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what kind of damage did the rocker arm pivot receive? they may be broken also but if so which came first.
i will throw a few things out there, dont beat me up here im just trying to help.
could it be harmonics
too much lash
coil bind
bottom of retainer hitting top of guide at max lift
valvetrain geometry
rocker arms hitting spring retainer ie.while on basecircle of cam (lash cap would fix)
rocker arm pivots upside down when assembled
last but not least stud girdle pushed to far down on polys and binding with the rocker arms

i have been thru all the above with some past engines just some things to check
 

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Lots of things to look at.

I split some lock nuts by being lazy & trying to get a thou. or two by tightening the nut after the poly is set. I tightened the nut to tight & split the whole deal. A couple looked a lot like yours. I replaced the whole set. No problems since.
 

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poly locks

Can you post some more pictures were the poly lock on the flat part of the roller trunnion bar , Have you indexed the push rods for proper length, were they all bad ? poly locks, more pictures needed , what cam size, did you check the
 

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mo balls than $cents$
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Can you post some more pictures were the poly lock on the flat part of the roller trunnion bar , Have you indexed the push rods for proper length, were they all bad ? poly locks, more pictures needed , what cam size, did you check the
:D we're thinking the same thing;) his polys were bigger than the trunion flats for the polys, then it was squeezing down as the valve went down, bet you were adjusting valves alot weren't ya. guess how i know that sign:)hand:)sphss:D
 

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Discussion Starter · #7 ·
what kind of damage did the rocker arm pivot receive? they may be broken also but if so which came first.
i will throw a few things out there, dont beat me up here im just trying to help.
could it be harmonics
too much lash
coil bind
bottom of retainer hitting top of guide at max lift
valvetrain geometry
rocker arms hitting spring retainer ie.while on basecircle of cam (lash cap would fix)
rocker arm pivots upside down when assembled
last but not least stud girdle pushed to far down on polys and binding with the rocker arms

i have been thru all the above with some past engines just some things to check

Harmonics maybe
I set lash cold at 15 calls for 18 hot both
checked for coil not even close
retainer to rocker all good
retainer and guild all good
valvetrain geometry spot on
rocker trunions right side up (my first thought)
stud girdle has over 1/2in clearance


polys ***ed
trunions ***ed

This problem started when I put the stud girdle on

ran comp. cam polys for 3hr with no problems. Then broke one stud tip ( to short) replace stud and added girdle.

Thanks for all the help
keep it up need :)bulb
 

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Discussion Starter · #8 ·
:D we're thinking the same thing;) his polys were bigger than the trunion flats for the polys, then it was squeezing down as the valve went down, bet you were adjusting valves alot weren't ya. guess how i know that sign:)hand:)sphss:D
This was my second idea, they mic. the same as the comp. locks and fit the trunions fine.
 

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never checked them hot?
I ran the valves on nephews engine last week
everything looked great and he running a set of Jomar girdles and poly locks.

maybe too much play??


your pic shows two different areas of wear??
 

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A lot of times with those particular stud girdles, they dont fit properly and you find yourself hammering to get the girdle on and off if you dont loosen it all the way. The girdle is tweaking on the polylocks and when you tighten it on for good it has the polys in a bind. Then you go and run it and they fatigue. Maybe look into a different brand of stud girdle.

T.
 

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Discussion Starter · #13 · (Edited)
1314 Ultra-Lite Stud Girdle - Chevrolet 396-500 BOWTIE DART & MERLIN Heads

I laid the girdle on the heads strarted the locks and adj. all valves, then lifted the girdle up the locks tell slight hand tension was welt the tighten up set screws.

Came with out instructions. So maybe I did something wrong.

Or is this type stud girdle junk????

 

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steelcomp was here
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If the valves are adjusted correctly and everything is tight, there isn't really anything that can go wrong with the polys. If the stud is a little tweaked, it's really not going to affect the poly since the poly is just a continuation of the stud. Same with the rocker. The tunion and poly are pretty much going to stay in line with eachother. What it looks like, is the bottom of those two polys were pounded, which makes it look to me like there was excessive lash. It's important that after the girdle is installed and everything tight that you go back and one at a time, adjust each valve loosening the girdle only at that valve as you adjust, then tighten, and move to the next one. Don't try and adjust all the valves and then tighten the girdle as a unit, because there will be a good chance that the girdle will pull a couple of rockers out of adjustment because of some misalignment, be it the stud or the girdle, or both. It wouldn't take much to set up a destructive harmonic to beat up a poly like that.
The four bar girdle like Outlaw has is my favorite. I don't like the one piece girdles because it's very hard to tell when the girdle is fitting corectly. With the four bar, you can also install all the polys and do an initial valve adjustment before installing the girdle. That ultralight girdle looks a little flimsy and not very user friendly. If you didn't adjust your valves again after you tightened the girdle, my guess is that was where the damage came from.
JMO
 

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Soaker...I'll have to ask, with the type of running you do....could the cam you have maybe be a little on the big side? And for the RPM you're turning, why didn't you go with a hyd roller cam?
 

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Discussion Starter · #17 ·
If the valves are adjusted correctly and everything is tight, there isn't really anything that can go wrong with the polys. If the stud is a little tweaked, it's really not going to affect the poly since the poly is just a continuation of the stud. Same with the rocker. The tunion and poly are pretty much going to stay in line with eachother. What it looks like, is the bottom of those two polys were pounded, which makes it look to me like there was excessive lash. It's important that after the girdle is installed and everything tight that you go back and one at a time, adjust each valve loosening the girdle only at that valve as you adjust, then tighten, and move to the next one. Don't try and adjust all the valves and then tighten the girdle as a unit, because there will be a good chance that the girdle will pull a couple of rockers out of adjustment because of some misalignment, be it the stud or the girdle, or both. It wouldn't take much to set up a destructive harmonic to beat up a poly like that.
The four bar girdle like Outlaw has is my favorite. I don't like the one piece girdles because it's very hard to tell when the girdle is fitting corectly. With the four bar, you can also install all the polys and do an initial valve adjustment before installing the girdle. That ultralight girdle looks a little flimsy and not very user friendly. If you didn't adjust your valves again after you tightened the girdle, my guess is that was where the damage came from.
JMO

I did check some of the valves but not all of them as they were right where I set them.
 

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Discussion Starter · #18 ·
Soaker...I'll have to ask, with the type of running you do....could the cam you have maybe be a little on the big side? And for the RPM you're turning, why didn't you go with a hyd roller cam?
You been talking to MikeT:D
I'm no cam guy but I'm starting to think so to.


I went with my cam guys recomendation. I will go hyd next time.
 

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SS, I had a cheap set of poly locks do that. My guess is more Made in China crap. Replaced them with a set from Comp Cams and problem solved.
 
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