Adjustable Rocker Arm Help....

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idrift

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I have crane gold rockers on my car and need a little help with the adjustment.

According to Edelbrock, I need to go to zero end play then turn the
adjuster 1/4 turn and lock them down. Ok all fine and good. These
are hydraulic lifters so I could probably get by with a half turn or so
right? Here's my problem. I adjust to between 1/4 and max of 1/2 after
I have no end play BUT after the end play of the pushrod is taken up
I can still compress the lifter plunger down say almost .100" is that
normal? I am doing this with the engine quite hot. Would the oil pressure
when it's running take out that endplay or am I having some lifter go bad?

I have some valve clatter so that is why I am adjusting them slightly more
than the 1/4 turn but thought I look for experienced advice while I have
it apart.

She clatters hard on startup but after it is warmed up it's better and if
I don't let her sit for a week without driving it's also better.

The pictures show how much I can compress the lifter plunger by hand
after the preload is set to 1/4-1/2 turn.

Thanks,

Doug

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idrift said:
Bump....
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Something's not right here, you should not be able to compress the lifter piston simply by using your hand and pushing down on the push rod end of the rocker, If this is what you're doing. The lifter should have hydraulically locked therefore the lifter is faulty and should be removed, disassembled and cleaned. Probably a piece of dirt. Also did you make sure that you were at TDC, beginning of power stroke when you set the valves on the cylinders, there is also a chart you can follow with a sequence you can use every 90 deg of crank rotation. BTW you should be able to compress the lifter piston, approx. 100-130 thou. but only when completely dry of oil.

Terry
 
When you push down on the rockers I am assuming the piston is all the way top of the bore with both valve closed. Mine had play like you are describing but when I pushed down on mine the motor was cold. What I believe is happening is putting pressure on the rocker arms pushes the push rod therefore pushing down on the lifter spring which is normal. Sounds like you are ok to me IF you adjusted them correctly.
 
all hyd. lifters run anywhere from about .020 to .060 preload. 1/4 turn is on the low side about .020 so 1/2 turn sets you about .040, I set all mine to .040 to start and most every time no more adjustment is needed. as far as the lifter plunger still having play i wouldn't worry about it. when you shut the motor off if there is still pressure (like the valve part way open) on the plunger then it is already starting to bleed the oil out of the lifter. the pump pressurizing the oil through the body is what pumps it up, plus there is alot of play in the lifter besides the preload. most can take up to .090 or a .10.
 
Sorry guys but I've gotto disagree. Doug did say that the engine was hot when he performed the check and the lifters should still be pumped up and hydraulically locked at that point. He also mentioned that the engine clatters pretty bad when he starts it after it's been down for a week or more, this also tells me he's got 1 or more lazy lifters.

Terry
 
Even if you can push a lifter down when the engine is hot really doesn't mean much. When the engine starts and the oil pressure comes up those lifters will be hard as a rock. The lifters are just bleeding down. They probably have some time on them. Worth changing? It might clear up the clatter, but new lifters might also wipe out an old camshaft too. Its a gamble either way. Maybe change the cam and lifters.
 
Demon seed is right and the eng. oil pressure just feed oil to the hyd lifter and does make the value open the lifter traps the oil then pushes the push rod up now that being said the lifter will do what it is doing if it is a high bleed lifter i think they are roash or very high spring pressure
 
simple test of just tightening them down to 1/2 turn and see what happens. if it stops the clattering your fine, if not you know you have a bunk lifter.
 
camd64 said:
simple test of just tightening them down to 1/2 turn and see what happens. if it stops the clattering your fine, if not you know you have a bunk lifter.
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I have always went 1/4 turn and I have some clatter when the motor is at or above running temperature. I believe you just convinced me to go 1/2 turn.
 
I followed the adjusting sequence provided in the cam kit from eddelbrock so
I think they are adjusted right, since I posted I tightened them up closer to
a half turn and they sounds quieter but I need to let it sit overnight an then
start it up cold.

The car sat for quite a few years I understand so I am starting to wonder if
I have some lifters that are going bad. Like mentioned above I'd hate to
break in a new set for fear of wiping lobes. I'll keep you guys posted on how
she sounds cold. Thanks for all the replies.
 
I agree with demonseed. Lifters should not bleed down like that and be so spongy you can push them down by hand. And they shouldn't clatter when you start it up either. 3 yrs. ago when I first rebuilt my 360 I put a Comp XE274 in it and had the same problem. After 150 miles 3 of the lifters decided not to pump up anymore at all so I took it apart and called comp and they sent me a replacement set under warranty. They worked great for the first 500 miles then started bleeding down after it sat and you could push down on the lifter right after it was ran. Another 100 miles and 2 of them would no longer pump up. That got old real fast. I pulled the Comp set out and put in a Lunati 60404 cam and lifters and haven't had one minutes worth of clattering out them in nearly 4,000 miles. You can't push them down after it was ran either.
 
ya but clattering can be wrong size pushrods also. I had the magnum conversion with the blocked decked
 
but if it was bad lifters it would do it all the time...no?
 
When they first start getting sloppy they can do what he described. As they wear more they may do it all the time as I mentioned in my first post of how mine did.
 
Well, I have to think it's some of the lifters going bad. The car did sit for
like 5 years I was told so I'm sure that didn't help a new motor at all.

I have them adjusted a little tighter and it seems quieter, but as mentioned
I"ll see what that does for me in a few days. Might be time for a new set up
shortly. I'd really like to get this season out of her though!
 
First, I don't feel the Edelbrock lifters are really good. They have that flat metal retainer instead of a round wire clip on the plunger and that retainer will pop out over time. Last one I took apart had 6 of 16 like that and the engine was running with no noise. You can usually find them hanging around the lifter end of the pushrod. They are no more than a stock non-performance lifter so it does not surprise me that they can be comressed that far. IMO, they should not be able to. However, another thought is the lifter bores. Were they measured? I run a max of .002" clearance. If they are larger than .906" ID it's time to bush them. That has only happened once in the 40 or so I've done after starting to check. But it does happen.
 
moper said:
First, I don't feel the Edelbrock lifters are really good. They have that flat metal retainer instead of a round wire clip on the plunger and that retainer will pop out over time. Last one I took apart had 6 of 16 like that and the engine was running with no noise. You can usually find them hanging around the lifter end of the pushrod. They are no more than a stock non-performance lifter so it does not surprise me that they can be comressed that far. IMO, they should not be able to. However, another thought is the lifter bores. Were they measured? I run a max of .002" clearance. If they are larger than .906" ID it's time to bush them. That has only happened once in the 40 or so I've done after starting to check. But it does happen.
Click to expand...

Thats not what I wanted to hear, but very good advice. Thanks.
I will take a look inside and see if I can see anything.
Perhaps I should put a new cam in the budget, or a better set of lifters.
 
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