Valve cover bolts won't stay snug.

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hey mister

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Ok...valve cover bolts won't stay snugged down.
Stock 78 sbc. Stock bolts, stock cover. New cork gasket.
Man, I'm getting tired of leaking oil out the back of the head valve galley. And just for the record, the valve cover mating surface on the head is not a machined finish.
What might the collective suggest?
Thanks guys.
 

fast 99

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About the only thing that worked at all on those for me was RTV. 3/16th bead on gasket, set the cover on head, install the bolts to just barely tight. Come back the next day, do a final tighten. Check again in after a couple heat cycles. Spreader bars help a lot.
 

75gmck25

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Stamped steel covers should have small steel load spreaders, which are also usually arched a little to create a spring effect as you tighten them down. That should help.

Rubber gaskets with metal reinforcement usually work well, but they are quite expensive. I used them with my aluminum valve covers, which have a very rigid flange area, and they seal well. However, the gaskets were almost as expensive ($60) as the inexpensive Summit-branded aluminum valve covers ($90) I used.
 

legopnuematic

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Also verify that the valve cover flange is straight, it’s not unusual to see them all twisted up or puckered up from being over tightened to as an attempt to stop a leak with bad gaskets.

And agree on the spreader bars.
 

Ricko1966

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As said by multiple people you should have spreaders,they were factory. I never had a problem with cork gaskets I glued them to to the valve cover,greased them on the head side. If I was having a problem,like you seem to be, I'd loctite studs into the head and switch to nylock nuts.
 

Oldbear42

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Also verify that the valve cover flange is straight, it’s not unusual to see them all twisted up or puckered up from being over tightened to as an attempt to stop a leak with bad gaskets.

And agree on the spreader bars.
From a young age, I was taught to give each bolt hole a light tap with a ball-peen hammer (ball-peen held to metal and stuck with another hammer - maybe plastic dead-blow for the safety people) to straighten out or dome the metal around the hole as it bends "down" over time and tightens.
 
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hey mister

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Update:
Picked up a set of metal reinforced rubber vc gaskets. Also a set of spreaders and a set of locking head screws. (I had to get bolts anyway because of the spreaders.)
 

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