52743 Mercruiser SCREW, WATER PUMP AND TIMING COVER TO CYLINDER BLOCK (3 3/4"

Introduction
This Special Instruction provides the procedure to repower a D10N Track-Type Tractor. The replacement engine will be a Tier II level 3412E engine. See table 1 for the engine arrangement numbers. The D10N Track-Type Tractor was 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.
Table 1
Engine Arrangement
Original Engine Replacement Engine
7W-2873 256-7535(1)
105-6574 N/A(2)
(1) New Repower Engine
(2) RemanThis 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. Additional 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.Safety
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.
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.
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.
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.
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.Required Parts
Refer to Parts Manual, SEBP4387.Note: The required parts are subject to some change. Refer to TMI for the most recent required parts list.Note: 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.