Engine/Transmission (1998.5 - 2002) When to adjust valves on 2001 24 valve

[krtcummins]

I know Cummins calls for a valve adjustment at 150,000 miles. But, has anyone adjusted their valves sooner and if so, were they out of spec or could they have gone to 150,000 miles? I have 102,000 miles on mine and being old school, I feel compelled to check them and adjust if needed.

 

[davemac]

I did mine at 100K. They were all just a tad loose. Prolly coulda gone till 150k but my fuel mileage went up by 1-1. 5 mpg. Glad I had it done when I did.

 

[DMcLeod]

I checked mine at 130k. All within spec.

 

[krtcummins]

Thanks guys! A little loose is just fine. Tight clearences will burn valves. NOT a good thing. I was just amazed at Cummins' claim they will go 150,000 miles. Thats a long time to go between adjustments. Especially for a first adjustment. Some valves tend to seat in causing the cleaences to tighten up a tad. Especially on exhaust valves. Not a good thing.

 

[Sticks]

In all my years of engine work, I have yet to hit a Cummins engine at any mileage that was out of spec (Intake . 010, Exhaust . 020 +/- . 005).

Yes, even slightly abused engine and really bad driving habits they will still stay within specs.

 

[KcoleKennyc]

I have one with 241K that hasn't been checked and one with 421K that has been adjusted twice. I really do need to check them.

 

[Bob4x4]

In all my years of engine work, I have yet to hit a Cummins engine at any mileage that was out of spec (Intake . 010, Exhaust . 020 +/- . 005).



Yes, even slightly abused engine and really bad driving habits they will still stay within specs.

I guess all the out of spec trucks get shipped to California :-laf

I work on Dodge CTD's every day and that is quite a bit different than what I see

 

[Sticks]

I guess all the out of spec trucks get shipped to California :-laf
I work on Dodge CTD's every day and that is quite a bit different than what I see

Not saying I did not adjust them (customer paid for it). Just sayin' they weren't out of the tolerances.

I've did mine 2x just for something to do (still under 80k). Not including the 5 times during and after the head stud install.

My current employer has several industrial engines (Cummins 4 & 6 BT) in various pieces of equipment, some with over 10k hours on them, and they were still in spec.

 

[Bob4x4]

I have seen all MY's out of spec. but the worst has been the crd's. I UNDERSTAND they are set by machine at the factory. The huge acceptable range bothers me a bit. I have seen them right off the transporter rattling like crazy,2 trucks with pushrods spit out.

 

[drag racer]

I did mine when I changed injectors at less than 20k. They were all within spec. , but varied all over the place, so it was nice to set them all to the same value, and I could tell from the idle sound that it made a difference.