H all, the truck has 30,ooo kms [18000 miles] on it I'm the second owner 1st owner had it till 24000km[14500 miles]and towed fifth wheel ,for the next 3 months I'll be doing the same .Question: when should the valves have thier 1st adjustment? I'm changing out the oil and filters before I leave but was concerned . I don't trust the 'car' meck-antics at the dodge dealer and take it to the western star dealership and have the cummins mech do the work so do a lot of the other snowbirds WAY cheaper than DC. Anyway what's the word Thanks

 

I think the owners manual says every 100,000miles but personally would do every 50,000miles. These Cummins engines dont seem to change very much at all over a long duration. When I bought my truck it had 140,000miles on it and I know they were never adjusted, so I did and they werent out of spec at all.
carty

 

The word is 150,000 miles. I have heard people doing it sooner and getting a good kick from it. I have also heard the factory sets them a little loose.
Hope this helps.

 

Personally I feel a valve adj. is like kissing your wife(you should do it nobody else) Soooo adj your valves-bet they are real loose- not that will hurt anything but sure runs better snorqed up like they should be.
Most of us gear heads run them a thou tighter then the book says with no adverse results.
Here is some therum for ya - for every thou of slop there is that equals 2 thou crank revalution so that equals a hole lot of crank turnin with nothing happnin upstairs ( you loose lift and crank timing but get cooler valves)

 

What do you lash the valves to? I'm planning on doing mine soon.

 

From the Service Manual for a 2000.
Done with engine coolant temps less than 140 degf.
Intake 0.006 in min
0.015 in max

Exhaust 0.015 in. min.
0.030 in. max
I have heard it worked best with them on the tighter side.
This is also called running the rack.

 

Why is the intake tighter than the exhaust? I kinda figured that the number should be the same for the exhaust and intake. Thanks for the info.

 

Because under operating conditions the exhaust valve will get much hotter than the intake valve. Therefore it will get longer and reduce effective valve clearance. If you set the exhaust valve to the intake specs it will even stay open a bit when it should be closed and look like Kojacks lollypop within seconds.
(Kind of blowtorch effect)
AlpineRAM

 

I did mine at about 45,000. They were all within spec, but I tightened them down to the tightest tolerance. I'll do it again when it hits 100,000.

Mike