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Head stud bubbling oil

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RestoreThemAll

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First start on a new rebuild of a BJ7 stock motor. Noticed oil bubbling out of the rear most stud. I pulled the head to fix a freeze plug and haven't reinstalled yet. Also pulled the stud. The hole is damp. What should I look for? Do I have a problem?

Also, the Bentley manual calls for bronze washers under the steel washers on the studs outside of the valve covers. My BJ7 didn't have any bronze washers. Should I add some? What's the purpose?
 

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YEAH Dale:

I think any good crush-able washer should solve the problem,
 
Keoke, I'm not sure if you can see it in the pic but the bubbles are coming from the threads. So what I don't understand is how a crush washer would help. A washer wouldn't seal around the stud itself. I also don't see where the oil could be coming from. Any thoughts?
 
RestoreThemAll said:
First start on a new rebuild of a BJ7 stock motor. Noticed oil bubbling out of the rear most stud. I pulled the head to fix a freeze plug and haven't reinstalled yet. Also pulled the stud. The hole is damp. What should I look for? Do I have a problem?

Also, the Bentley manual calls for bronze washers under the steel washers on the studs outside of the valve covers. My BJ7 didn't have any bronze washers. Should I add some? What's the purpose?
Click to expand...
Well, you made me look!

I think it's a matter of interpretation; the first engine section ("A") in Bentley's The Complete Official Austin-Healey 100-Six and 3000 1956-1968 assumes the earliest version of the Longbridge 6-cylinder. Subsequent chapters deal with the 6-port ("AA") and later 3000 ("AAA") addendums.

Under A.18, Replacing (the cylinder head)
#2 "...Ensure that a bronze washer is fitted below the steel washer on each stud which passes through the inlet manifold on the left side of the head;"

I've rebuilt many 6-cylinder Healey engines, and certainly at least some of them were previously factory original, and I have never encountered any bronze washers on the head studs. My one (1) opportunity would've been the Longbridge engine that I've posted so many pictures of in the past, but that example had previously been subjected to an Arizona (New Mexico?) high school shop class.

I do not see the need for the sealing washer on a 6-port head (and Jim, your 2-port doesn't have them now either...).

As for the bubbling stud issue, I don't know; it's not near the oil galley, nor the feed-port in the head for the rockershaft (stud's hole depth is about 1", so still >3" of solid cast iron between it and the oil galley). Might've just been a little residual oil left in the threaded bore, and heat expansion forced it out. Only other possibilities are not encouraging (breached gasket, cracked block and/or head) and really remote.

I'd put some thread sealant (like Loctite 518, or similar) and immediately torque it back down.
 
Thanks for the detail Randy. Very helpful!

Here's a video of the bubbling offender. It sure looked, felt, and smelled like oil.
https://www.youtube.com/watch?v=zKlPABKdWCw

The head and block were rebuilt by machinists, and I did use a new head gasket. That is not to say that a problem with the head wasn't missed. I bought another new head gasket for round 2.
 
Personally, I'd just wait it out; if you start getting some real flow/pressure, then you'll have to act! In the meantime, I'd put it through a couple more heat-cycles and see what develops__always a pleasure to fire up a long dormant engine, you never know what you'll find!
 
Cylinder head studs are supposed to be installed finger tight and if you look closely at the thread there is a relief groove cut in the side of the thread . Its purpose is to relieve pressure from oil etc that may be trapped under the stud in the block . If you had studs with no relief grove and the thread sealed 100% in the hole if there was oil/fluid trapped under the stud then under heat expansion something is going to break .
I suspect the oil is just relieving from under the stud under heat expansion .
Like Randy says . Heat cycle it again a couple if times and retorque the head .
 
Thanks guys. I'll put it back together (with new freeze plug) and run it through a few cycles.
 
FWIW I probably do the wrong thing, but when I put my studs back in the block, I use the good ol' copper slip, fair to say nothing has come up yet and I have some 4000+ miles under the belt. When I first started tinkering with the engine, years ago, there was something like a silver grease on the studs - not sure what that was.

:cheers:

Bob
 
I bet that silver was never seize or something like it Bob. I have copper and aluminum. Randy recommended the copper on my spark plug threads. They're slightly worn.
 
BOB uses the good ol' copper slip. Me TOO

However ,it is classified as a hazardous material here in Ca.
Works a treat every where and you can get it from Canada.:applause:
 
There's also a nickel anti-seize, recommended for high-temperature applications.

Moss sells 'Copaslip;' any relation to 'copper slip?'
 
Loctite copper anti seize. Works to 1800 degrees. I didn't use it on my head studs. A very small amount wouldn't be a bad idea. I'd want to make sure that there's no oil in that stud hole first.
 
I've had the oil coming up the threads before. I just ran it as it was and after only a few cycles the oil stopped. I did consider re-sealing, pulling the head etc., but never needed to. I suggest you do the same.
 
RestoreThemAll said:
Loctite copper anti seize. Works to 1800 degrees. I didn't use it on my head studs. A very small amount wouldn't be a bad idea. I'd want to make sure that there's no oil in that stud hole first.
Click to expand...

I have a life times supply and more - I noticed one of my favourite Ground Anchor contractors was using it on the drill string so asked if I could have a jar of some. Next thing I know I have a several gallons of the stuff - if you can measure it in gallons. There are a lot of cars driving around my area that are using it.

:cheers:

Bob
 
I do not see the need for the sealing washer on a 6-port head (and Jim, your 2-port doesn't have them now either...).
Click to expand...

Randy did use anything in place/instead of on the 2-port?

Danny
 
Dandare said:
Randy did use anything in place/instead of on the 2-port?

Danny
Click to expand...
Nope, as stated in post #4: "I do not see the need for the sealing washer on a 6-port head (and Jim, your 2-port doesn't have them now either...)."

I didn't catch that it needed them until I reread that paragraph in the manual (A.18), in response to RTA's comment about bronze washers. If Jim was having any problem without them, it should've been apparent in his initial tuning of the SU carburetors. After as many years as it's been, there would at least been some staining around the base of the nuts (or in the threads) if there were vacuum leaks.

Perhaps the savings grace in our case, was that the engine was primed and painted after being assembled (in some areas, during assembly, as access dictated) and the enamels have provided sealing, if needed?
 
Nope, no problems Randy. This picture was taken 2 years after you built it when I was adding a little more heat shielding to the carbs. No staining around these head studs.
 

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I have been involved with the 2-port heads since the sixties on BMC saloons and can only recall one person saying that he had a vacuum leak from this source...what I can't recall is why!

Danny
 
Healey Nut said:
Cylinder head studs are supposed to be installed finger tight and if you look closely at the thread there is a relief groove cut in the side of the thread . Its purpose is to relieve pressure from oil etc that may be trapped under the stud in the block . If you had studs with no relief grove and the thread sealed 100% in the hole if there was oil/fluid trapped under the stud then under heat expansion something is going to break .
I suspect the oil is just relieving from under the stud under heat expansion .
Like Randy says . Heat cycle it again a couple if times and retorque the head .
Click to expand...
If it's not the oil relieving from under the stud, I would bet on it either being a blown head gasket, or a cracked block or head.
If it is the oil relieving itself then it should stop after a couple of heat cycles and there should not be mutch oil total.

Dan M.
 
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