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Discussion Starter #1
I,read many of the posts on how to adjust the hydraulic lifters and have redone mine four times. Each time one or more have been very loose. I have a 350SBC with cast bowtie heads, screw in studs & guideplates. The Comp Cams Extreme 280 cam and matching lifters came out of my buddies engine with only a few hundred miles (lifters carefully boxed and identified so they went back on the same lobe). The heads were surfaced so I used a pushrod length checker to get the correct length hardened pushrods.

Before I read the posts about roller tip rockers I purchased a set of Proform 1.6 chrome moly roller tip rockers. I'm not sure if the problems others have had are with the cast chrome moly ot the cheaper stamped rockers. I seem to have a problem similar to another guy who did not really get an answer. When the cam lobe is on the heel, I can loosen the adjusting nut a couple turns easily but once I begin to slowly tighten the nut while turning the pushrod It seems like the pushrod suddenly binds. It will not go from loose to feeling resistance. If I back off the nut a fraction of a turn the pushrod will again turn freely. I can't seem to get the lifters adjusted without a little clacking.

My question is are the rockers the problem, could the pushrod ball ends be a little large? Or could the groved balls not be fitting properly in the rocker body. Any ideas ? I'd prefer to not adjust with the engine running. And I don't want to go to tall valve covers so full roller rockers are out of the question. Thanks
 

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i bought one of those push rod length checkers too and could never get it to give me the correct reading and i finally came across an article that said they were only to be used on stock type rocker arms.you may have simply forced some of the oil out of the lifters while doing the adjusting and siply need to readjust after it is running.that system is only ment as a temporary adjustment.
 

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You may have a lifter going down.

If everyother way has not worked try this:

Turn the engine over until an intake is wide open. On that matching exhaust rocker use a feeler gauge with the thinest blade it has. Slide it in and out as you tighten that nut. When the feeler gauge binds pull it out and go just past 1/4 turn. Do that to each valve.
 

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Is this a fresh rebuild? If so there may be a plug missing
in the oil passage above the oil pump. To check this, remove
the oil pressure sender at the back of the intake, next insert
a dipstick, coat hanger, whatever down the hole. It should
go in about 8 1/8". If it's more like 10" sorry but the rear
main cap has to come off. I'v seen this cause all kinds of
valve adjustment problems & if ignored the engine won't
last long.
 

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Discussion Starter #6
Many Thanks to all the suggestions, NXS's tip to use a feeler gauge worked great after I replaced the Proform Chrome Moly roller tip rockers with some good Crane stock style ones. Seems the Proform Balls did not fit properly and caused the socket in the rockers to Gall making adjustment impossible. Had plenty of lube prior to starting so I guess you get what you pay for. Dale
 
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