Exhaust-Side Oil Leak

[opus10583]

Hi,

Having "finally" resolved the mid-range miss, I've uncovered another weak link...

After a long overdue and spirited run we've developed an oil leak onto the exhaust manifold, right at the forward upper manifold stud:

1) If the stud is leaking, would oil appear at the top of the manifold flange?

2) Looking to snug a weak seal, I discovered the head threads for the outboard forward exhaust cambox bolt are "done", is this an area that will accept a thread insert, eg any water passage to consider?

Thanks,
Mark

[Kevin1]

No water, only oil behind that stud. The head is aluminum and can take a helical or time-sert thread repair. High temp thread sealant on the new stud will help prevent future leaks.

[opus10583]

Thanks Kevin!

I've the two concerns though:

I can't see how the stud leaking would manifest as oil seeping out the top of the flange, but nothing can surprise me with this car at this point.

The stripped threads are not the stud mount but rather the outside forward-most cam box bolt's receptor in the head.

Thanks again,
Mark

[aj81spider]

It's a long shot, but I had oil there that I thought was coming from the stud and it turned out it was the cam seal. Check the back of your exhaust cam pulley - if it has any oil it's most likely the cam seal. If it's dry then ignore this post!

You didn't mention oil sprayed everywhere else, so if it is the cam seal it's probably not a huge leak. As mine got bigger the cam pulley threw oil all over, including the bottom of the hood.

[opus10583]

Hi A.J.,

No, not sprayed, I'll look closely but the seal should be <1k miles. Oil's fairly well confined to the block, surely leaking stud, but the loose cambox bolt and oil on the top of the flange and above the studnut have me considering alternate realities.

Thanks!

Mark