302 valvtrain problems

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Sep 9, 2009 | 07:47 PM

93F22A6

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302 valvtrain problems

Ok so I just re-ringed my 76 302. It has the stock cam and 64' 289 heads that are on there last leg(going to be replaced soon) Anyways after the rebuild it start to develop a slight valvetrain knock/nosie(sounds similar to a loose rocker arm almost). I just readjusted the valves and it's still there. I'm stumped at the moment really, not sure what is could possibly be. (info on the heads, they need new seats and guides but still useable for now is what the machine shop told me) Any help will be appericated, it seems like the truck is cursed with problems left and right after you fix something else.

Sep 10, 2009 | 02:18 PM

93F22A6

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bump, anyone have any ideas.

Sep 10, 2009 | 02:38 PM

lew52

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Soundes like a bad lifter , with the valve covers off start it , you should be able to feel with one it is , then pull the rocker & push rod & have a look at them ... Lew

Sep 10, 2009 | 03:00 PM

gfw1985

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From: Raphine, Virginia

Another possibility is a rocker arm stud has pulled loose/stripped. They were pressed in, not screw in. I had to have a machine shop replace two of them with screw in studs. Whoever (PO) rebuilt the engine must have dropped the head and one was bent, one pulled and stripped.

Sep 10, 2009 | 06:45 PM

93F22A6

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At first I thought it was a bad lifter but my dad thought it just needed to be re-adjusted. They both in my opinion are probably why if that would cause it. We could have bent one of the studs while putting in the engine. The lifters got wet, but we soaked them for about 4 days after cleaning them. Anyways I'm looking at getting a new cam and lifter for it anyways(230 dur. .512 lift) That and a fresh set of heads. The machince shop had a set of rebuilt 302 heads(new guides, seats, seals, and decked) for 300. Then the cam from a friend of mine for 150 with new pushrods.

Sep 12, 2009 | 08:25 AM

42x

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From: Davis, CA

I am having the same problem but I think mine is related to a weak valve spring. Again "I THINK" so not 100% sure but it seems to be pointed this way.