- Industrial Engine:
- C3.4 (S/N: CJR1-1,100-100,105-108,346-355,357-862,868-999,1001-1545,1547-1737,1740-1929,1931-1934,1937-2910,2912-2914,2916-3264,3267-3267,3274-3275,3277-3280,3284-3288,3292-3292,3294-3294,3296-3332,3334-5348,5350-5738,5759-5788,5790-5794,5796-5799,5802-6000,6002-6497,6499-6648,6652-6720)
There have been a number of isolated instances of issues with the fuel injection pump on certain C3.4 engines. The issue is water ingress into the internal components of the fuel injection pump.
To identify whether there is an issue with the fuel injection pump, follow the procedures in Systems Operation, Testing, and Adjusting, "Troubleshooting" and Engine News, SEBD9900, "Flow Control Valve (FCV) Solenoid on Certain C3.4 Engines".
If the fuel injection pump is suspect, remove the fuel inlet adaptor, the FCV (Stop) solenoid and the Cold Start Advance solenoid. Check the ports in the fuel injection pump for evidence of water ingress or contamination. Refer to the illustrations below for further guidance.
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| Illustration 1 | g03679537 |
Fuel inlet staining and small deposits (1) from contamination | |
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| Illustration 2 | g03679595 |
Contamination and deposits on a solenoid plunger | |
If excessive contamination is identified, install a replacement fuel injection pump.
Ensure that fuel of the correct specification is used and maintain all necessary fuel storage maintenance practices. These practices apply to machine tanks and bulk fuel tanks and include filtration and water separation. Refer to Caterpillar Engine Fluids Recommendations, SEBU6251.
Ensure that the water separator is checked and that fuel filters are replaced as recommended in the Operation and Maintenance Manual, "Maintenance Interval Schedule".
Where concerns about fuel cleanliness exist, use the SOS system to determine a suitable filter replacement schedule.