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Blown head gasket that cant be good!

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texas_bugeye

texas_bugeye

Jedi Knight
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Well I guess I'm lucky in that it happened about a half block from home and there appears to be no damage to anything else.
10,000+ miles on a low buck gasket. Cant get to upset. I wish I would have known about Payne gaskets before I bulit this thing with a cheapo on sale gasket set $18.00? Now I have an excuse to put the 12G295 on. Anybody know where to find info on the dish cc of this piston.
AE 14396 +.030
 

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Here's a tip from some of the very smart people on the forum gave me. Spray head gasket sealer on that new gasket. It will help prevent future blown head gaskets, but more importantly, when you inevitably remove the head again in the future, the old gasket will peel right off: no need to spend hours of scraping and cleaning.
 
Usually it is written on the top of the piston.
 
I think I'm going to skip the chepo this time and go with a Payne gasket.
It kind of looks as the 1-2 were starting to leak also.

As for the piston it just has the brand PN and size.I have poked around on the web but cant find any info Tech info on the dish displacement.
 
In college in the mid 60s I had a Bugeye that blew a head gasket about every three weeks or so. PO had modified the engine for SCCA events and compression was pretty high as I recall. I bought head gaskets six at a time from JC Whitney as well as tubes of Permatex Fix A Gasket which I applied liberally. Eventually I had a cracked head and block. Found a complete engine in a junk yard which I purchased for $50. A mechanic friend at the local service station installed it with my feeble help for $25.
 
As for finding the piston dish CC volume, this would be easier if the piston was not in the bore, but it can still be done fairly easy. Go to your local drug store, ask for feeding tube syringe (cost a couple of bucks max), it will measure in MLs, same thing as CCs. #4 piston looks nice and steam cleaned thanks to the blown head gasket, so that the one I would use for measuring, fill the feeding tube syringe with liquid, I use that green rubbing alcohol, but there are plenty of things you can use, fill the dish in the piston with the syringe until you top off the dish, record what you have put in the dish, and there ya go, use the syringe to suck back the liquid after the test, wipe the remainder off with paper towell or coffe filter.
 
Thanks for the sugestion I'll give it a try. So the secret is to find a liquid that has a alow sp. so it "lays flat in the dish" alcohol got it. Thanks Hap
I think now will also be a good time to transfer timming mark to a reasonable location. That quick steam clean sure made reading the piston make and part number easy looks like brand new. it looks like 1-2 were ready to let go in the near future also.
 
I've seen people cut a disk of lucite and put it on top of the piston, with holes of course to let the fluid in and air out. That way, no uncertainly about whether the fluid is level or not.

BTW are you sure the head doesn't need to be skimmed for flatness?
 
"BTW are you sure the head doesn't need to be skimmed for flatness?"

I have found that a large flat bastard file (new and straight) passed gently over head from several directions will show high and low spots. If lows aren't large or deep, you can carefully file the entire head evenly until they disappear. Final pass with 150 sandpaper on a flat block will really smooth the finish.

Jim
 
A good, stiff, one-foot metal ruler, and a little light behind it, will show irregularities, too, to a few mils. Just be sure to go over it in two perpendicular directions. As for leveling it, I think I'd let the machine shop do it. At least with me, more chance of getting it right.
 
I'm pretty sure these thing is still flat and its the matchbook paper and tin foil gasket at fault. I will be having my 12G295 head gone thru taking about 2.8MM out of each cylinder bringing it back to about 8 to about 9 to 1 and replace the exhaust seats and checkout the guides and a valve grind. Thats why I'm looking for the c.c. of the dish on the 30 over piston. I will probley have the 2A629 head checked out and skimmed if nesssary cleaned up and shelved just in case. Thanks for the ideas on checking out the head guys.
Now that I have a set of HS2's and the 12G295 going on It should go like a ROCKET! Well maybe not but it will breath a little better maybe a couple of percent increase in Power but hey when your at 971cc anything is a step up.
Thanks again.
 
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