Oil Leak from Frontmost Valve Cover Bolt

[tarheel]

My 1969 280 SL has been leaking about a tablespoon of oil from the frontmost bolt of valve cover for some time.  Oddly no leaks out of the other 2 bolts for valve cover.

I purchased a new copper washer thinking that would improve the seal.  I don't want to over torque it, but it is definitely snug.

Yet she still leaks!

Should I try a perfluoroelastomer (viton) type seal? 

Please help me as I'm a new owner and also new to this forum.

[Shvegel]

It is a good thing you didn't just crank it down.  The hoops that go around the cam where those bolts attach are known to pull in and strike the cam if you tighten them too much.  There may be an issue with either the bolt being miss-machined or the valve cover being scratched at the seat of the washer.  I would either use a dab of sealant or try an aluminum washer.  Regardless,  I wouldn't tighten it down without a torque wrench handy.

[enochbell]

Make sure to use the correct washer.  It is not a simple crush washer, rather, it is a copper ring seal that deforms under the light torque of the valve cover bolt.  As Shvegel cautions, do not over tighten these bolts or you will risk deforming the bolt towers causing them to collide with the cams.  I would not use any sealant, however.  That seems like cheating 

g

[Benz Dr.]

I had the same problem once but it wasn't leaking from around the cover screw. It ended up being one of the rivets that hold the baffle in place inside the valve cover. I used some epoxy to seal it up and it's been good ever since.

[wwheeler]

Might also want to check the aluminum face that the seal ring sits on. If there is even the slightest mark, it could allow oil to seep. You can use a fine file to CAREFULLY file it flat. I think I remember the torque was something like 8 Ft. lbs. So ,yes very light. I have always used a hollow seal ring that the Classic Center sells and possibly others.