Trouble after partial rebuild

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Trouble after partial rebuild

Postby davecove » Wed Dec 23, 2020 5:13 pm


So, I spun the #3 piston bearing and had to replace it. While I was in there I had the piston journals turned* .010" to address the scarring caused by the spun bearing on #3 and replaced the main and piston bearing shells and a lot of gaskets and seals. I am now trying to get it started again and having a couple of issues I was hoping someone could help me with.

1) It starts, but then immediately tries to over-speed, even with the throttle lever all the way aft (idle).
2) The #1 cylinder puts out black smoke, the #3 puts out white smoke, and the #2 is just right.


*the mains were still in spec despite the oil hole in the rear main bearing shell not being lined up with the oil feed hole in the block. :shock:

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Re: Trouble after partial rebuild

Postby Aaron » Mon Dec 28, 2020 10:08 am

Did you do anything to the injection pump (take it apart, clean it, adjust it)? Sounds like either the pump was taken apart & not assembled correctly, the governor is not connected correctly (or got damaged during pump removal), or the injection pump rack is stuck/sticky (should slide just by tipping the pump side to side).

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