HOUSING 9W8440 - Caterpillar

The injector sleeve seals the engine coolant from the low pressure fuel system. If there is a leak path and the engine is running, the higher pressure fuel is forced into the lower pressure cooling system. If the engine is off, the remaining cooling system pressure may force coolant into the low pressure fuel system.To troubleshoot fuel in the coolant (or coolant in the fuel) remove the injectors and pressurize the cooling system to 103 kPa (15 psi). Inspect the injector sleeves for the following:1. Cracked Or Pitted Injector Sleeves2. Bad Sleeve To Head Joint May have to leave pressure on cooling system up to 30 minutes.3. Cracked Or Porous Cylinder HeadMake all injector sleeve repairs using the 4C4054 Unit Injector Sleeve Replacement Tool Group. Refer to Special Instruction, Form No. SEHS9246, Using The 4C4054 Unit Injector Sleeve Replacement Tool Group.