Adjust Valves at 24K?

[smartineau]

I was talking to a Cummins Northwest mechanic awhile back and he said that I should have the valves adjusted around 25-30,000 miles. I would get a better running motor and would increase mpg by at least 1 if not 2 mpg.



steve

 

[DPKetchum]

Was he thinking 12 valve or 24!

 

[Ladders]

Just to add to the confusion ...

On the y2k I had them adjusted at about 25k. The mech (and some others) said it would be "better" to adj a little loose. Supposed to give better power, mpg, etc. Didnt really notice any but hey it was a free-be under warranty. May do the same with the 03, just to ENSURE they were set correctly from the factory. Worth it if you can get it done under warranty (ie: lose of power, low mpg = maybe a valve adj??).



SOTSU!!

\\BF//

 

[DPKetchum]

Loose valves always give a better idle but thats NOT what the specs call for and the b59 Cummins have a nice idle anyway. Specs is specs and no need to deviate from that.

 

[RonWeiss]

Loose doesn't mean better idle... it actually means a little less power, BUT your valves will live alot longer.



The more time the valves spend seated, the cooler they will be and thus last longer.



If you tighten valves up (less clearance) they will allow for better breathing which means more power !! but too much and they will burn and get misfires.



At least that's what my dad told me



Ron W.

 

[y-knot]

If you guys want to have your valves adjusted, fine. You do not need anyones permission from this forum. Would I, yes. Did I, yes. Would anyone think "it seems like a good ideal"? Yes. Do you have to? Maybe not, my owners manual said it needs to be done, and I thought it was a good ideal. I felt better for doing it, it gave me a base line on where the engine was, and what it might need later. Is it hard? Well everyone can type how easy it is, but doing it is another thing. Yes, I have done valve adjustment on many , many gassers. I have built race engines, that lasted, and felt comfortable doing so. But that does not mean I should feel just as comfortable doing it to my diesel truck. I did not, so I went to a EXPERT, who did. Sure it cost money, but doesn't everything now days?? It is just another maintenance issue, I really don't care what anyone else does, I like to know,hear your opinion,your experiences, experiments, ect. But I do not loose any sleep at night, because someone didn't take there truck in for a valve adjustment, it won't happen. If they feel there way, good. it's like OIL, everyone has there favorite, and that is good, it keeps alot of people employed. With maintenance there are three groups. 1. guys that just don't do it, and could care less. 2. People that do it, just not all of it, or with in the time intervals recommended. 3. people that are religious about it,they might even look forward to it, and enjoy the time. Or just realize it needs to be done, and so it gets done. I am a 3, I love to do it, can't wait to change oil, filters,you name it. I also love to tinker, and try new things, that is just me. I also recognize that the world is made up of many different personalities, and I think that is great. So there is no right or wrong, just do what you are comfortable with.

 

[DPKetchum]

In your sig it says a 97 which is a 12 valve and it was a adjust at 24k then ever 48k. The 24 valve is not set up the same way. When I worked in a Datsun/Nissan dealer ALL the techs did valve adjusts daily. This day and age NOT many autos require a valve adjust,I know some GOOD techs who hadn't adjusted valves in any thing hardly EVER. I did my 93 W250 myself because I didn't know any experts anymore that had any real experience doing valve adjusts. I took my time and followed the book and MADE sure they were spot on. Took about 2 hours. But the 24 valve B59 dosen't require this until around 150k if I'm not mistaken. As far as changing oil I CAN"T stand doing that myself. Its kinda like cutting grass I do it cause I have to but looking froward to it NO WAY. Use to love tinkering with machinery but last decade its not tinkering its called REPAIRING. It not fun,its WORK.

 

[mchelius]

Use to love tinkering with machinery but last decade its not tinkering its called REPAIRING. It not fun,its WORK.

DPKetchum, Sounds like the Thrill Is Gone!!

 

[Briman]

Evan with a second mention - Ynot has not confirmed he is talking about his 97 that's in his sig or maybe he has a closet '03. If I had a twelve valve (and I have had 4 of them) I would (and have) follow the directions for them. If I had an early twenty-four valve (two of those) I would follow the directions for those. If the manual for the currant twenty-four valve says leave them alone, unless your under the valve cover for other reasons, leave them alone. Now, I do disagree with manufactures that say you don't need to change spark plugs for 100k miles so I suppose I can understand some people wanting to verify their valve lash, but for goodness sake - it does not need to be done at 25K miles. To have a dealer do service that is not called for is like asking for trouble (caused by the servicing mechanic). Most of us that do our own service can be better served by spending the time that it would take to verify valve lash by throwing a ball for the kids or dogs. Modern engines are built to much closer tolerances than in the past and if assembled correctly at the manufacturer valve lash should be optimal for a long period of use. I realize that there are manufacturing anomalies that create tolerance situations that are not optimal and need to be dealt with. Just my opinion, sorry for being long winded.

