Hydraulic lifter adjustment

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OUTLAW

OUTLAW

Master of All Mopars
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I have never seen any adjustment figures for hydraulic lifters with adjustable rocker arms. By this I mean, after getting zero lash, how far do you preload the lifter? 1/2 turn ? 3/4? or 1 whole turn? I looked at every cam manufacturer, and their procedure , and not one says how far to preload them. Any suggestions? at 1/2 turn they are a little noisy and 3/4 to 1 turn doesn't seem to make any difference between these 2 settings.
 
They all give you the needed adjustment in the actual measurement at the lifter. most say from about .020 to .060, I like to shoot for .040. you need to figure out you threads per inch (TPI) on your adjusters. say yours are 24TPI that means 24 turns of the nut to equal one inch of movement, then just do the math. most adjusters though are fine from 1/2 to 1 full turn.
 
"340 6 pack" are the only engines to use this setup from the factory. So maybe a 1970 service manual would have the factory procedure? Otherwise camd 64 sounds reasonable. .04 is about 1 turn at 24TPI.
 
It's been a long time since I had that set up, but what I did was tighten them all so they were quiet. Then I would loosen one just enough to hear it and then start to tighten it until it was quiet again, slowly continue to tighten and your motor will start to run a little rough. Stop and loosen it about an 1/8 of a turn and you should be good.
 
If you turn the push rod back and forth between your fingers as you tighten the adjusting screw you can feel when the slack is taken up. Just go 1/2 to 3/4 turn after that. I also do this when the lifter is on the base circle of the cam.
 
Camd64 got it about right....most I have dealt with want .020 to .060 preload which is about 1/2 to 1 turn after zero lash...
 
I can tell easily enough when I have zero lash but I never knew what was acceptable on a mopar for preload. I tried 3/4 turn this morning and they are still alittle noisey . So this after noon I will go in and set them to 1 full turn. (thats where I ran them last year )
thanks all
 
just did mine with a mechanic who is mentoring me....my situation may be different, I have roller rockers, hand spin lifter as tightening untill you find zero lash, then add 1 full turn, I looked up the factory settings in the chiltons and they call for 1 1/2 turns.
 
You REALLY need to be careful with adjustments one turn and over.That's usually too much. Especially in a performance application. Performance hydraulics perform better with light lifter preloads. I go for no more than .020" preload, and most of the time that's too heavy. On some applications, I have even run zero or .002" valve lash, and yes, with a hydraulic. The reason for this is because performance camshafts are generally made to RPM higher than a stock grind. As such, a looser valve lash adjust will help them achieve this. We could get into the discussion that looser lashers make the cam "act" smaller...and that's true to a certain degree, but that tangent can consume an entire discussion all alone. Also, you need to keep in mind that tighter valve lashes with a hydraulic, can result in wiped lobes and toasted lifters. with hydrauilc adjustments, loose ls always better.
 
When I do it I make sure that my fingers are really oily. Tighten down while lightly spinning the pushrod until my finger slip. Then I usually go 3/4 turns. At 1/2 turns some of my rockers can be clackity. Some guys go 1/2 then tighten down until quite with the engine running ... like someone already said
 
MoparDreamin said:
When I do it I make sure that my fingers are really oily. Tighten down while lightly spinning the pushrod until my finger slip. Then I usually go 3/4 turns. At 1/2 turns some of my rockers can be clackity. Some guys go 1/2 then tighten down until quite with the engine running ... like someone already said
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That is a good point there but on my Comp Roller rockers trying to hold that little allen wrench and tighten with the motor is running would total hell. My luck the allen wrench would go drop down in the motor. lol

The Chevies are easy since all you need in a socket, socket extension , and a rachet. Maybe I'm just not fast enough.
 
you adjust the hydraulic in the same sequence as you would adjust a solid lifter cam...

except you adjust for preload and not lash...

like most are saying...1/2 to 3/4 after zero lash .....
 
mullinax95 said:
That is a good point there but on my Comp Roller rockers trying to hold that little allen wrench and tighten with the motor is running would total hell. My luck the allen wrench would go drop down in the motor. lol

The Chevies are easy since all you need in a socket, socket extension , and a rachet. Maybe I'm just not fast enough.
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You can adjust the nut while running, then tighten down the locks after you shut down. Cold is much less stressful though, I agree...
 
green1 said:
Per the Chilton book? good way to cost yourself $ Same with Haynes.
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That's for sure. Not sure on Chilton's but I have found so many errors in Haynes books I won't ever use one again.

Technically the 1/2~3/4 turn past zero lash is correct. If your rockers are still noisy tightening them more probably won't help cause there's a problem. Maybe some dirt/debris in them or just sloppy lifters. I had some comp lifters that were junk like that. No matter what I did I couldn't get them quiet. replaced them with a Lunati cam/lifter set and it's fine.

Even though 1/2~3/4 turn is technically correct Strokerscamp does make a good point on setting them light. It will generally allow the engine to rev a little more. Some racers just take out the lash and only a couple thous. more. That way if the lifter pumps up it won't hang the valve open.

BTW: Are you positive you don't have small header leaks as that can sound like clacking lifters?
 
Preload is not lash. The opposite really and I think it's important to make that distinction when we talk about it. What we are talking about is the distance between the top of the lifter's plunger or pushrod seat, to the bottom of the plunger retaining clip.
"Counting the turns" is a general way to do it. It's dependant on the thread pitch of the adjuster and that can vary, especially with the cheaper offshore stuff.
The type of lifter is important to know:
- Hydraulic factory type lifters are forgiving and can ususally run well and quietly with preloads as short as .020 to as much as .060. These are generally used with most older cam grinds, and the new grinds that are milder cams but still fast rate.
- Anti-pump-up hydraulics are designed to not compress as much under working load because the compression is what causes loss of control of the valve, or valve float. These lifters take less preload and the spec will depend on the lifter manufacturer. Generally you want a smaller window. I use .010-.020" Any more and you may end up hanging valves open. These are the "optional" numbers in Comp for the faster rate medium to large camshafts, all of Lunatis, all Bullet, and IIRC all Hughes fast rate cams. These, even when the preload is right, may be noisey and sound much like a solid lifter with too much lash.
-Variable duration lifters are anotehr aftermarket deal to try and get some compromise between big cams and "street manners". Again, concult the manufacturer because they will be noisey but still be set right. I don't use them so I can't tell you guidelines...lol. If you need variable duration lifters, you needed a solid lifter profile as far as I'm concerned.

One other note.. If youve ever used header lock bolts on the heads, the washers on them will sound like a loud lifter until the bolt backs out and preloads them.... Usually takes 5-10 heat cycles.
 
Thank Moper

What type of lifter is a stock factory roller in a Dodge Magnum 5.9 engine?
What would you suggest for inital adjustment (after primmed)? Thank you.
:prayer:
 
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