The overhaul interval that is listed in this Operation and Maintenance Manual, "Maintenance Interval Schedule" is expressed in fuel consumption and service hours. The more accurate figure to use is fuel consumption. Fuel consumption corresponds more accurately to the engine load.
Table 1 lists an average range of fuel consumption for a reasonable load factor before a top end overhaul. Use the range of fuel consumption only as a guideline.
| Approximate Fuel Consumption Before A Top End Overhaul | |
| Engine Model | Fuel Consumption (1) |
| 3618 | 12 605 000 to 14 763 000 L 3 330 333 to 3 900 000 US gal |
| ( 1 ) | The fuel consumption is based on fuel with a low heat value of 42 780 kJ/kg and density of 838.9 g/L. |
A top end overhaul involves the removal, the inspection, and the rework of the cylinder head components. Some additional components are replaced and serviced.
Your Caterpillar dealer can provide these services and components. Your Caterpillar dealer can ensure that the components are operating within the appropriate specifications.
Note: The driven equipment may also require service when the engine is overhauled. Refer to the literature that is provided by the OEM of the driven equipment.
The following definitions explain the terminology for the services that are performed during an overhaul:
Inspect - Inspect the components according to the instructions that are in Caterpillar reusability publications. Refer to Guidelines for Reusable Parts and Salvage Operations, SEBF8029, "Index of Publications on Reusability or Salvage of Used Parts". The guidelines were developed in order to help Caterpillar dealers and customers to avoid unnecessary expenditures. New parts are not required if the existing parts can still be used, reconditioned, or repaired. If the components are not in the reusability guidelines, refer to the Service Manual, "Specifications" module.
Rebuild - The component is reconditioned in order to comply with reusability guidelines.
Replace - The service life of the part is exhausted. The part may fail before the next maintenance interval. The part must be replaced with a part that meets functional specifications. The replacement part may be a new part, a CAT remanufactured part, a rebuilt part, or a used part. Some worn components may be exchanged with your Caterpillar dealer for a credit on replacement parts. Consult your Caterpillar dealer about repair options for your engine.
If you elect to perform an overhaul without the services of a Caterpillar dealer, be aware of the recommendations in Table 2.
| Recommendations for the Top End Overhaul | |
|---|---|
| Service | Component |
| Inspect Replace |
Cylinder sleeves |
| Exhaust shields | |
| Starting motor | |
| Turbocharger bearings, bushings, and seals | |
| Clean Inspect |
Oil cooler core |
| Oil suction screen | |
| Rebuild Cylinder heads |
Exhaust valves (1) |
| Exhaust valve seat inserts | |
| Inlet valves (1) | |
| Inlet valve seat inserts | |
| Inner valve springs | |
| Outer valve springs | |
| Valve spring guides | |
| Valve spring locks | |
| Valve rotators | |
| Replace | Cylinder head gaskets |
| Exhaust manifold gaskets | |
| Fuel injectors | |
| Fuel transfer pump seals | |
| Oil pump bearings and seals | |
| Oil temperature regulators and seals | |
| O-ring seals and plugs | |
| Seals for the inlet air lines | |
| Water pump bearings and seals | |
| Water temperature regulators and seals | |
| Replace the gaskets and seals. | Exhaust Bypass Valve |
| ( 1 ) | The angles of the valves and the seats are different. If the valves and the seats are not replaced, lap the valves and the seats. The valve and the outer diameter of the seat must have 360 degrees of contact. If the valves and the seats require grinding, see the Service Manual, "Specifications" for the angles. |