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Fuel problem on M-11 Cummins

JBGASH ยท 2012-09-08 05:37

I have a 95 IH road tractor with a M-11 Cummins engine that after it sets overnight the next day it acts like the fuel pump looses prime. I give it a small shot of either and it starts and runs excellent for the day. Anyone have any ideas on what may be causing this?

Replies9
  1. #1miro2012-09-08 08:16

    This should be a Celect electronic engine. There is a cooling plate behind the computer on the right side of the engine. That cooling plate uses fuel from the fuel tank to cool the computer, then it goes to the fuel pump. Find the fitting going into the cooling plate from the tank, it is a 90'fitting and should have a check valve in it. the check valve was made of plasic and with time they break up. Just replace that fitting and you should be on your way

  2. #2JBGASH2012-09-08 23:12

    Thanks miro. Will do

  3. #3Reel hip2012-09-11 20:23

    Great info Thanks. Mine has the same problem. I don't start it with quick start though. I can give some throttle and after a 1/2 minute in the morning it is fine the whole day.

  4. #4JBGASH2012-09-11 22:28

    Update: Took it to the diesel repair shop and after some tests on the fuel system they say it needs a fuel pump rebuild. The cost is estimated at $500 or less to do the job. Hopefully this will take care of the problem.

  5. #5Reel hip2012-09-12 16:32

    I don't understand if the fuel pump was going out why would it run fine the next day after the initual start up?

  6. #6miro2012-09-12 17:42

    Try the check valve first, that seems awfully expensive to fix a transfer pump. You can get an exchange for a lot less. That pump is a gear pump with and electric shutoff on top, no more no less, it does not have a check valve in it, it needs an external check valve

  7. #7JBGASH2012-09-12 22:37

    Well I ask the pump shop the same question, his reply was that the test he performed led him to the conclusion it was the pump itself. I will let you know if it fixes it.

  8. #8Reel hip2012-09-13 23:41

    Yes please. I'm thinking of changing the check valve on mine first as Miro sugested.

  9. #9JBGASH2012-09-20 00:11

    Update: the diesel repair shop was correct, the fuelpump was rebuilt and now starts and runs like it should. The main pump shaft had wore severely and was allowing leak by, the shaft was replaced with an updated spline shaft and gear. They saved the parts for us to see and after looking at them it was very clear why it would loose prime after sitting overnite. The total pump overhaul bill came to $622.00