The Stovebolt Site Forums The Shop Area Engine Shop valve adjustment

When and how should I adjust my valves in my newly rebuilt 235. The factory manual say to normalize the engine and then adjust the valves static.

My rebuilder said to do them with the engine running. Back off each rocker until it clacks and then tighten it until it stops clacking then give 1/4 turn

Which is better?

Also should I drive the truck a while before adjusting them? It runs great now but the engine has literally about 1 hour on it since the rebuild.

Should I drive this a few miles/ hours before I re adjust valves, timing, idle, fuel mix?

Thanks
RB53

You can't adjust your valves too often. If it has run an hour, it wouldn't hurt to check them and again in a thousand miles. I always adjust valves with a feeler gauge while running at a slow idle.

When I was much younger, I adjusted valves with the engine running (that was how I was taught).

For the past 15 years, I have been using this "static" procedure.

As stated in the instructions at the link above:

1. Make sure that each rocker arm surface that mates with the top of the valve stem is smooth. Grind smooth and polish, if necessary.

2. Warm up engine to a stable temperature and then run the engine for 30 minutes (this is important).

3. Stop the engine.

Tim

I have that sheet of instructions does the fact that they installed a hydraulic cam and lifters matter on the method?

Rich

Rich,

Yes, adjusting hydraulic lifters is a different technique.

http://chevy.oldcarmanualproject.com/shop/1955/55csm0612.html

Wait to hear from some one who has done this.

Are you sure its hydralic tappets?

That's what he told me
New cam
New hydraulic lifters
New pushrods
Among many other new parts

I just assumed you had solid lifters. If you do indeed have hydraulic lifters, it would be helpful to state what you have in the first place. If you read a factory manual for a truck, would would be reading instructions for solid lifters.

Rich,

Didn't you post in an earlier thread that the engine serial number ended in 54XA - 3600 truck 235? All 235 truck engine came with solid/mechanical lifters.

Did you ask the rebuilder to put in hydraulic lifters (or, had someone already converted to hydraulic lifters)?

Call the builder for a confirmation of what style lifers he used.

Good luck - you'll get this engine purring soon.

Tim, thanks for the valve setting guide! I copied it to a text document for my near future procedure!
Wouldn't RB53 be able to pull the side cover and see the lifters are hydraulic or solid?

Jerry

If they are hydraulics, I would adjust them as your mechanic said. I like to go beyond the final setting to make sure that the lifters aren't sticking. If it were a quarter turn, I would go to half and then back off to a quarter.

Jerry,

Yes, but the hydraulic lifters are sometimes hard to identify until you pull one. Calling the rebuilder would most likely be the easiest way to get an answer.

A quick way to tell is to adjust zero lash on one or two of them and then give it another turn. If its a solid lifter, it will create a miss, our you can disconnect the coil wire and turn it over, you can hear it blowing in the manifold. If its a hydraulic lifter, it will compensate for it. There are are machine shops today that have guys working there who can machine things to spec, but have no clue that mechanical lifters even exist.

Is this a 54XA block we're talking about? If so it wouldn't be drilled for hydraulic lifters, they won't be getting any oil, unless extensive block modifications were also done! The question of hydraulic or solid lifters needs to be answered before running this engine IMHO.

If you look at my original post. the instructions I have are from the builder.

He told me the procedure for adjusting them but I have only seen documented the static way of doing it wether solid or hydraulic.

He said he put hydraulic lifters and new rods and a cam. He did all the block machining and I have driven the truck several times for several miles now and no problems...there seems to be oil getting everywhere it needs to.

I think I will follow his instructions. As long as i don't over tighten them it can't do any permanent harm...can it.

Rich

I would think if there were no oil getting up there i woudl have serious trouble already.

The rocker arms feed through a special head bolt and passage way through the block. The lifters get oil differently.

Might double check the numbers on the block to make sure your block is indeed bored for hydraulic lifters.

Hmmm...I know the block number is correct. This was rebuilt by a very experienced builder. He does a lot of older engines.

I did not ask for hydraulic lifters but the cam needed to be replaced and he told me he put hydraulic lifters in.

It is possible that he drilled the block for the hydraulics... I paid enough money
It is also possible he made a mistake. The engine has a 1 year unlimited mileage warrantee on all parts and labor.

How long would the engine last if the lifters were not getting oil? Would it be a very short high RPM ride?

What are the symptoms of no oil on the lifters. I would think the engine would not run but other than a few minor issues this one runs good and sounds good.

Any thoughts on these questions. I will call the builder tomorrow.

Rich

I don't think it would even run with hydraulics and no oil pressure to them, unless the lfters were compressed all the way down inside. Hydraulic lifters need constant pressure to operate.

I talked to the guy today and he said they are definitely hydraulic lifters and he said he does this all the time. The lifters are quiet (much quieter than the old solid lifters in my 216).

I set the timing by vacuum tonight and it ran much better but the timing by light was fairly advanced. (out past the C on my flywheel) It ran and had more power and less surging. Is that too far advanced. I got very little ping at high RPMs.

I am still having some issue with power and surging. Which could be a vacuum leak. I do hear a puffing noise but can't find it. My vacuum is only at 16. Wouldn't a vacuum leak be constant hiss if you could hear it?

I am wondering if this has anything to do with my head gasket issue. I noticed tonight after driving it there were a few areas along the head with some small bubbles again.

I seem to be going in reverse

Rich