I was reading a copy of old back in the day article where Jim Lane the Buick GS racer mentions to put .060 shims in after a few weeks of driving the 66 GS to restore the lost spring tension. Was there enough undercut in the heads for the the shims? Just a curiousity question.
It had already done it a couple of times under load. This was to make sure it wasn't spark or fuel. Explain to me how rpm in neutral kills rod bearings. I've been messing with engines all my life (I am 68.) and I have never heard this. I would have already ruined several engines if this were the case. Of course, the duration of these pulls was short, no prolonged.
I have no idea. This engine was built 15 or 16 years ago and driven about 2500 miles. I believe it was rebuilt as stock. They probably reused the original valve springs.
Winging up to 4/5 grand for a second usually wont hurt anything, but 5 seconds or more is hell on 'em Maybe someone else has a more concise explanation as to "why"
Well, it was more than 5 seconds. If someone has a good explanation, I would like to hear it. Anyway, its already done.
I forgot I had a Moroso valve spring tester. I will give it a go next week and see what I really have.
The approval procedure at Pontiac to put a new motor into production was to run it for many hours at 4500 with only a brief stop in the middle of the hours for a oil and filter change. If after this test run the engineers upon disassembly found only what they considered a normal level of ware then the motor went into production. I can't fathom any sonario where a Buick motor under the same test conditions would eat up rod bearings from running with no load!!
Well, my Moroso valve spring tester won't fit the rockers but I can take one hand and with my thumb and forefinger depress the valve spring. That is damn sure not enough! Any recommendations on where/what to buy? I guess I will need shims and valve spring height tool and shims, as well. Anything else I am missing?
By any chance does your engine only have the outer valve springs, with no inner springs? It should have inner springs and outer springs. Some builders will leave the inner springs out for the initial engine break-in run, then install them later. I usually buy stock outers and Isky inners. TA Performance, and Nailheadbuick.com are popular suppliers for performance springs, or go right to a manufacturer such as Comp Cams. Your cam specs and your driving style will determine what the best springs are for you.
TA has stock springs 75 seat and 195 open. and there stage 1 springs 90-seat and 230-open. your rocker arms must be steel than in later years they have the lighter aluminum rocker arms. roc auto has just the outer springs for $3.25 each.
Well no wonder I had va lve float. Every inner spring is broken into 3 pieces, it seems. I've only looked at 8 of them, so far. How can I tell what caused this? I'm thinking bad metallurgy. They are broken pretty clean with sharp points on the ends.
Does your cam have a stock amount of lift? when the motor was rebuilt and the springs installed they may have been compressed too much which took the inner spring way passed it’s coil bind point. This would have very much stressed out the spring! consider yourself very very lucky that a broken section did not unwind its way thru the outer spring because that would have either held a valve open or busted out the keepers resulting in a dropped valve.
Stock cam. Until I get my height mic, I can't say for sure but it appears the installed height was in the 1.7 range no coil bind that I can tell.
i didn't know they had the nail head outer shims with the bigger center hole for the inner spring. i always thought just Carmen had them.
No coil bind you say!? Just look at what I guess from your photo is the broken bottom sections of the inner springs ! The bottom last 3 coils are all practically stacked up, I mean what more evidence does one need that something was not right! I am willing to bet that if the motors Cam lift is stock that those springs ( at least the inner ones ) are not true good replacements for the factory springs. I would also confirm that none of your push Rods are bent.
