Testing Fuel System For Leakage - Komatsu Galeo PC800-8 Shop Manual

SEN00786-02

Testing fuel system for leakage

k Very high pressure is generated in the high-
pressure circuit of the fuel system. If fuel leaks
while the engine is running, it is dangerous
since it can catch fire.
After testing the fuel system or removing its
parts, test it for fuel leakage according to the fol-
lowing procedure.
a Clean and degrease the engine and the parts
around it in advance so that you can test it easily
for fuel leakage.
1. Spray color checker (developer) over the fuel
supply pump, common rail, fuel injector, and
joints of the high-pressure piping.
2. Run the engine at speed below 1,000 rpm and
stop it after its speed is stabilized.
3. Inspect the fuel piping and devices for fuel leak-
age.
a Check mainly around the high-pressure cir-
cuit parts coated with the color checker for
fuel leakage.
a If any fuel leakage is detected, repair it and
inspect again from step 1.
4. Run the engine at low idle.
5. Inspect the fuel piping and devices for fuel leak-
age.
a Check mainly around the high-pressure cir-
cuit parts coated with the color checker for
fuel leakage.
a If any fuel leakage is detected, repair it and
inspect again from step 1.
6. Run the engine at high idle.
7. Inspect the fuel piping and devices for fuel leak-
age.
a Check mainly around the high-pressure cir-
cuit parts coated with the color checker for
fuel leakage.
a If any fuel leakage is detected, repair it and
inspect again from step 1.
8. Run the engine at high idle.
a Relieve the hydraulic pump.
9. Inspect the fuel piping and devices for fuel leak-
age.
a Check mainly around the high-pressure cir-
cuit parts coated with the color checker for
fuel leakage.
a If any fuel leakage is detected, repair it and
inspect again from step 1.
20
a If no fuel leakage is detected, check is com-
pleted.
30 Testing and adjusting
PC800, 850-8