trusting someone else is what got it out of spec in the first place ...

i've done it maybe a dozen times and only one truck was out of spec, a '91 first gen that a buddy had ...

it was an auto and had half the power and twice the valvetrain noise that mine did ...

we adjusted the valves (my first cummins valve job) and it quieted right up and seemed to run better but made no difference in his mileage ...

 

I guess I waited a bit too long to do mine - approx 200k. Had a Cummins dealer do it. 1.5 hrs. labor. Three were out but not by much. It did run smoother and best of all I picked up a little over 1 m.p.g. when loaded, no difference empty. Been "preaching" to my Cummins friends ever since.

 

I did mine at 30k and it wasn't worth the bother. Two of them were about .002" loose. The rest of them were within .001". I was impressed! Craig

 

i need to do mine, but i will need some help from someone in my area. i am not too mech. inclined. but if i could get some help the first time then i could do it myself from there on out.
i would be worth a lunch or dinner depending on the time of day.

 

My dealer quoted me $90. I got prices from 2 Cummins shop's. One was $450, and the other was $200-$300. They called it running the overhead. They said part of that was doing something to the injector's. Anyone know what that might be.

 

Had a nearby diesel shop do mine for about $175. Didn't seem to notice a difference. I recommend doing it for super preventative maintenance.

BTW my truck had 120K at the time.

 

Engine warm or cold? Some engines are different. IIRC, my 12v was engine warm.

 

Did you tell the Cummins dealer it was on a pickup and not a semi? it takes a lot longer to do it on a semi then it does our 5.9L. Some shops when they run the rack on a semi also run cleaner through the injectors so that maybe why they gave you a higher price than dealership did.

 

I know that you are supposed to adjust them on a cold engine; but will it make a difference at a cold ambient temperature air or a hot one??? Or am I picking pretty small nits???

 

under 140 degrees F.

 

I did mine the other day and most of my exhaust valves were out of tolerance and only one intake was close to being out. Most of the intakes were around .011. I didn't notice a whole lot of difference but it does seem a little quieter. It is a pretty easy to do job. Just get some feeler guages and take your time.

 

When adjusting the valves, does the engine need to be cold, warm or hot, or does it make no difference?

Sorry, I asked a question that had already been answered. Didn't read all the posts.

 

Cold engine. Just to add a little contrast did mine recently 145,000km and none were out! Set intake to 0.010'' and exhaust to 0.020''. The max on 2 or 3 were out by .002''. I was happily impressed.