the 192-3808 Hood and Guard Gp.
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Illustration 60 g01918695 - Install the remaining lines from the water tank to the radiator (28). The lines are found in the 194-1016 Water Lines Gp.
Note: The hood is removed in the illustration to show the water lines.
Show/hide tableIllustration 61 g01918696 - Install the ether aid (29) from the 194-8726 Ether Starting Aid Gp.
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Illustration 62 g01918699 - Install the shield divider (30) from the 192-7358 Engine Compartment Shield Gp.
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Illustration 63 g01918973 - Install the firewall (31) from the 193-5494 Firewall Gp.
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Illustration 64 g01919154 - Install the exhaust extensions (32) from the 194-7653 Exhaust Extension Gp.
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Illustration 38 | g01904915 |
Repower Pinouts
J1/P1 | |||
Pin | Usage | Circ. ID | Clr |
1 | ATA Data Link - | E793 | BU |
2 | Ground Level Shutdown NO | F715 | PU |
3 | Cat Data Link - | 892 | BR |
4 | + Battery | 150 | RD |
5 | - Battery | 229 | BK |
6 | + Battery | 150 | RD |
7 | ATA Data Link + | E794 | YL |
8 | Ground Level Shutdown NC | F716 | WH |
9 | Cat Data Link + | 893 | GN |
10 | N/A | N/A | N/A |
11 | - Battery | 229 | BK |
12 | TDC Probe - | F724 | PU |
13 | N/A | N/A | N/A |
14 | N/A | N/A | N/A |
15 | N/A | N/A | N/A |
16 | N/A | N/A | N/A |
17 | Fuel Pressure | F725 | WH |
18 | TDC Probe + | F723 | PK |
19 | N/A | N/A | N/A |
20 | N/A | N/A | N/A |
21 | N/A | N/A | N/A |
22 | N/A | N/A | N/A |
23 | Key Switch | 113 | OR |
24 | N/A | N/A | N/A |
25 | N/A | N/A | N/A |
26 | Coolant Flow Switch | 412 | BU |
27 | N/A | N/A | N/A |
28 | N/A | N/A | N/A |
29 | Digital Sensor Return | 998 | BR |
30 | Analog Sensor Return | 993 | BR |
31 | Oil Temp Sensor | E795 | YL |
32 | Speed Timing Sensors +12V | 996 | GN |
33 | N/A | N/A | N/A |
34 | N/A | N/A | N/A |
35 | Digital Sensor Supply +8V | A700 | OR |
36 | Analog Sensor Supply +5V | 997 | OR |
37 | Rail Pressure Sensor | E796 | GN |
38 | Primary S/T Sensor | 999 | WH |
39 | Backup S/T Sensor | F732 | PK |
40 | N/A | N/A | N/A |
J2/P2 | |||
Pin | Usage | Circ. ID | Clr |
1 | N/A | N/A | N/A |
2 | N/A | N/A | N/A |
3 | Inlet Air Temperature | C967 | BU |
4 | N/A | N/A | N/A |
5 | Injector Common 1&3 | F726 | YL |
6 | N/A | N/A | N/A |
7 | PWM and Solenoid Return | E799 | BR |
8 | Oil Pressure Sensor | 994 | GY |
9 | Coolant Temp Sensor | 995 | BU |
10 | N/A | N/A | N/A |
11 | Injector Common 2&4 | F727 | BU |
12 | Injector #12 | A712 | BR |
13 | N/A | N/A | N/A |
14 | N/A | N/A | N/A |
15 | Fuel Temp Sensor | A751 | YL |
16 | Injector #1 | A701 | GY |
17 | Injector Common 5&7 | F728 | BR |
18 | Injector #10 | A710 | GY |
19 | N/A | N/A | N/A |
20 | Atmospheric Pressure Sensor | A747 | GY |
21 | Injector Common 6&8 | F729 | GN |
22 | Injector #8 | A708 | BR |
23 | Turbo Outlet Pressure Sensor | A746 | PK |
24 | Accelerator Pedal Position | F702 | GN |
25 | N/A | N/A | N/A |
26 | Injector #3 | A703 | BR |
27 | Injector Common 9&11 | F730 | GY |
28 | Injector #6 | A706 | GY |
29 | Rail Pressure Control Valve | E798 | PK |
30 | N/A | N/A | N/A |
31 | Injector #1 | A711 | PU |
32 | Injector #5 | A705 | BU |
33 | Injector Common 10&12 | F731 | OR |
34 | Injector #4 | A704 | GN |
35 | Rail Pressure Control Valve-Return | E797 | WH |
36 | N/A | N/A | N/A |
37 | Injector #9 | A709 | OR |
38 | Injector #7 | A707 | PU |
39 | N/A | N/A | N/A |
40 | Injector #2 | A702 | PU |
Hydraulic Fan Speed
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Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak. |
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Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. In order to prevent possible injury, perform the following procedure before testing and adjusting any of the machine hydraulic systems. |
NOTICE |
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Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products. Dispose of all fluids according to local regulations and mandates. |
- Park the machine on a smooth, level surface. Move away from other operating machines and away from personnel. Lower the bucket to the ground. Stop the engine.
- Permit only one operator on the machine. Keep all other personnel away from the machine or in sight of the operator.
- Engage the parking brake. Put blocks in front of the wheels and behind the wheels.
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Illustration 65 g00852083 Steering frame lock in the LOCKED position - Install steering frame lock in the LOCKED position so the machine cannot articulate.
- Depress the brake pedal repeatedly will relieve any pressure that may be present in the brake hydraulic system.
- Move the implement control levers through the full range of travel will relieve any pressure that may be present in the implement hydraulic system. Place the lift control lever in the HOLD position. Place the tilt control lever in the HOLD position.
- Turn the steering controls several times in both directions to relieve the pressure in the steering system.
- Slowly remove the hydraulic tank cap to relieve any pressure in the hydraulic oil tank.