D11N governor issue

[Nige]

Hello all, So I looked at the turbos today. My book shows a end play spec of .0065” (+-.0025) the right side one seems about right but the left one has end play of about .030” could excessive end play cause low boost when warmed up? I’m thinking I need a new turbo..

If you go back to page 1 you responded to one of my questions that when the RPM dies the engines DOES NOT smoke heavily until the RPM recovers. That lack of smoke indicates to me a lack of fuel, not a lack of boost.

As a comment on your turbos. The one with the higher-than-spec end float probably does need replacing but on an engine like that one I would always recommend replacing turbos in pairs unless there was a really good reason not to such as a low-hour (after rebuild) turbo failure.

Sorry for harking back to it but the first thing that engine needs IMO is to have all the injector control linkages (see Page 1) checked and adjusted if necessary, followed by an injector set. If that doesn't solve the problem my gut feeling is, that with 17k hours on it since the last time it was rebuilt, it's just plain tired and needs rebuilding again. Again repeating myself, your challenge is to find a guy who actually knows how to adjust the MUI rack controls.

 

[Rihpper]

Yes that makes sense, Quinn supposedly has someone with experience adjusting them, he’s supposed to be giving me a call. Thanks again

 

[Rihpper]

Well, the Quinn tech came out and adjusted the valves, injector height, injector rack settings and checked the governor fuel setting. The rack settings were
the only thing that needed much adjustment. But after all that it still isn’t running right. Maybe a little better but still not revving up like it should and still very little smoke.

He checked the turbo and said he recommended replacement of that first then the injectors. The injectors seem to leaking, the oil under the valve covers had fuel mixed in with it. But we took a engine oil sample and it came but with no fuel in the oil...,

 

[Rihpper]

Well, I installed a Reman turbo. No improvement.

 

[Rihpper]

Well, good news! Its fixed.
I took the governor diaphragm off again looking for clues and I realized the gasket under the diaphragm cover had one small hole, but the gasket was rotated so the the gasket was blocking the hole in the governor housing that allows boost pressure to operate the diaphragm. So I rotated the gasket to align with the small hole and now with the shank 6’ in the ground at low idle it takes 5 seconds to get moving and reach 20psi boost. Now I only changed the diaphragm after I was having problems, so it wasn’t the original issue, ( it must have been the turbo or the injector settings) but I’m happy to be done with it. A big thank you to all who helped me sort it out!

 

[Nige]

Glad to hear that you got it sorted.

 

[Gary Layton]

This has been an amazing thread. I know squat (basically zilch) about dozers...ten years ago my son and I got my uncle's D7 cranked after many years of no-go. It ran great but took a 40-acre field to maneuver it back to its start point. I hope to try to resurrect it again before too long. I gotta feeling you guys here will be able to give us good input on how to make that beast steerable when we try again. Thanks to the OP for following thru on how you got it running right...and to Nige and the minions that helped this along.