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HYD lifter pre load?????

Posted By: jp15

HYD lifter pre load????? - 05/10/13 10:40 PM

totally new to Me. Question ? can I adjust my adjustable rockers down to bottom out and back off say 60 thou. to achieve proper pre load?.( lobe on base ) ( HYD cam) tried the finger turning way,but rod up against rocker with adj. backed all way out and has slight resistance there ???. probably a thread here on this but I can't find it.
any help appreciated.
Thanks, Jim
Posted By: HPMike

Re: HYD lifter pre load????? - 05/10/13 10:51 PM

Quote:

totally new to Me. Question ? can I adjust my adjustable rockers down to bottom out and back off say 60 thou. to achieve proper pre load?.( lobe on base ) ( HYD cam) tried the finger turning way,but rod up against rocker with adj. backed all way out and has slight resistance there ???. probably a thread here on this but I can't find it.
any help appreciated.
Thanks, Jim



Not quite getting what you mean..??

I go 3/4 a turn after the adjuster seats in pushrod. You can go more(id say no more than 1.5 turns) or less(no less than 1/2 a turn. But I have been doing it this way(3/4) for years with no problem. it does take some touch..I do not use a tool to find the "seated" point, but use my fingers as it is really tricky to find the exact point that the "lash" is out.

Important to make sure that the rocker adjuster is in its proper "sweet spot" in the rocker after you are done. Depends on the mfg as they arent all the same. If you eff this up you will get rocker/adjuster failure or lack of oiling to the p/r.

Its not rocket science..

MB
Posted By: Crizila

Re: HYD lifter pre load????? - 05/10/13 10:57 PM

Quote:

totally new to Me. Question ? can I adjust my adjustable rockers down to bottom out and back off say 60 thou. to achieve proper pre load?.( lobe on base ) ( HYD cam) tried the finger turning way,but rod up against rocker with adj. backed all way out and has slight resistance there ???. probably a thread here on this but I can't find it.
any help appreciated.
Thanks, Jim

Yes, you can do it that way as long as the lifters are completely void of oil. As long as you are within the range of the lifter plunger travel it will work, but I wouldn't suggest it. It sounds like you have other valve train issues ( push rods too long, etc ) that will cause incorrect valve train geometry - that can lead to other issues such as poor or incorrect oiling. Suggest you get yourself an adjustable push rod and start from there. If you are running rocker shafts, you might consider shimming them to get the clearance you need if you don't want to buy the correct length push rods. It would be better than your suggested adjustment method.
Posted By: jp15

Re: HYD lifter pre load????? - 05/10/13 11:01 PM

lifters are dry. have the mopar type cup and ball end push rods and 273 type rockers.
Posted By: jp15

Re: HYD lifter pre load????? - 05/10/13 11:04 PM

there ya go . lol, I have some brass shim stock I'll try that. Thanks
Posted By: HPMike

Re: HYD lifter pre load????? - 05/10/13 11:14 PM

Quote:

there ya go . lol, I have some brass shim stock I'll try that. Thanks



nooooooo.....
Posted By: jp15

Re: HYD lifter pre load????? - 05/10/13 11:48 PM

Quote:

Quote:

there ya go . lol, I have some brass shim stock I'll try that. Thanks



nooooooo.....




lol, crap whachyou mean man.
Posted By: HPMike

Re: HYD lifter pre load????? - 05/11/13 12:00 AM

Quote:

Quote:

Quote:

there ya go . lol, I have some brass shim stock I'll try that. Thanks



nooooooo.....




lol, crap whachyou mean man.



Its just a personal thing with me..Why use shims when all you need is correct p/r's? Just doesnt make any sense. You could also cause geometry problems if everything is good now. Measure for length and get the right pushrods if the ones you have wont work. If you dont need anything exotic, and it sounds like you dont, then they arent all that expensive.

MB
Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 12:09 AM

I hear ya , just don't understand why this won't work? the rods are shorter than the factory rods, if I used the factory stamped rockers I wouldn't have noticed this. It's only a .528 lift COMP cam.??? using the adj. rockers so the rod doesn't pierce the stamped rocker.
Posted By: MR_P_BODY

Re: HYD lifter pre load????? - 05/11/13 04:33 AM

Quote:

I hear ya , just don't understand why this won't work? the rods are shorter than the factory rods, if I used the factory stamped rockers I wouldn't have noticed this. It's only a .528 lift COMP cam.??? using the adj. rockers so the rod doesn't pierce the stamped rocker.



What is so difficult about doing it the RIGHT way...
on the base of the cam... turn the adjuster in till
the push rod has drag or stops turning... then give
it 1/2 to 3/4 turn... done.. move to the next one..
if your off a 1/4 turn its not gonna kill you
Posted By: Cab_Burge

Re: HYD lifter pre load????? - 05/11/13 04:54 AM

Quote:

Quote:

I hear ya , just don't understand why this won't work? the rods are shorter than the factory rods, if I used the factory stamped rockers I wouldn't have noticed this. It's only a .528 lift COMP cam.??? using the adj. rockers so the rod doesn't pierce the stamped rocker.



What is so difficult about doing it the RIGHT way...
on the base of the cam... turn the adjuster in till
the push rod has drag or stops turning... then give
it 1/2 to 3/4 turn... done.. move to the next one..
if your off a 1/4 turn its not gonna kill you


If your using the solid lifter pushrods from the 273 on a stock type set of hydraulic lifters your fooling with fate, loof to have 1 to no more than 3 full threads of the adjuster exposed under the bottom of the rocker amr with .015 to .045 lifter preload, I like and use 1/4 to 1/3 of a turn after zeroing the liftere clearances out, zero preload plus 1/4 to 1/3 turn in for hydraulic lifter preload
Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 10:56 AM

Quote:

Quote:

I hear ya , just don't understand why this won't work? the rods are shorter than the factory rods, if I used the factory stamped rockers I wouldn't have noticed this. It's only a .528 lift COMP cam.??? using the adj. rockers so the rod doesn't pierce the stamped rocker.



