Engine/Transmission (1994 - 1998) valve adjustment

[38flathead]

what is the recommended period that a12v should have valves adjusted my motor seems to sound louder at idle than normal. When I cruise at higher rpms the noise seems to disapate could it be something else motor preforming fine

 

[fest3er]

what is the recommended period that a12v should have valves adjusted my motor seems to sound louder at idle than normal. When I cruise at higher rpms the noise seems to disapate could it be something else motor preforming fine

IIRC, it's something like 50,000 for the first adjustment and every 100,000 after that. If they're well adjusted, they won't change much over time after the engine's broke in.



[EDIT: Boy am I wrong! See the FAQ item. ]



The sound is about normal. Mine's a little raucous at idle but quiets down and smooths out once it's moving.

 

[GAmes]

I have 50k checks on my homemade schedule, but since I rarely need to adjust any, and then only a tiny bit, I,m thinking 100k will work for me.

 

[Dieseldemon]

Cummins says evert 24000 miles for the 12v but I have found that after the first adjust at 24000 then every 60 or 70000 miles not much change after the first 24000

 

[surfbeetle]

I usually do mine every year regardless of mileage. I average about 10,000 miles per year. If I happen to miss for a while, nothing is hurting. Most times, it is just a check on the valve lash and nothing has changed. There have been a few times that things have changed and the engine runs much smoother after the fact.

 

[Texis]

I have 320,000 on my 12V without ever adjusting the valve lash, so I would say it's a bit over due. The point is don't sweat it, it's not an oil change. Do it when it's convenient for you.



I ask my local Dodge dealer's Cummins mechanic about the valves and he actually said: "on the old 12 valves if it ain't broke don't fix it, less you just want to" Now, I would not consider that good advice, but rather his experience talking. It was simply a non-issue to him. He did say they respond well to valve lash adjustment and it would perk the engine up.



Think I'll do mine this spring when the weather is nice.

 

[Missouri Mule]

I hav mine adjustes every fourth oill change. 24,000 as Factorry Servce Manual recommends.



Check exhasut manifold/gasket and make sure the down pipe hasn't loosened up.



Mine makes more noise in our cold weather here in the sunny south.

 

[38flathead]

Thanks to all who sent well-detailed postings - I have adjusted my valves, all vlaves checked out unfortunately I still have ticking perhaps it is the injector pump - any suggestions

 

[GaryOwen]

I would probably try some fuel additive and see if that helps.



Might be able to narrow down the source of ticking by using a large rubber hose to one ear and pointing it at different engine areas.

 

[Hammer]

I try and do mine at least once a year right before show/dyno season starts.



This way I am ensured that any high RPM twists with spray on the dyno do not have issues do to loose valves... ... ... ... Andy

 

[surfbeetle]

Maybe I missed it in your earlier posts that you were trying to get rid of a ticking noise, the most likely issue is your lift pump, not the valves. Mine has been ticking for years with no issues. As long as you have adequate fuel pressure from it to the P7100, you should be fine.

 

[Missouri Mule]

I had a tick coming from the p7100 once apparently a valve was sticking or a piece of dirt was in there. I put some cleaner/lube in the fuel tank which took care of the problem.

 

[38flathead]

Thanks for the reply funny you recommend fuel additive. I was comming back from a trip from tennessee to florida and Istopped at aflying j and bought some lucas additive and it just might be timing but when I got to altanta sitting in traffic with the window down is when I first noticed the sound ? the truck has been preforming flawlessly I don't know maybe it just one of those things that come with age? thanks for your addvice I'm open for more thoughts !