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Poly locks without the set/lock screw?
Comp roller rockers and poly locks with no set screws. Can someone educate me on what determines if you run the set screws or not? TIA.
https://cimg8.ibsrv.net/gimg/www.off...ef2dcdc7df.jpg |
You run the locking set screw.
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Originally Posted by Rookie
(Post 4903898)
You run the locking set screw.
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Originally Posted by Knot 4 Me
(Post 4903900)
That is what I thought. Lol! But I don't claim to know everything (anything, actually) so when I went to check on a buddy who just pulled a head due to a blown head gasket I was surprised to see there were no set screws on any of the poly locks. Motors probably have 150 - 200 hours on them this way. Originally build by Baker and then rebuilt by a shop in MO that Myrick Coil recommended (can't think of it off the top of my head) so either Baker set it up this way originally or the second shop forgot to put them in. Heads are Dart Pro I's.
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Originally Posted by articfriends
(Post 4903926)
He musta had stud girdles and trusted them to hold the nuts or your mistaken on the poly locks with no set screw and they were crimp nuts. Without set screws those nuts would back off very quickly and beat valve train to death, Smitty
Not familiar with crimp nuts. On another weird note, he thought all the poly lock nuts were ran all the way down tight. Again, I wasn't there so no idea why he thought that when he backed them off but that is what he said. Not sure how it would have survived with that much pre-load either if that is really how they were. https://www.summitracing.com/parts/c...SABEgIh1vD_BwE |
Not sure how they would not back off without the set screws
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Originally Posted by Griff
(Post 4903931)
Not sure how they would not back off without the set screws
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Loc-Tite probably
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Mystery solved. When he showed me the poly lock I didn't have my readers with me and when I asked about set screws and he said there were none I took his word and just snapped a quick pic. Had I looked more closely, even with my 60 year old eyes, I would have seen no daylight down the barrel of the nut and would have known something was in there. I had my buddy worried enough that he was about to call the builder and he decided to take one last look and sure enough, down in the nut the set screw was there (and there in all the other ones). He had never messed with an engine with roller rockers/poly locks before so he didn't know to look for the screws and just backed the nuts off. Now we know how the nuts never backed off.
Apologies for the wild goose chase! |
Crimp nuts are Stover nuts.
The nut is deformed and pressed in slightly in 3 locations 120° apart. This puts tension on the threads as the nut expands as it's threaded onto the rocker stud etc. Standard stock style rocker roc. |
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