What is so difficult about doing it the RIGHT way...
on the base of the cam... turn the adjuster in till
the push rod has drag or stops turning... then give
it 1/2 to 3/4 turn... done.. move to the next one..
if your off a 1/4 turn its not gonna kill you

Not a thing difficult about adj. valves, have done it a few times the last 26 years of racing solids. like I said in my post it has no clearance with the adj backed right out of the rocker???? haven't done this with adj rockers on hyd cam. what do you call resistance to turning. (slightly, hard to turn, or till it stops turning then a extra turn 1/4 er whatever..


Posted By: MR_P_BODY

Re: HYD lifter pre load????? - 05/11/13 12:53 PM

Not a thing difficult about adj. valves, have done it a few times the last 26 years of racing solids. like I said in my post it has no clearance with the adj backed right out of the rocker???? haven't done this with adj rockers on hyd cam. what do you call resistance to turning. (slightly, hard to turn, or till it stops turning then a extra turn 1/4 er whatever..






Till you get all the free play out of it
Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 12:58 PM

Quote:

Not a thing difficult about adj. valves, have done it a few times the last 26 years of racing solids. like I said in my post it has no clearance with the adj backed right out of the rocker???? haven't done this with adj rockers on hyd cam. what do you call resistance to turning. (slightly, hard to turn, or till it stops turning then a extra turn 1/4 er whatever..






Till you get all the free play out of it




I have no free play, clearance etc
Posted By: MR_P_BODY

Re: HYD lifter pre load????? - 05/11/13 01:16 PM

I have no free play, clearance etc



Can you back the adjuster out till you have some play
in the PR... snug the adjuster till all free play
is gone then once its at that point give the adjuster
1/2 turn more... thats it
Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 01:31 PM

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play
Posted By: MR_P_BODY

Re: HYD lifter pre load????? - 05/11/13 01:34 PM

Quote:

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play




Sounds like your push rods are too long
Posted By: JohnRR

Re: HYD lifter pre load????? - 05/11/13 02:01 PM

Quote:

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play




Your pushrods are TOO LONG , you need to get or make a checker pushrod and figure out the length you need and have a set made.

The purpose of rockers shims is to correct incorrect rocker to valve geometry , they are NOT for correcting for pushrods that are too long , I don't care who say they are, they are WRONG.

If your pushrods are against the rockers without the adjusters then you need new pushrods , plain and simple.
Posted By: Cab_Burge

Re: HYD lifter pre load????? - 05/11/13 02:34 PM

Quote:

Quote:

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play




Your pushrods are TOO LONG , you need to get or make a checker pushrod and figure out the length you need and have a set made.

The purpose of rockers shims is to correct incorrect rocker to valve geometry , they are NOT for correcting for pushrods that are too long , I don't care who say they are, they are WRONG.

If your pushrods are against the rockers without the adjusters then you need new pushrods , plain and simple.

Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 02:51 PM

OKeeDookie I'll make a checking rod and go ater
Posted By: Crizila

Re: HYD lifter pre load????? - 05/11/13 02:51 PM

Quote:

Quote:

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play




Your pushrods are TOO LONG , you need to get or make a checker pushrod and figure out the length you need and have a set made.

The purpose of rockers shims is to correct incorrect rocker to valve geometry , they are NOT for correcting for pushrods that are too long , I don't care who say they are, they are WRONG.

If your pushrods are against the rockers without the adjusters then you need new pushrods , plain and simple.

I think I said that, and I agree with you, but it sounds like he just doesn't want to buy shorter pushrods? Not the perfered way to go, but he can solve his clearance problem by shimming the shafts.
Posted By: Performance Only

Re: HYD lifter pre load????? - 05/11/13 05:48 PM

I can tell you that I've repaired quite a few heads from people using regular shim stock to raise the shafts and they end up cracking.
Posted By: JohnRR

Re: HYD lifter pre load????? - 05/11/13 08:22 PM

Quote:

Quote:

Quote:

as I posted, have the adj. out of rocker and rod is against rocker. NO clearance???. rod is a mopar mech cup and socket type rod and is a bit shorter than a stock hyd. rod. cam base should be smaller than a stock cam so I don't know why I have no free play




Your pushrods are TOO LONG , you need to get or make a checker pushrod and figure out the length you need and have a set made.

The purpose of rockers shims is to correct incorrect rocker to valve geometry , they are NOT for correcting for pushrods that are too long , I don't care who say they are, they are WRONG.

If your pushrods are against the rockers without the adjusters then you need new pushrods , plain and simple.

I think I said that, and I agree with you, but it sounds like he just doesn't want to buy shorter pushrods? Not the perfered way to go, but he can solve his clearance problem by shimming the shafts.



I wasn't really trying to point out who said it , I know what you were saying , sometimes people fish for the answer they want to hear and don't want to hear the truth because of the cost involved.

In the past when it's said that shims are the way to fix this problem and someone said not it's not a person would come back well this big name racer/parts seller and/or that big name racer/parts seller list them for that exact purpose .... It's WRONG ...
Posted By: jp15

Re: HYD lifter pre load????? - 05/11/13 08:35 PM

NOT fishing for what I want to hear, just want to know why I had no clearance between rod and rocker, thinking the Comp lifter (882-16) has a higher seat height than stock lifter, only thing that makes sense to Me . and yes trying to use what I have for parts.
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