Engine/Transmission (1998.5 - 2002) Valve Adjustment

[csevers]

I just adjusted the valve for the first time at 93k last Saturday just to see how far out they were and to see what changes it would make to how the truck ran. The 99 manual has the Intake "range" from . 006 to . 015 and the Exhaust from . 015 to . 030 . I checked all of them before adjusting them none were out side of the "range" but most were very near the top end so I adjusted the I to . 010 and the E to . 017 the book says . 010 I and . 020 E . I could be crazy but the truck runs way stronger and quieter for sure. The manual says there is no performance or economy noise benefit to be had with the valves in the "range", maybe for a stock truck but if pushing more air and fuel it must make some difference. Has anyone else noticed a better running truck after valve adjustment? Has any one dynoed before and after valve adjustment on a bombed truck? It really runs noticeably better!!



Craig

 

[ROADWARRIOR]

Craig,



I adjusted mine and thought that there was a slight change in sound and performance. Could've been my imagination, don't know.



Dan

 

[LSMITH]

Craig and Dan, I have been talking about this for 2 years. IT HELPS!!!!!!!! I have played with settings all over the map and found with my combo . 007 and . 016 is the right spot, it frees up the top end tremendously. . 012 and . 025 has great low end if that is your bag... ... .

 

[crawler]

Instructions Please.

Would somebody mind posting on how to do the valve adjustments.



Thanks,

Wes Snow

 

[Heavy Metal]

Just having hit 100k recently, I took mine in this morning for valve adjustment. I just considered this another maintenence item until I drove off. Definately runs & sounds better. Sounds stronger at idle too.

 

[csevers]

I can type it out it will be long but here it goes

First you have to have the tools like feeler gauges and basic metric sockets, sizes of feeler gauges is in the first post I think 15mm is the size for the valve cover and the front bolts on the crank (that is how I turn over engine ) So to start remove valve cover then remove round plug ahead of the vp-44 IT IS threaded in to the front tin cover looking at it turn it counter clockwise you first have to remove the breather hose if a 24v. Notice the marks on the gear in side the hole were the plug came out there is a mark the is Top Dead Center for #1 cylinder when this line it straight up the engine is on TDC #1 when straight down TDC #6 you can start either point depending on witch is closer to were you are starting I started on #1 because it was only a have of an engine rotation a way turn the engine over either with the "proper" baring tool or by way of the front crank bolts only go one way so not to loosen the bolts line up the line on the pump gear straight up and then you can check or adjust both intake and exhaust on #1 cylinder then check or adjust Intake on #2 Exhaust on #3 Intake on#4 Exhaust on #5 leave #6 alone Then rotate engine over till the line on the pump gear is straight down Then you will start in back with both valves on #6 Intake and Exhaust then Intake on #5 Exhaust on #4 then Intake #3 and Exhaust on #2 now all the valves have been checked or adjusted. Most people use the "feel" method of adjusting valves so there is a slight drag on the feeler gauge between the bridge and the rocker arm. I don't have the spec for torqueing the rocker arm nuts make sure they are tight. Reinstall the valve cover and the plug in front of the VP-44 and reinstll the breather hose start and run should be less valve clatter noise.



I may have missed a step I am not a column writer, If I have missed something feel free to add If you have never adjusted any valves on any thing I would take it to a mechanic or have some one that has done valve adjustments lookin over your shoulder you deffinatly want it done right the first time!!



GOOD LUCK

Craig



P. S. I told you it was gonna be long

 

[DEZLPWR]

well done

Seems to resemble the instructions found in my service manual... Nice job!

 

[LSMITH]

A search would have turned up pre-typed and ready to read instructions as well :-laf :-laf

 

[Rman]

I adjust the valves on my dirtbike 2 times a year, with 5 valves on one cylinder, having just one or two off really makes a difference in throttle response.



Do you adjust the cummins valves when warm, or do them all cold? Anyone ever owned a solid lifter v8 before... oh yeah valve adjusting is never ending process. It was a once a month ritual... always heard ticking! Had some power and throttle response though.

 

[ACoyle]

Some more info with pictures.

http://dodgeram.org/tech/dsl/valve_adj/12_valve.html

 

[crawler]

Search

I did use the search. But I just thought the short version would be beneficial to the people reading on that are unable to post. Thanks everybody.

 

[LSMITH]

The search does reveal the short version. It was written by Chad Sheets. You should have found it in nearly every post ever written about valve adjustments. Scroll down to the post by Whitmore. That is the simplest and easiest way to do it I have seen yet. It is the procedure that has been passed around here for a LONG time.



https://www.turbodieselregister.com...?s=&threadid=62849&highlight=valve+adjustment

 

[pwr2tow]

Well done csevers

 

[jmeehan]

Originally posted by LSMITH

. 012 and . 025 has great low end if that is your bag... ... .

So this would be better for off the line. I haven't heard any of the drag racers talking about valve adjustment. Is this just a well kept secret?

 

[A Johnson]

Adjusting screw jam nut torque is 18 ftlbs.



Having said that nobody hardly ever torques them, and they are easy to overtorque if you don't know what 18 feels like. They will take more torque but then the threads get buggered and the next time they are hard to adjust.



I like to set them so the feeler gauge snaps out, about 3-5 inch pounds on the adjusting screw before locking it works good.



A Johnson

 

[LSMITH]

Originally posted by 85CJ

Is this just a well kept secret?

No not really, just about every serious gearhead I have known has used it to make power in the spots it is wanted. On a forced air induction engine (ours) it changes cam timing with some small changes in overall flow. On naturally aspirated engines it can make a tremendous difference in overall driveability, you can essentially "take some cam away" or give it "more cam" easily.



If you were referring to the diesel drag racer crowd I am not sure if they do anything or not, with the massive boost and fuel they run there may not be any serious benefit.



Play with a few settings, each adjustment takes me less than 40 minutes working at a medium/easy pace. See what it does for you.

 

[mchelius]

Do you adjust the cummins valves when warm, or do them all cold?

 

[LSMITH]

Dead cold, a search would have revealed that as well