Komatsu PC 138US-10 Low fuel Rail Pressure Codes

[iforgotu812]

I’ve got a PC 138US-10 that’s throwing the ca559 and ca2249 error codes. It starts fine and doesn’t blow any black smoke. It will run for about an hour when you first start it up the it will hiccup and bogg while digging and throw the codes. You can shut it off for a few mins and fire it back up and it will run for awhile and do the same thing. I changed both fuel filters and checked every line for leaks. The hand pump primes up and stays tight. Could it be the fuel pressure regulator causing this? I would think if it was the supply pump it would do it all the time and be hard to start up. What should the pressure range at the fuel rail be?

 

[John C.]

Understanding what the codes mean would be the first question I might ask if the machine was mine. Do you know how to get into the diagnostics?

 

[iforgotu812]

Yes. They are codes for low fuel rail pressure but could be caused by several different things. I was hoping it was just the fuel pressure regulator being it’s electrically controlled and would explain why it would go away for awhile when I shut off and then restart the machine back up. I don’t have a book on it and was wondering what the fuel rail pressure range should be.

 

[John C.]

Sorry I can't help on this. Brain cells are far older than your machine. Hopefully someone will be along to give you some help.
Good Luck

 

[funwithfuel]

I'd be checking the tank for floating/suspended debris. Drain the tank and look see. Check the shut-off valve , make sure it's fully open. Make sure your filler cap is clean and the vent filter is not plugged solid with dirt.

 

[funwithfuel]

Rail pressure is dictated by fuel forced into rail. No metering valve aside from injectors. The safety valve is a high pressure dump valve. No electricity. Start with cleanliness, see what turns up
Good luck

 

[PLCunningham]

Did you solve what was happening with your pc138?
My pc138 is having exact some symptoms as yours

 

[Simon C]

Have you done the testing suggested by funwithfuel above. Would be a good starting point. Do you have codes to post up?
Simon C

 

[PLCunningham]

I have checked all of the above.
Just wondering if iforgotu812 had any luck?