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engine running for the first time, but problem.

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Jedi Hopeful
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Hi everyone
Well, I started the engine for the first time this evening. It started pretty easily and ran well, but. . . I was horrified to see oil leaking/bubbling from the head/block joint on the distributor side of the engine, pretty well all the way along. The block and head have both been planed and the nuts torqued. Please tell me that this is just a re-torque job? I can't think of anything else I can do and the thought of pulling the engine again isn't worth considering.
Any ideas?
Matthew
 
Hi Matthew,

Sorry for slow posting as I know your concern after all the work. Since you had block and head planed and joined with a new head gasket, I would first re-torque the head bolts to validate the readings are correct. I would then continue the initial run-in of the engine and allow everything to seat and settle before doing any changes.

A while back, a friend had a similar problem that was the result of a failed new head gasket. Since he had originally torqued the head bolts to proper readings, when re-checking after the issue appeared, he noticed a much lower reading from a number of closely-positioned bolts and concluded the gasket must have been faulty and lost some material. Removing the head, the gasket appeared to have no deterioration. However, when replace, the issue disappeared.

Again, my suggestion is to re-check and re-torque the heads and, if no major changes in torque readings from original, continue the break-in.

Good luck,
Ray (64BJ8P1)
 
RAC68 said:
Hi Matthew,

Sorry for slow posting as I know your concern after all the work. Since you had block and head planed and joined with a new head gasket, I would first re-torque the head bolts to validate the readings are correct. I would then continue the initial run-in of the engine and allow everything to seat and settle before doing any changes.

A while back, a friend had a similar problem that was the result of a failed new head gasket. Since he had originally torqued the head bolts to proper readings, when re-checking after the issue appeared, he noticed a much lower reading from a number of closely-positioned bolts and concluded the gasket must have been faulty and lost some material. Removing the head, the gasket appeared to have no deterioration. However, when replace, the issue disappeared.

Again, my suggestion is to re-check and re-torque the heads and, if no major changes in torque readings from original, continue the break-in.

Good luck,
Ray (64BJ8P1)
Click to expand...
Make sure your torque wrench is accurate too. Lots of variances in the wrenches.
 
I'm far from an expert but I believe that there is a torque sequence that must be followed. I do recall rebuilding a six cyl chevy too many years ago and we had the same problem that you're experiencing. It was because we didn't follow the correct bolt sequence.
 
RestoreThemAll said:
I'm far from an expert but I believe that there is a torque sequence that must be followed. I do recall rebuilding a six cyl chevy too many years ago and we had the same problem that you're experiencing. It was because we didn't follow the correct bolt sequence.
Click to expand...
You are correct! There's a sequence that must be followed with the Healey Head studs/bolts.
 
Hi everyone and thanks for the answers.
The gasket came from A H Spares in the UK, not sure of the brand, could have been County. The head nuts were tightened in the correct sequence.
It occurs to me that on that side of the head are just the push rods so the oil seems to be leaking through the gasket from the push rod holes. My understanding is that there is no oil pressure there so I can't really see how this could happen unless the nuts are loose. I haven't had time to check that, but that will be the first thing. If that doesn't work, I think I'll try another, better quality gasket. As you suggest, maybe a Denis Welch.
Cheers
Matthew
 
What about the studs? I know that "super studs" are sold on the premise that they are stronger, and that the old studs stretch. Also, that the threads can be comprimised, or stretched. If the block and head have been shaved by a machinist, and there is no mistake there, and the head gasket is new then what else is there?

What about a compression test? That would tell you if the gasket is failing at the cyclinders. Have you pulled a spark plug to check for any contamination?
 
Run it again get it hot, get ready with your wrenches . Once its hot shut it down pull off the rocker cover and valve train etc and torque it again while its hot . and an extra 5lbs on the torque isn't going to break anything . Try it again and see if that fails then change the head gasket again .
 
FWIW:

Friction can ruin your rebuild and it shows up in many places. Friction can prevent your parts from fitting and prevent your hardware from reaching the proper tension against the parts you are joining, even if you use a torque wrench. I take a number of steps to make sure that my parts fit correctly and that I don't get false readings on my torque wrench due to friction.

You may have done all these things, but here is what I always do if I am not using all new head studs, nuts and washers:

Run a thread chaser or die down every stud to make sure the threads are perfect.
Run a thread chaser or tap into all the nuts to make sure the threads are all perfect.
Replace all the washers to make sure I don't have any burrs on the washers that might dig into the nuts or the face of the head.
Test fit the head to the block on the studs to make sure the head seats on the head with no binding. Slightly bent studs can hang up the head.
Apply a relatively thin lubricant on the stud threads and washer faces to reduce friction. I do this to new hardware as well as reused hardware.
Tighten all the nuts in the correct sequence going first to 50% of full torque, then go around again to 100% and then recheck them all. Make sure you have an accurate torque wrench.
Run the engine to full temp for at least an hour (up to 10 hours), then remove the valve cover and re-torque.

I hope some of this helps.
 
Also, make sure that the thread of the studs do not end before the nut reaches full torque. I once shaved the head far enough that the threads of the stock studs stopped before the nuts reached the face of the washers.
 
I had a problem where oil was leaking past the rocker pedestal studs onto the spark plugs. The threaded holes that the rocker studs screw into go all the way through the head (at least on my original '67 and new aluminum heads). Might check there before taking anything apart.
 
Thanks for the great advice everyone. Legal Bill, I did use new washers and all threads were in very good shape.
I retorqued the head last night and it did appear that the nuts on the r/h side of the engine had lost some torque. I'll try running it again tonight and see if there's any improvement, otherwise I guess it's a new head gasket.
Cheers
Matthew
 
Well, the re-torquing didn't make any difference. Bummer!!! So it looks like I'll have to pull the head at some stage.
Matthew
 
Hi Mathew,

Sorry to hear your results. If I am not mistaken, you are leaking on the pushrod side of the head. Are you sure the oil seepage is not the residual oil that had not escaped during the original run-in? Although a new gasket may be called for, if for nothing else then piece of mind, your issue seems to be on the side of the head that should not have any pressure present to push oil past the gasket. Have you done a compression test to verify consistent pressure in all cylinders? If I could verify consistent compression and no oil in my coolant, I would continue the break-in with the present gasket and see if the seepage continues.

Good luck,
Ray (64BJ8P1)
 
I once had a very similar problem with another restoration of another car, and the problem was that I did not install new studs. Studs tend to stretch themselves and HAVE TO BE REPLACED everytime you rebuild an engine. If you did not install new studs I would do so, as well as a new gasket (your already used one can't be reused) and try. It did work for me.
 
You do not have to replace the studs on an Austin Healey engine when you do a rebuild. In fact, you can rebuild that engine many times with no problems using the original studs.
 
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