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boat737
01-02-2018, 10:20 AM
I have a small oil leak at the lower forward edge of the left valve cover. I had noticed a couple drops of oil on the garage floor, and it took me over an hour to trace it from the bottom of the bell housing (first suspected rear main seal), up the block plate to the rear of the oil pan (then suspected the oil pan gasket), then up the block to the left head (found a drop of oil on the #8 cyl exhaust header flange), up the head to the rear of the valve cover, along the lower edge to the front lower edge of the valve cover.

I haven't pulled the valve cover off yet. I don't want to crank down on the valve cover bolts yet either, as I don't trust myself to have the "touch" as to how tight to tighten those bolts down. (I may not know how tight they should be, but I do know that they should not be cranked down very tight in order to not destroy the valve cover.) All I've done so far is to put a wrench on the valve cover bolts to make sure they were snug and not loose, and to clean up all the oil so that I can track it better now.

It's a 427w Dart, Edlebrock Victor Jr. Heads., and the motor has 200 miles on it so far. I figure my two options at this point are tighten the bolts a tad more, or pull the valve cover and inspect the mating surfaces and gasket.

I'm looking for any info and advice on what I should be looking for, or how I should address the issue. Is this common? How tight is tight on those valve covers? Thanks all.

edwardb
01-02-2018, 10:29 AM
What valve cover gaskets are you using? Some are way better than others. I chased an oil leak on the covers on one of my small block builds until I switched to these: https://www.summitracing.com/parts/fel-vs13264t/overview/. You would need to confirm this is the right one for your engine. But this family of products from Fel-Pro is excellent. Seal well, have stops to prevent over-tightening, and stand up to being taken on and off repeatedly. That's assuming your valve covers is where the oil leak is coming from. Always interesting to chase those things down.

boat737
01-02-2018, 10:48 AM
Hi Paul. Don't know what the gasket is, it's what the builder put in. It looks to be a rubber or silicone type, it's a teal blue color from what I can see so far.

You mention... "assuming your valve covers is where the oil leak is coming from." Is there another possible location around that area that may be suspect?

edwardb
01-02-2018, 11:01 AM
Hi Paul. Don't know what the gasket is, it's what the builder put in. It looks to be a rubber or silicone type, it's a teal blue color from what I can see so far.

You mention... "assuming your valve covers is where the oil leak is coming from." Is there another possible location around that area that may be suspect?

I only meant that oil leaks can originate in one place and then show in another and sometimes be pretty tricky to trace down. Cleaning everything up and then watching closely should help to confirm if it's the valve cover gasket. If it's not that or something else you can identify, you could use oil leak dye to trace it down. I've personally never had to go that far but it's an option if you can't find it.

Try tightening the cover bolts, all around and evenly. Don't overdue it though. Shouldn't take a lot to keep them from leaking if the gasket is doing it's job.

Joee
01-02-2018, 11:40 AM
2x on those valve cover gaskets. They are great especially for removing and reinstalling valve covers. Mine are prob 4 or more years old and not a drop, the fasteners dont even need to be that tight.

NAZ
01-02-2018, 11:43 AM
I concur with Paul on the use of silicone type valve cover gaskets. When you have solid lifters you remove the valve covers frequently and these hold up where others don't. Most street cars use hydraulic lifters and the owners will rarely remove a valve cover. These type should last a long long time for these folks. Since I remove mine more frequently than most I use a silicone based adhesive on the valve cover side and nothing on the head side. That ensures that the gasket stays with the cover. For your application I'd use these without any sealer at all.

FLPBFoot
01-02-2018, 02:40 PM
Yes these look great! Good price too!

AC Bill
01-02-2018, 07:32 PM
Now the engine has done few heat cycles, the cover bolts just may need a slight snugging up, to solve the leak. Use a 1/4" drive, and just tweak them a tad.

cgundermann
01-02-2018, 07:46 PM
Now the engine has done few heat cycles, the cover bolts just may need a slight snugging up, to solve the leak. Use a 1/4" drive, and just tweak them a tad.

That’s my vote...

boat737
01-02-2018, 09:38 PM
Sounds like a plan. I'm on it. Progress report to follow.