Engine/Transmission (1998.5 - 2002) First 24V Adjustment Complete

[Alan Reagan]

Just finished adjusting the valves on my '01 at 105,000. Getting the valve cover off was fun because of the rear bolt. If you can get the bolts out, it will slip right out. Don't put the bolts in until the cover is back in place.



Hardest thing was barring the engine to TDC. I finally used the 15mm damper bolt so that I could see the mark while turning the engine. I found that a small pull bar on the ratchet makes turning the engine a lot easier.



All of the valve clearances were too high. I had to tighten every one of them to get them back to the the recommended reset clearance.



Total time for the job was about 1. 5 hours because it took so long to figure out how I could turn the engine and watch the marks.

 

[Big-D]

Alan,



Which valves did you find were the most out of tolerance? Exhuast or Intake?

Dave

 

[TKilgore]

Alan,

How for out of adjustment were they and were all cylinders fairly consistant?



Could you tell a difference in performance after adjustment?



Thanks



Tom

 

[Alan Reagan]

TKilgore and Big D, The exhaust were the most out. The intakes were only . 002-3 out. That's within tolerance but still I went back to the reset value of . 010. The most out were the number 1 and 4 cylinders. #6 was the closest to the reset value with only a minor adjustment required.



Could I tell a difference? Yes. I can't believe that minor adjustments make that much difference. For instance, clutch spring rattle has always been present in this truck starting off in second gear. The only time it doesn't have it is right after I change the oil. Since the valve adjustment, it is almost completely gone. That means to me that the engine is operating smoother and picking up load easier. I just went and refueled, stopped at Wally World, the drugstore and the bank so I had plenty of opportunity to start from a dead stop. Only heard it once, starting on an incline.



Also, the engine seems smoother and has it's old pep back. I wouldn't have believed the adjustment would have made such a subtle difference in performance but it did.



I'm headed back to Savannah this afternoon and will let you know if there is any mpg change.

 

[DavidC]

I did a check of mine a couple weeks ago with 48000 on the odometer. 1 exhaust below spec (tight) 1 intake above spec (loose). The tach always had a slight bounce at idle and now that is gone. That last cover bolt is a pain in the a**. I wound up holding the bolt up and slipping the valve cover over the heater hose on the pass. side to get the cover off. I would suggest if you have some free time this would be a good area to spend it on if your near 50k or over.



Dave

 

[TKilgore]

Thanks Alan,



Dave, that answered my next question. I believe the book says 100k to adjust. wondered if it would be worth while to do earlier. sounds like it might be.



Also another question,

Is there a relationship of working the motor harder more often (like heavy towing) with an earlier need for valve adjustment?



Thanks

Tom

 

[klaybus]

I was told the 1st valve adjustment was at 150k miles. I guess it's time to start thinking about getting them adjusted. I'm at 130k.



Clay

 

[Alan Reagan]

Originally posted by TKilgore

Thanks Alan,



Dave, that answered my next question. I believe the book says 100k to adjust. wondered if it would be worth while to do earlier. sounds like it might be.



Also another question,

Is there a relationship of working the motor harder more often (like heavy towing) with an earlier need for valve adjustment?



Thanks

Tom

Don't know the answer to that but I doubt there would be there's any correlation between heavy towing and the adjustment.



That last bolt in the cover is a PITA. I put it back in after I reinstalled the cover and that made it a lot easier do reinstall. As a matter of fact, I did the "over the heater hose" method and still couldn't get it on with the last bolt in . Kept hanging on the rockers. Once I pulled the bolts, the cover went right on and the bolts went right in.

 

[DavidC]

Originally posted by TKilgore

Thanks Alan,



Dave, that answered my next question. I believe the book says 100k to adjust. wondered if it would be worth while to do earlier. sounds like it might be.



Also another question,

Is there a relationship of working the motor harder more often (like heavy towing) with an earlier need for valve adjustment?



Thanks

Tom

I would think with higher revs the valve train would require more attention. I do not know if my system was like this from the factory or not. If not the only reason I can think of for a tight valve is the valve pounding the seat which then would require a factory installed height of the valve with a caliper guage to see if the valve is indeed pounding out the seat. The loose valve if not from the factory could show cam,rocker,push rod wear. I did not check any of this as I decided to adjust with in specs and check again in about 25k to see what happens.



Dave

 

[RRFinch]

I noticed your comment about "clutch spring rattle" in a previous post. Can you explain more about what you mean? I am having trouble with my clutch "grabbing" in first gear when starting a heavy load, but only after some miles and everything is "hot". Engine is basically stock - not real performance enhancements. If I keep rpm above 1900 the problem seems to be reduced. I have been thinking it might be slipping the clutch some below 1900. Do you have any thoughts?



Rob

 

[Alan Reagan]

Sounds like you may be slipping the clutch a little if it is grabbing. Mine doesn't grab at all.



The spring rattle has been there since it was new. If I give it just a touch of throttle it doesn't do it at all. It's only under load, starting off in 2nd gear with no throttle or just idleing in second or third if it comes under load, the springs give off a deep rattle.

 

[ben_ak]

Matco makes a special tool for rotating a Cummins for servicing (P/N MST9565A MSRP $44. 05 www.matcotools.com), I have one. It might make life easier for someone who wants to adjust their own valves.



-Ben

 

[Supermod56]

It's a good idea to check the valves, they probably have some slop due to the cam/lifter break-in. Mine has 80K, and I will do them when I put that cool valve cover from Bob Wagner on it. We'll see how bad they are!!

Tom

 

[Alan Reagan]

On rotating the engine, I have a barring tool. Problem is seeing the timing marks when using it. I ended up getting on the crankshaft damper bolt so that I could turn the engine while watching the marks. It's tight around the fan doing it that way but it worked good for me.



I can't remember the size of the nut..... sorry. I know some have used the alternator nut but mine would slip the belt and not turn the crank. Too much compression.

 

[Ol'TrailDog]

This is one thing I don't miss about my ol' 12v - valves every 24K Contortions to set the KDP at TDC were a real PIA. The barring tool is a gem however.

 

[Supermod56]

I think I will take the injectors out when I do mine, gonna change them anyway, it should make it a lot easier! On the race motor we do the intakes right when the exhaust valve starts to open, then the exhaust as the intake starts coming back up from the fully open position. Don't know if this method will work on the Cummins, we'll see



Tom

 

[JaMan]

Where can I find the tollerances and the instructions on how to adjust the valves? The valve cover is no biggie after you have done a few injector installs...



Thanks Jared

 

[Supermod56]

Geno's has the Dodge service manuals for a decent price, all the info is in there. Better to use a Factory manual than the other ones



Tom

 

[ToolManTimTaylor]

Factory manuals are gospel and prety much should be the first thing ya buy for the truck IMHO. Heck mine stay IN the truck.

 

[Wiredawg]

Cummins Makes 2d Gen Top-End Tune-up Kit

A few years ago, I bought a Cummins top-end tune-up tool kit for around $40. It has the barring tool, long handle swivel head ratchet, extention, all needed sockets, feeler gauge and oil filter wrench. Includes instructions too!



All high quality and everything you need.



I would not recommending removing injectors to perform valve lash adjustment. With the proper tools, the valve lash adjustment is easy and straight-forward, IMHO.



Wiredawg