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Steve Ownby · 08-29-2018, 07:44 PM

I asked for recommended Cummins shops along I40a few days ago & got good feedback. Will go to the Albuquerque shop in mid Oct.

Anyone got a ballpark $$ figure for this service. Mine is an ISM but should be similar to any with a Jake brake.

Thanks,

Steve Ownby
‘03 Sig

BFlinn181 · 08-29-2018, 08:40 PM

Do you mean a valve adjustment? They may be overhead valves, but it's the valves that get adjusted, not the overhead.

BRex45 · 08-29-2018, 08:48 PM

Well the shop has overhead too. That needs to be factored in.

Have not heard of an overhead adjustment but did have my neck and back adjusted awhile back.

On a more serious note, and people will take you more seriously on-line or at a diesel shop if you refer to this procedure as a valve adjustment.

I used to be able to adjust valves on an 855 cu. in. Cummins in about an hour, including Jakes. Of course that was on a conventional semi with nothing between me and the engine except maybe an intake boot and a few wire ties.

Cummins NW in Portland charges about 30-40 dollars more per hour when working on a motorhome. Now THAT is an adjustment!

ziaptrn · 08-29-2018, 08:52 PM

When I called and scheduled a valve lash adjustment at Rush Truck Center several years back, they said "Oh. You mean an 'Overhead'"
So...I learned that for some in the business, "overhead" means what I call "valve lash adjustment"
Just to say that I've heard the same thing as the OP - and yes, I was confused when I first heard it!!! It makes no sense to me....but I'm from the south where we say things like "she just up and died" :-)

Steve Ownby · 08-29-2018, 08:53 PM

Quote:

Originally Posted by BRex45

Well the shop has overhead too. That needs to be factored in.

Have not heard of an overhead adjustment but did have my neck and back adjusted awhile back.

On a more serious note, and people will take you more seriously on-line or at a diesel shop if you refer to this procedure as a valve adjustment.

I used to be able to adjust valves on an 855 cu. in. Cummins in about an hour, including Jakes. Of course that was on a conventional semi with nothing between me and the engine except maybe an intake boot and a few wire ties.

Cummins NW in Portland charges about 30-40 dollars more per hour when working on a motorhome. Now THAT is an adjustment!

I got the term from Cummins maintenance literature. The valves are one adjustment but the Jake is adjusted and the injector stroke also since they are all under the valve cover.

Ray,IN · 08-30-2018, 09:45 PM

Have you read the valve adjustment schedule for your engine? For instance, valve lash adjustment for an ISX engine is at 500,000 miles.

Steve Ownby · 08-30-2018, 09:47 PM

Quote:

Originally Posted by ray,in

have you read the valve adjustment schedule for your engine? For instance, valve lash adjustment for an isx engine is at 500,000 miles.

ism is at 120,000.

ziaptrn · 08-30-2018, 09:56 PM

The 8.3L ISC manual calls for valve adjustment at 150k.

We did it at 105k (a little early).
As I understand it, there is no harm done if nothing needed adjusting (at worst, it would be wasted money). The rig is 14 years old and they had never been adjusted, and the Cummins guy (whom I trust) recommended it....even though they didn't do the adjustment. As it turned out, a few were out of adjustment and we did pick up about 1 mpg after adjusting plus a possible slight decrease in valve train noise. The decrease in noise also could be my wishful thinking, having invested the $$$ :-) but the mpg was objectively measurable.

I'm more of a maintenance kind of guy and like to stay a little ahead of the game if possible. I do understand that it wasn't genuinely 'necessary' when we had it done.

Thanks for the feedback and discussion....I always learn something here!

Dale70 · 08-31-2018, 06:29 PM

ziaptrn

What was the charge for the "valve" adjustment?? and where was it done --- ie truck service place? Cummins RV place?

thx Dale

ziaptrn · 08-31-2018, 06:54 PM

Oops. Guess I forgot and left that out. Rush Truck Center did the work; the cost was (if I recall correctly) 350.00. Sometimes I have trouble remembering what I had for breakfast....and this was about 2 years ago.
I priced an adjustment recently and it was $400.00. I believe this may vary widely depending on location, part of the country, etc.
My apologies for failing to respond to the initial question in the posting...which was... "how much"!

Dale70 · 09-01-2018, 07:02 AM

Thanks for the info --- I need to find a truck service place to do that around here. I think Cummins wanted $650-750.

I have an ISC with almost 140,000 MI. -- almost time

thx Dale