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Topic: Adjusting valves on 99 cummins ISM (Read 1344 times) previous topic - next topic

Adjusting valves on 99 cummins ISM

Just finishes adjusting my valves and everything went well.  I have about 110k on her and all the exhaust valves were perfect at.027 so noadjustment was needed.  However, all the intakes were set at .007 and hence all required adjusting to .014.  My concern is why were they all at .007?  It states on the engine plate that .014 and .027 are the correct settings.  If only one or two were off i would not be concerned but with all being .007 I wonder if I am missing something.  I did not mess with the injector settings.
 
Any suggestions or support would be helpful.

Thanks for your help
Jason
Jason
1999 U320 36'

Re: Adjusting valves on 99 cummins ISM

Reply #1 –
Should run/sound a little better,wonder when it was adusted last and by who.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Adjusting valves on 99 cummins ISM

Reply #2 –
Probably get a lot of disagreement on this but, I don't see any performance gain technically a slight loss. The Valve lash settings are mainly to transfer heat from the valve to the head. The intake valves don't get near as hot as the exhaust valves. The .007 less valve lash on the intake actually increased your lift and duration on the intake side of the cam. Valve lashes are played with on performance engines in race cars while on the dyno. 
Just my opinion.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adjusting valves on 99 cummins ISM

Reply #3 –
Not disagreeing but they are also set by the composition of the valves and metal around them,these were 50% off.

Was the engine completely cold?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Adjusting valves on 99 cummins ISM

Reply #4 –
I wasn't recommending, just commenting that he wouldn't feel any difference. When I set mine they will be .014 and .027 and 120 deg. on the injectors. Factory specs.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Adjusting valves on 99 cummins ISM

Reply #5 –
I worked on import autos professionally from 1970 until three years ago. They were, for the most part, required to check the  adjustment every so many miles. I would say if the factory spec on those intakes were .014 cold, and when you checked them they were all on .007, you might say they definitely needed adjusted. As far as why were they all at .007? I'm with you about those valves all changing by .007. Its very unlikely. Just be glad you checked them. And now I wonder if I should check mine.......... by the way the sticker on the engine should supersede  any previous data on valve lash.

Dennis Davis
99 270


Dennis Davis
1999 U270 36'

Re: Adjusting valves on 99 cummins ISM

Reply #6 –
Quote from: craneman –
Probably get a lot of disagreement on this but, I don't see any performance gain technically a slight loss. The Valve lash settings are mainly to transfer heat from the valve to the head. The intake valves don't get near as hot as the exhaust valves. The .007 less valve lash on the intake actually increased your lift and duration on the intake side of the cam. Valve lashes are played with on performance engines in race cars while on the dyno. 
Just my opinion.
I always run my exhaust on the loose side...intake dead on..
Hans & Marjet
1995 U300 "Ben" (#4719)
3176B Cat,4060HD,Jake
SKP#139131
Motorcade#17579
2006 Honda Element (towed)

Re: Adjusting valves on 99 cummins ISM

Reply #7 –
You can't go wrong doing that.
Dennis Davis
1999 U270 36'

Re: Adjusting valves on 99 cummins ISM

Reply #8 –
Get ready for some import car questions.
96 U270 BUILD 4810
85 380SL
Drummonds TN.