CM2250 valve guide seal progress

[JMBT]

The valve guide seal job is finally done!! I found exhaust valve seals on 2,3,4,5,6 that we’re bad. I ran the overhead this morning. Then cycled the priming pump 8 times, cranked for about 10sec. Shut it off, ran the pump once more and cranked about 5 sec and she fired up!! Smoked like a son of a bitch for a few minutes of idling then quit smoking. After idling up to operating temp, I did a leak down test and only lost about 200-250psi in 60 sec, before the job I was loosing about 1400psi in 60 sec. I am attributing this to replacing the fuel relief valve which I also did while I had the fuel system apart. I also did a cutout test and she performed beautifully. Tomorrow I put the wheels back on and take a road test.

[JHNDZ]

(01-20-2018 )JMBT Wrote:  JHNDZ, my truck has 648k. I am doing the valve guide seals because they have been leaking awhile and finally got so bad they started to push oil out of the exhaust manifold. I would not bother yours if they aren’t leaking regardless of miles. I don’t know what this would cost at a shop as I am doing it myself all at my brother’s.

.. Will do thanks for the reply ..
I'll wait and keep an eye on it ..

[Hammerhead]

(01-21-2018 )JMBT Wrote:  The valve guide seal job is finally done!! I found exhaust valve seals on 2,3,4,5,6 that we’re bad. I ran the overhead this morning. Then cycled the priming pump 8 times, cranked for about 10sec. Shut it off, ran the pump once more and cranked about 5 sec and she fired up!! Smoked like a son of a bitch for a few minutes of idling then quit smoking. After idling up to operating temp, I did a leak down test and only lost about 200-250psi in 60 sec, before the job I was loosing about 1400psi in 60 sec. I am attributing this to replacing the fuel relief valve which I also did while I had the fuel system apart. I also did a cutout test and she performed beautifully. Tomorrow I put the wheels back on and take a road test.

So when are you comin to help do mine? You have the most experience now after all...

[JMBT]

Sounds like a plan Hammer!! You buy the beer, but let’s wait until spring or summer!!!

[JMBT]

So the test run today was a success!! The old girl ran great!! Still smoked a bit after idle, but I am hoping that was just the extra assembly lube I put on the valves with the new seals. We’ll see tomorrow!