 

[Ladders]

I think that my post saying "loose" adjustment for the valves meant "out-of-specs" loose. It did not. With the tolerances give they were set to the "loose" side of the specs. If I had the info for the y2k, there was a wide range, the specs were quite "broad". Dont know if the 03 is the same or "closer" from tight to loose. But still, good discussion and some others thoughts about it are always welcome. Better for making own decisions based upon others experience(s).



Thanks for your thoughts... .





SOTSU!!

\\BF//



EDIT: just ckd spec on the 03: 9thous dif on the intake and 15 thous dif on the exhaust from "tight" to "loose". Still going to get mine chkd in case of factory "mis-set". At least I have a verified starting point for future reference. Just like the BOMBING, nice to start with a base line that you know and have figures for. Some of us dont use a baseline and if we are low in power to start, we dont really know what was the increase. If all the units were at the same base (which we know due to mfgr tolerances, etc, are not true) we would not have some of the differences that are posted from time to time. Would it not be better to have them all set to the same setting or have that much diff between them?



Just another opinion and its mine, but your welcome to use parts as you see fit.

 

[badams1]

To Deep creek

The Cummins dealer and service center in Houston is listed in the phone book. They are called Great Southwestern or something like that. They are located on 610 loop north east side near Wayside exit if I remember right. I go there often for filters, lift pumps before the 03 "he he" and stuff and they are first class just as you would expect them to be.

 

[DPelletier]

This IS a 3rd Gen forum, right? I guess the short answer is: your '03 does NOT require a 24,000 mi valve adjustment.

Dave

 

[XcumminsX]

all 24 valves need it done at 100,000 i read that in a tdr thing i got in the mail today

 

[Vaughn MacKenzie]

IMO . . .



1). If you're happy with how your rig runs and you're fine with your Cummins being "average" then don't bother with the valve adjustment until 100,000 miles.



2. ) If you prefer a well-tuned top performing machine, check them by 25,000 miles.



Like I said, I've seen valve lash on 24 valve trucks all over the place but still (barely) in spec at 60,000 miles, and some out-of-spec by that time. There's been quite a few posts in the past on this in the 2nd Gen 24-valve forum. It's not that tough to do if you're careful.

One important tip: any rocker you go to adjust, wiggle it first. If it's tight and you can't tap it up & down on the pushrod, then you've got the wrong one (or your engine's not in the right position) and therefore don't tweak it.



When properly adjusted, the proper-size feeler will barely go in and have some resistance when you slide it around. The next . 002" larger shouldn't slide in there. It's a little tricky on the Cummins with the actuator cups, you have to use one finger to tilt it a bit toward the feeler to let it slide in. And the other tricky part is tightening the nut without the adjuster shifting position.



It's not hard to get the feel for it. Luckily the first ones to adjust are both intake/exhaust on Cyl #1. Once you get the feel do the rest, and when you're finished with the last one come back to #1 again and recheck it to see if you've been consistent.



Vaughn

 

[curatchko]

OPINIONS OPINIONS!!!!



I love how everyong shoots off their opinions instead of the facts when someone asks the question.



READ THE MANUAL.



Valve lash adjustment on the 24 valve 3rd generation is at 135,000 miles.



Not 24, not 30, not 75, and not 100.



Lets stick to the facts.

 

[Macker]

valve

AMEN BROTHER!!!!!



IN MY OPINION, THATS ONE BAD 04'

 

[Vaughn MacKenzie]

IT's a fact 135,000 miles is stated in the manual.



It's a FACT, not opinion, that valve lash it out of spec by 50K sometimes.



Vaughn

 

[Swayse]

I did mine at 29,000 miles, most were a little loose, but 3 and 4 intake and exhaust were out the most. I'm glad I did mine.

 

[RonWeiss]

Swayse,



After the valve adjustment did you mtice any difference in power or sound at idle?



Ron W.

 

[Swayse]

I think it idles and runs smoother under power. I can't say for sure, it may just be pride in a job well done.