valve lash question

[AdamG]

Sorry this will be my last question for a while. we are going to pull the car into the garage this weekend and try and get everything operating RIGHT.

I still think my valve adjustment is off I am getting a lot of chatter. I am now thinking I over adjusted one of the lifters. I bought polylocks to make the adjustments right this time. But now if i over adjusted it will it pump back up on its own? should i loosen the rockers a little and let it run so they pump up? should i pull the intake and inspect all the lifters?

[95ImpySS]

Easyest way to to do it is by the book. Engine off, #1 at TDC and go in order. with Poly locks you should only use about 1/2 a turn of pre load. http://shbox.com/1/4th_gen_tech2.html#adjust_valves
Did you do it the way stated in the link above?

You can adjust with the engine running and valve covers off. But that method is not a precise and makes a mess.

Chatter would mean that the rockers are loose. If you can run the engine with the valve covers off, CAREFULLY push on each rocker (on the back where the push rod is) and listen for a change in the clicking. If it gets quieter then that rocker is loose. Slowly tighten the nut until the clicking stops, then 1/4 -1/2 turn more. Repeat for the remaining loose rockers.

[AdamG]

I did it the way shbox.com way with the engine off. I didnt feel confident that i did them right so I had a local shop do them again but after that the car did run right. few weeks ago we heard a tick and i tried to adjust it while it was running and got the tick to go away but it still doesn't run right and the tick is now back.

I plan to use the method of the engine off this time. Im just not sure how to figure out when 1 is in top dead center since i pullet the crank hub off and im not sure i put it on the same way


Edit when the 1 cycinder valve intake opens then exhaust opens and closes that means 1# is at top dead center should i adjust all valves int that sequence and do the same for cylinder 6?

or should i rotate for intake to open close then exhaust then go a quater turn and do the same for each cylinder?

[Tony Shepherd]

You can adjust with the engine running and valve covers off. But that method is not a precise and makes a mess.

.


I dis-agree with you. It is actually more precise when setting them with engine running. For a hydraulic setup, setting them first dry from the book gets them close. After that set them with the engine running (idling) gets them exact. You do this by sound and feel. With engine running, back the nut off until the rocker starts clapping, then slowly tighten until the clapping goes away, then tighten 1/4 turn more. Tighten the poly and your done. Move to the next one.

You can also feel when the lash goes away when you are turning the nut.

[95ImpySS]

I see what you mean Tony. I always figured taking your time, feeling out the push rod for bind then tightening it down would be best. I guess that since the lifters are not pumped up with oil, there is a chance that they are not fully up at their limit. Rather than assuming that the spring has pushed the plunger up you are guaranteed that its pumped up since the engine is running.

AdamG I don't trust shops one bit. Take your time, do it by the book and then take it a step further and do it with the engine on. To get number one to TDC , pull number one spark plug. Watch the rockers wile spinning the crank clockwise. Watch for the intake rocker to push the intake valve down, then watch the rocker come back up. When it stops moving, stop turning the crank. Get a wire clothes hanger or some other stiff item that you can stick into the cyl and feel the piston. DO NOT DROP IT IN THE ENGINE. (Should be common sense but you never know ;) )Slowly spin the engine feeling for the piston to stop. Once the piston stops moving up. Your at TDC.

[Tony Shepherd]

I see what you mean Tony. I always figured taking your time, feeling out the push rod for bind then tightening it down would be best. I guess that since the lifters are not pumped up with oil, there is a chance that they are not fully up at their limit. Rather than assuming that the spring has pushed the plunger up you are guaranteed that its pumped up since the engine is running.

.

Exactly. They will be pumped up. You are setting them in real-time pressures and load.

[AdamG]

okay so the consensus is do the final adjustment While its running? I have a extra set of stock valve covers should i cut them up to make a splash shield out of?

[Tony Shepherd]

okay so the consensus is do the final adjustment While its running? I have a extra set of stock valve covers should i cut them up to make a splash shield out of?


Yes.

Cutting a pair of stock covers are a great idea. I usually place a cardboard backsplash below the valve cover surface of the heads. Oil hits it and rolls down. For the most part the oil will not spray everywhere if you keep it a idle.

[Flyinz]

Good tips Tony. I've heard that technique from most of the "old school" guys around here. I guess I never thought about that, working on LT1's...Its basically the same HR system.

[AdamG]

Hey guys i was thinking about it again last night and im thinking this isnt a valve adjustment issue. I think i have a bad lifter. Every time we adjust the valves its good for a short time and then it starts making more and more noise. when I started the car up this morning to pull it into the garage it was making a ton of noise. but slowly quieted down. I bought the lifters at napa and they are seal power lifters I thought they would be alright because this is a mild build car.

I figured i would replace the lifters in the car now with these ls7 lifters http://www.ws6project.com/user_stor/catalog/gm-performance-ls7-lifters/ . its 150 bucks for the lifters and gaskets and cheap insurance in my mind.

what do you guys think?

[Fastbird]

Just don't do the engine running method with Comp R lifters. Learned that one the hard way. The thin metal upper cap retainers on the lifters (not the wire retainers you normally see) will come spare and crap your lifter out.

Sent from my factory refurb but way better than my first HTC Rezound

[Spartan7]

Make sure you don't have a bent pushrod before you spend the money on lifters. But if you doubt the lifters, they're not that expensive or hard to replace, good peace of mind. The LS7 lifters is what I use.

[TSAEB]

Not sure if it's enough to make a change But the inside plunger on the ls7 is about .05 higher then the oem lt1 . Again don't know if thats enough to affect anything . And the ls7 lifter is now the oem replacement for lt1 motor if im not mistaken . Last summit , jegs or Herron performance can sell you those lifters for around 135 shipped.

[AdamG]

i ordered them 129 shipped . I honestly dont trust the lifters. A few years ago i bought a chevy lumina with a "bad Lifter" I got it home started it up for 30 seconds and the engine shut right down the damn lifter jammed right in the block. I will check the valve train geometry before start up to make sure i don't need new push rods. So the age old question should I soak them or not soak them before install. I did last time and part of me says i should this time but on other rebuilds i haven't. But i have read stuff going both ways.

i had the covers off and check the rockers and pushrods 2-3 weeks ago and they all looked in good shape then. But i will definitely check them again.


I order everything I can from the ws6store. I screwed up a few years ago on a part that was a nonreturnable part I bought. i opened it and realized it was wrong. I called them up and and asked to order a new one over the phone to make sure that I got the right part and they asked me why I was buying a 2nd one And I explained I accidentally bought the wrong part and on their own they made the whole thing right. After that I am a die hard customer.


By the way this isnt normally how I like to work. But as of right now I am borrowing a friends garage for the next week and a half. I need to have as little down time on ordering parts to get the job done. So taking them out and inspecting them and waiting for shipping kinda isnt an option.

[95ImpySS]

Might as well go new. LS7's are pretty good. I have had mixed luck. But many run them with no problems. I always soak mine. A buddy decided to pull his apart and check them out. They all were full of a very light weight oil. So soaking them prolly only lubricates the bearing in the roller portion. Change em out. check your push rods. Make sure you note which way they came out so they go back in the same way. Make sure you get the intake sealed good. Mainly in the rear. I always use a healthy amount of black RTV. Then test fit the intake making sure the RTV seals all the way around. Then I bolt the intake down. FWIW I found that buying LS7 lifters from the dealer was the cheapest route. Under $100 for a set of 16.