[Healeys] Head Gasket Woes Part Three

[healeyguy at aol.com]

StevenSome thoughts.  Please advise if my assumptions are correct or not. 
Looking at your photos I can offer the following: Anybody have a penny?
AssumptionsThe gasket erosion occurred between cylinders 3 and 4.The erosion of the head material matches the gasket erosion shown in the block and gasket.The head has had machine work done adjacent to the area of head erosion (as shown in the photos) The installed block cylinder sleeves were stock inner and outer diameter.  
Thoughts:The block sleeving and combustion chamber machine work appears to have reduced the sealing area for the gasket crimp.in the area of the erosion.The erosion would appear to have started in number 4 cylinder.That area has one of the larger water galleries in the 100 block, even though it is somewhat squeezed between cylinders 3 and 4. The Payden style gaskets have sometimes failed in non-stock engine builds. That said we run 10.25 to one compression in our 100. 
Since you were able to get reasonable drivability for the first 1500 miles and then added another 1500 miles without reported backfiring through exhaust or intake, It would seem things held together reasonably well until the gasket failed and the head was eroded by the high speed exhaust gases.  Mr Lawrence mentioned bad gaskets producing an overlap of the gasket into the bore. In this case it may not have been the gasket at fault but previous machining on the head and or the size of the sleeves that reduced the gasket crimp..Perry


-----Original Message-----
From: Steven Kingsbury via Healeys <healeys at autox.team.net>
Subject: [Healeys] Head Gasket Woes Part Three

Let me start with a little history with this email. My engine has just a shade under 3,000 miles on it since rebuild. The head was checked for cracks, none found and was ever so slightly shaved to make sure it was completely flat. The machine shop I use builds race engines and they do really good, reliable work.
Then the block was gone through, new sleeves inserted and bored so to fit my new pistons. Again the top of the block was checked and double checked to make sure it was flat and mated to the head.
When I fired this engine up for the first time after rebuild, she lept to life! No turning it over and over and over. She fired right up. I was quite pleased. 
I ran the engine for about twenty minutes at 2,000 RPM, never got above 180 degrees and then took her out on the road. I took care not to over rev, and drove up a long hill in third gear at low RPM to help set the rings. 
I did have some problems with the distributor, but that was fixed and at fifty miles I checked the head again for torque. I drove the car more and retorqued the head again at 150 miles, all was fine.
I checked again at 500 miles and again at 1500 miles. All was fine. 
Anyway, this history is to let you know I think I did everything I could and did everything overly cautious to break this engine in correctly. And this engine was running great! My car was a joy to drive and loved cruising down the freeway at 80 mph! Seventy was a sweet spot and was a joy to drive. 
I'm now thinking of going with the aluminum head thanks to the combined wisdom of this list. Aluminum head with the steel gasket. I've heard nothing but good news about them and I don't want to have that worry/doubt while driving down the road. I am also going to continue down the path of fixing this head as I think it's worth it in the long run. 
I want to thank all of those sending in suggestions and tips and cautionary tales and things to look for and all of the views have led me to believe, bite the bullet and spend the money.
Thank you all and I will report back!
Steven Kingsbury
BN1 
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