Fuel Dilution of Engine Oil May Occur on Certain C27 and C32 Machine Engines {1290} Caterpillar

Engine

C27 Engines

C32 Engines

Introduction

The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

Fuel dilution of engine oil occurs due to injector leaking fuel from worn or damaged O-ring seals.

Solution

Caterpillar^® is aware of this problem, but an interim repair has not been identified.

If fuel dilution of engine oil is suspected, submit a Dealer Solution Network (DSN) service request for additional troubleshooting assistance. Document the following information before submitting a DSN ticket.

1. Document the engine model, serial number, and injector part number.

2. Document the total number of engine hours along with number of engine hours since the last oil change.

3. How was the fuel dilution problem identified? If so, what repairs may have been made in the past? For example, new injector, new injector O-ring seals)

4. What is the current oil change interval (Hours)?

5. What is the application? For example, track-type tractor in a mining application. Does the application have a high proportion of idling? is the application exposed to very high temperatures? (i.e. underground mining, high operating/ambient temperatures)

6. What is the fuel transfer pump outlet pressure to the engine at idle and rated conditions?

7. What is the fuel transfer pump outlet pressure vs time after engine shut down (does the engine hold fuel pressure after shut down or does supply pressure quickly drop to zero)?

8. If Scheduled Oil Sampling (SOS) oil samples have not been taken, please take SOS oil samples. Refer to Special Instruction, REHS3007, "Determining the Cause of Fuel Dilution of Engine Oil".

9. If new injector or new injector O-ring are installed, refer to Disassembly and Assembly, RENR9217, "C27 and C32 Engines for Caterpillar Built Machines".

10. Provide pictures of injector external O-rings immediately after removal from engine along with injector part number and serial number. Return suspected injectors with suspected O-rings seals to Caterpillar for failure analysis. Let field service engineer know that return hardware is coming (claim number, injector serial number, injector part number).