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Topic: M-11 engine valves and injectors adjustment (Read 992 times) previous topic - next topic

M-11 engine valves and injectors adjustment

I'm at 120K on the engine and looking to adjust the injectors and valves.  Has anyone attempted this job?  I have the Cummins manual and procedure which appears to be straight forward.  Any tips or hints would be appreciated.  Has anyone had this done by Cummins and if so, what was the approximate cost.  Thanks!!   
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: M-11 engine valves and injectors adjustment

Reply #1 –
I recently had this done. Cost was approximately $600 but I had some coolant and fuel lines changed which was included in the price. Was in the shop about half a day.  This also included some gaskets.
Felix and Gail Mathieu
99 U320
Jeep Liberty CRD
Build number 5522

Re: M-11 engine valves and injectors adjustment

Reply #2 –
If you've adjusted valves before and feel comfortable doing so it's not difficult. Depending on how much room you have to work and how flexible your body is may be the deciding factor. A couple of the valves may be difficult to reach. Follow the directions in the owners manual and it's really quite easy. If you're not sure you know what you're doing have it done by Cummins. The real danger is getting an adjustment too tight which could burn a valve. Too loose won't damage anything but could affect performance. I've adjusted the valves on the two M11 coaches we owned and both required very little adjustment to get perfect. Valve adjustment doesn't change much unless there's something bad going on.
Word of caution - make sure the engine and compartment is clean as possible with nothing loose above the engine. Be careful nothing falls in the valve area while the covers off.

David Bethard
2003 U320
David Bethard
2003 U320 - 40ft. Build #6159
ISM 500hp
2006 Jeep Liberty CRD
2021 Honda Goldwing DCT

Re: M-11 engine valves and injectors adjustment

Reply #3 –
Is 120K the recommended miles to adjust valves & injectors on an M-11?

best, paul
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: M-11 engine valves and injectors adjustment

Reply #4 –
yes, 120,000 is the recommended time to adjust.  I talked to Cummins too to confirm. I posted recently that just had this done a bit past time on the used coach we bought. 

They found the engine in good shape but the intakes a bit tight.  They noted I might see a bit of change in performance,  and perhaps mpg would be a benefit.

I was really glad to get this done.  Was interesting to watch some of the work.  Not something I would tackle for the cost but I am sure with right tools and information and talent you could do this.  THey got to this by raising the bed, working from inside, literally sitting in the engine compartment.  If you need more info, let me know.  Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: M-11 engine valves and injectors adjustment

Reply #5 –
Quote
yes, 120,000 is the recommended time to adjust. I talked to Cummins too to confirm. I posted recently that just had this done a bit past time on the used coach we bought.

They found the engine in good shape but the intakes a bit tight. They noted I might see a bit of change in performance, and perhaps mpg would be a benefit.

I was really glad to get this done. Was interesting to watch some of the work. Not something I would tackle for the cost but I am sure with right tools and information and talent you could do this. THey got to this by raising the bed, working from inside, literally sitting in the engine compartment. If you need more info, let me know. Mike

John Christman, you've recommended Pacific Power over Cummins to me if I recall aright. Would you recommend them for valve adjustment?

best, paul
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: M-11 engine valves and injectors adjustment

Reply #6 –
Just for info, the local Cummins Factory shop in Richmond Va, who knows my coach, tells me the whole valve adjustment process is no more than a 3 hour job, mainly due to there is nothing above the engine, the bed raises so access is simple, If had a helper to bar engine over, would take less time as would not have to run in / out to change cam position each time.
Cheers
Dave M

Re: M-11 engine valves and injectors adjustment

Reply #7 –
I have a estimate from the Richmond Va Cummins service center. Anywhere from $500-600. May consider tackling it myself. The manual calls for utilizing a torque wrench adapter P/N ST669. That tool new is $234 from Snap-On. Anyone out there have a used one?
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: M-11 engine valves and injectors adjustment

Reply #8 –
There are a bunch on E Bay, you just need to know the nut size.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: M-11 engine valves and injectors adjustment

Reply #9 –
I was looking for Cummins P/N ST669, but decided to go with a different torque adapter. Found a Torque Wrench Adapter Calculator on the internet. Essential when adding a adapter to a torque wrench to calculate the final torque at the nut.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD