wonder how this happened

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twayne24365

twayne24365

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decided to check over and adjust the valves today, so i started the beast up and warmed it up before getting started, only to find this on #5 intake
 

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I would guess that the rocker contacts the spring retainer at or near max lift, pushing on the retainer and unloading the keepers, allowing one of them to come out. You are extremely lucky.
 
you, upon investigation i see the problem, when i was setting up the motor i had to clearance the bottom of the rocker to clear the retainer, checked it and nothing hit. but i guess when it heated up the aluminum expanded enough to make contact. got a set of rocker shaft shims ordered to raise them up slightly instead of clearancing them all again. and yea im glad i decided to check the valves today, ive been pretty lucky with stuff!
 
d55dave said:
I would guess that the rocker contacts the spring retainer at or near max lift, pushing on the retainer and unloading the keepers, allowing one of them to come out. You are extremely lucky.
Click to expand...

Yep.
You lead a charmed life........that could have been real ugly.
I think a lash cap might be a better fix.....it will raise the rocker another .060 or so off the retainer and open up the gap between the two , though raising the shaft won't hurt either.
Maybe a combo platter to maximize clearance ?
 
Also give your rockers a thorough once over to make sure there is no damage that will come back to bite you later.
 
i checked the rocker and the roller still rolls smooth but i cleaned off the sharp edges, i have a shim kit on the way with .010 .015 and .030 thicknesses. the geometry is my next question, the roller tip is perfect as is, at full lift it rolls right into the center of the valve, if i raise the shafts up how will this effect the contact pattern?
 
tubtar, lash caps may be the ticket, i have a set of them so maybe ill put them on and check everything. when i built the motor i clearanced the rockers and mocked all of them up to make sure they didnt hit, i guess i didnt take into consideration how much aluminum expands when it gets hot.....live and learn right...
 
If you look at that damage real close, you may come to a slightly different conclusion than expansion.
Check the damage beside and on the roller axis.The nearest damage looks like the keeper pummeled it. But look a little further outboard, both sides. There you will see the spots where the retainer edges bit into the rocker. If it was on the loose keeper side a guy might conclude that this happened after the keeper popped out. But notice both sides are so marked. that leads me to conclude that it actually began before the keeper popped and therefore that the retainer is just too tall, for the rollertip design.I wonder if the arm didnt just press onto the retainer enough to allow the loc to pop out. If this makes sense to you(you are the guy with eyes on it), You might consider a different retainer alltogether with a lower profile or the aformentioned lashcaps.If Im right the shims may not help. Then reassemble without the shaft shims and re-read the geometry.
As always just mho, and yes you are the guy with most luck.
 
yes i have, there is no way that it expanded that much, my mistake lol, im glad it wasnt costly tho, set me back 6 bucks for a new lock and 15 for the shims....better than thousands for whats in the motor
 
When you are checking your geometry and clearances are you doing it with solid lifters installed? If you are doing this with hydraulic lifters you are not actually seeing what max lift looks like as the lifters collapse some with no oil pressure.
 
I was using Hughes cool faced lifters, and an adjustable pushrod. Hughes dual springs recommended for the can and comp 10* super retainers and locks
 
d55dave said:
When you are checking your geometry and clearances are you doing it with solid lifters installed? If you are doing this with hydraulic lifters you are not actually seeing what max lift looks like as the lifters collapse some with no oil pressure.
Click to expand...

And the bad thing about lifters is the contact area where the pushrod ball seats is a different dimension to the top of the lifter between hydraulic and solids. That's why they take different length pushrods. I would be tempted to check into some beehive springs. That would end your problems as long as they spec close to the springs you are using. tmm
 
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