Komatsu gd655 crank no start

[Skeet3361]

Hello I have a motor grader gd655 cranks but doesn't start. no smoke when cranking, I installed new batteries due to low cranking amps, replaced fuel filters and injection pump still have the same issue. any advice is greatly appreciated

 

[Pickawinna]

Is fuel system properly primed? Crack an injection line at cylinder head and pump the primer until only fuel and no air comes from injector line?

 

[Simon C]

Is there an electric solenoid on the fuel pump that opens the fuel passage. Maybe no power coming to the solenoid. Simple check with test light or meter. Could be wiring problem, or fuse problem. The solenoid is probably okay as the fuel shop would of tested it if it has one.
Simon C

 

[Skeet3361]

Yes system is primed properly cracked all injector lines fuel comes out. Solenoid does click with key on when turning over I can hear tapping noise coming from engine.

 

[cuttin edge]

Was it running before, and quit, did it have work done, and now it won't start, or did it just decide one day not to start?

 

[Simon C]

Did you change the main injection pump or a priming pump? If you have primed it, how did you fuel spill the pump if it was the injection pump. Just wondering, cause if done wrong, will never start.
We are not there so asking questions. As cutting edge said what started all of this.
Simon C

 

[Skeet3361]

Was working all day next day wouldn’t start Kirby came out and replaced filters and said that fuel was bad they drained and cleaned. Tech said that he had got it running but turned to off to clean fuel lines. Never started back up but the time I got to to batteries were drained. Put two fresh one on it primed system crank no start so I replaced injector pump and reprime same results.

 

[Skeet3361]

When I got to it the system was already primed. Just wouldn’t start customer ask me to replace main injection pump. After I installed it I cracked fuel filter to fill from hand pump. Then tighten it then cracked injector lines and primed getting fuel to injectors unit just won’t start. I have no idea what started it. Customer said to was running on day the next day wouldn’t start.

 

[Simon C]

I worked on some 705 Komatsu graders and 855 Komatsu Graders , and the fuel pumps had to be spill timed. Maybe yours is different. Would yours by chance be powered by a S6D125 Series engine as these are time differently. Don't have any info on a GD655 grader. Have overhauled all kinds of Komatsu engines, just not sure what you have.
Simon C

 

[Skeet3361]

26127554 that’s the ESN

 

[Simon C]

Probably a new electronic engine of some kind. How was the injection pump timed. Was it on #1 Cylinder of compression and not by chance on #6 cylinder overlap. May or may not be able to help.
All I can say is that if timing is out just a little no start.
Simon C

 

[B&B]

Probably a new electronic engine of some kind. How was the injection pump timed. Was it on #1 Cylinder of compression and not by chance on #6 cylinder overlap. May or may not be able to help.
All I can say is that if timing is out just a little no start.
Simon C

I'm not familiar with spill timing but if it's getting fuel at the injectors would you still see smoke with the timing off?

 

[thepumpguysc]

If the pump drive shaft was keyed, chances are good your timing is close.. could be the key fell out.?
If the drive was NOT keyed, u definitely need to go back thru the timing.