Komatsu PC200-8M0, Shop Manual, Page: 379 / 1254

SEN06127-00
PC200, 200LC, 220, 220LC-8M0 30-101
27
101 Testing and adjusting, Part 1
Testing fuel circuit for leakage
Testing fuel circuit for leakage 1
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 dan-
gerous since it can catch fire.
After checking the fuel system or removing
its parts, check it for fuel leakage according
to the following procedure.
k Stop the machine on a level ground and
lower the work equipment to the ground.
a
Clean and degrease the engine and the parts
around it in advance so that you can check 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. Check the fuel piping and devices for fuel leak-
age.
a
Check mainly around the high-pressure
circuit parts coated with the color checker
for fuel leakage.
a
If any fuel leakage is detected, repair it
and check again from step 2.
4. Run the engine at low idle.
5. Check the fuel piping and devices for fuel leak-
age.
a
Check mainly around the high-pressure
circuit parts coated with the color checker
for fuel leakage.
a
If any fuel leakage is detected, repair it
and check again from step 2.
6. Run the engine at high idle.
7. Check the fuel piping and devices for fuel leak-
age.
a
Check around the high-pressure circuit
parts coated with the color checker for fuel
leakage.
a
If any fuel leakage is detected, repair it
and check again from step 2.
8. Run the engine at high idle and load it.
a
Relieve the arm circuit at the IN stroke
end.
9. Check the fuel piping and devices for fuel leak-
age.
a
Check mainly around the high-pressure
circuit parts coated with the color checker
for fuel leakage.
a
If any fuel leakage is detected, repair it
and check again from step 2.
a
If no fuel leakage is detected, check is
completed.