New Lifters..Runs Ruff ?
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From: MANDEVILLE, LA La
New Lifters..Runs Ruff ?
Put new lifters in the 84' (87' Block) runs real ruff..I didn't bleed them..I did adjust them by the book..can this be the problem?..some not closing properly?
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From: MANDEVILLE, LA La
Originally Posted by Great White North
Could you have one a bit tight?Maybe a wire mixed?If it was out of time when you adjusted it would be easy to get a tight one.
Safety Car
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From: FL
Originally Posted by Great White North
Could you have one a bit tight?Maybe a wire mixed?If it was out of time when you adjusted it would be easy to get a tight one.
Burning Brakes
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From: Langley B.C.
The early hydraulics used to recomend priming(Im old)but I have never primed any that I have done recently,just prelubed the outside and have never had a problem.I set them 1/2 turn past zero lash. Someone with a more profesional opinion will chime in!!!
Last edited by Great White North; Aug 23, 2006 at 06:23 PM.
Team Owner
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From: Summerland B.C. Canada
Originally Posted by toptechx6
I'd definitely agree that a rocker adjusted too tight or a crossed wire would make it run rough Great White but you lost me on the part about it being out of time when doing the adjustment, can you explain? Thanks in advance for the education. (not trying to hijack Cajun, just hoping to learn sorry)
It does sound like a poor adjustment. Don't worry about the lifter being full of oil. Loosen the rocker, wait a minute or 2 to allow the plunger in lifter to return to the top. The spring inside the lifter will push it back to the top of it's travel, then re adjust, being sure lifter is on the heel of the cam lobe.
Burning Brakes
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From: Langley B.C.
Originally Posted by toptechx6
I'd definitely agree that a rocker adjusted too tight or a crossed wire would make it run rough Great White but you lost me on the part about it being out of time when doing the adjustment, can you explain? Thanks in advance for the education. (not trying to hijack Cajun, just hoping to learn sorry)
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Thread Starter
Safety Car
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From: MANDEVILLE, LA La
Originally Posted by Great White North
The early hydraulics used to recomend priming(Im old)but I have never primed any that I have done recently,just prelubed the outside and have never had a problem.I set them 1/2 turn past zero lash,some guys set them at 1/4. Someone with a more profesional opinion will chime in!!!
Le Mans Master
Joined: Jan 2002
Posts: 9,036
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From: Edmonton AB
'87 block in an '84. Flat or roller lifters ?
If flat, have you read the threads about flat tappets and
modern oil additive packages. A reduction in the ZDDP additive
is attributed as the cause of early lobe failure.
.
If flat, have you read the threads about flat tappets and
modern oil additive packages. A reduction in the ZDDP additive
is attributed as the cause of early lobe failure.
.
Thread Starter
Safety Car
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From: MANDEVILLE, LA La
Originally Posted by Slalom4me
'87 block in an '84. Flat or roller lifters ?
If flat, have you read the threads about flat tappets and
modern oil additive packages. A reduction in the ZDDP additive
is attributed as the cause of early lobe failure.
.
If flat, have you read the threads about flat tappets and
modern oil additive packages. A reduction in the ZDDP additive
is attributed as the cause of early lobe failure.
.
Race Director
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From: The Top of Utah
One turn isn't too much. I prefer less, but that will have no effect on how it idles and runs, 99.44% of the time. The single biggest problem people have when adjusting the preload in hydraulic lifters, is missing or misjudging the point of zero lash, on at least a few lifters. Many people determine that zero lash is at a point that is truly beyond the real zero lash, and add the preload from there. That can lead to an over tightened valve that can never fully close. The other problem, much less prevalent, is not first, getting the lifter on the base circle of the lobe. Taken alone, being off the base circle, will lead to an adjustment that is too loose and noisy. Combined with missing the proper point of zero lash... anything can happen.
RACE ON!!!
RACE ON!!!
Melting Slicks
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From: Chesapeake Va
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
lifter adjustment
Another method is to bump the motor over and 1 cyl at a time make sure the intake valve has closed, then give it just another little bump to make sure both lifters are on the base circle of the cam. Then very carefully adjust each rocker while trying to move the pushrod up and down with your fore finger and thumb. When you can no longer move the pushrod up and down thats zero lash. Give the adjuster nut another 1/4 turn and lock it down. This is important: when you are done count the threads left in the adjuster nuts. If your adjustment is right then all of the thread counts will be nearly identical. I have went to the extreme of measuring them with a set of calipers and found that they are usually within .005 of each other. This has worked for me for decades. Hope this helps!!
PS looking at the head the valve layout is E-I-I-E-E-I-I-E
PS looking at the head the valve layout is E-I-I-E-E-I-I-E
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From: MANDEVILLE, LA La
Lifter Adjustment from Hell
Originally Posted by CAJUN C4
Put new lifters in the 84' (87' Block) runs real ruff..I didn't bleed them..I did adjust them by the book..can this be the problem?..some not closing properly?
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From: MANDEVILLE, LA La
Originally Posted by Pete K
Some books say 1 turn past zero lash(on base circle), some even say 2 or 2 1/2 past. 1 is not too much. Most adjust them in the area of 1 turn.
Melting Slicks
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From: Chesapeake Va
Originally Posted by CAJUN C4
Problem Solved..This procedure is for new lifters that don't have any oil in them.For used ones you must adjust them to zero lash and leave them. Otherwise the oil that's allready in them (pumped up) will leave the valves off the seat ..Adjust to zero and they will automatically pump out any unrequired oil after run time..Cancelled my Jegs order.
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From: MANDEVILLE, LA La
Originally Posted by edcmat-l1
Are you sure these arent solids? Even if they are already pumped up with oil, if you give them a 1/4 turn past zero lash they should bleed down and basically self-adjust. if they hold the valves open with just a little preload, somethin aint right. You either got them adjusted all the way down (plunger bottomed out inside the lifter) or they are solids.
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From: MANDEVILLE, LA La
Originally Posted by Pete K
Some books say 1 turn past zero lash(on base circle), some even say 2 or 2 1/2 past. 1 is not too much. Most adjust them in the area of 1 turn.
You have a PM.