a few years ago I purchased a 292 engine that was running .I noticed it had new head gaskets on it. it ran really good for a couple thousnd miles then wammo,same problem.I ended up putting the project off because of that.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

What heads are you using, and how much were they milled?  Unposted heads and excessive milling can be a problem.  What total ignition timing are you running?  Excessive tiiming can cause excessive cylinder heat.

John - "The Hoosier Hurricane"

on one engine im running unposted G heads that John Mummert prepped for street use.The other has 113 heads.Both engines run 12 degrees intial and 37 total ignition advance.I experience no detonation.On the engine with 113 heads ,it has barely made it 500 miles when this occurred.The one with G heads ran for 5000 miles before complete head gasket failure.Ive had several other Y-blocks over the years and none of them have been able to make it past 5000 miles with out blowing the head gasket.How do you guys make past 5000 miles without blowing head gaskets????These arent race cars they are trucks that we just cruise around in.My race car also does this.It has a 312 with posted G heads done by Mummert.I run that one  hard.IT is usually good for about 5 passes and then it blows.Heads and block are flat.I use studs torqued to spec.Ive tryed every kind of gasket except the steel shim gaskets.Ive got thousnds of dollars in these things and its getting old.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

both heads dont seem to milled excessivly,I can still read the casting letters pretty good on the bottom.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

Don't take this the wrong way, but it sounds like you are the common denominator. Is there anything you do during assembly that may compromise the ability of the gaskets to seal. Maybe any secret tricks you use to gain a performance edge? Maybe the alignment dowels you are using are preventing the head from clamping the gasket properly?

I've used Felpro, and both versions of Best Gasket head gaskets without problems. Blowing head gaskets is not a common problem with a Y Block. If both surfaces are flat and the bolts are installed correctly, and properly torqued, it will not leak.


Lawrenceville, GA

all of these engines run great,with good power .they sound great.my race car is a 55 gasser.Ive been able to get it into the low 13s with a 312 with flat top pistons.I just cant get past the blown head gaskets????????I love y-blocks ,but need help!I took out a real good running 351w to put in a y-block in my truck,now Im kickin myself for it.I cant use the truck anymore because its not reliable.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

yeah,It seems that it only happens to me with y-blocks and not other engines.I dont use any special tricks .Ive been a mechanic for 12 years and dont have any problems with my other Fords.The gaskets seem to blow in random fashion,sometimes in the middle and sometimes on the sides,and sometimes all over.I used new dowels and keep everything clean.I use an old tap to clean the threads out,making sure not to cut any new material out.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

I feel like an idiot,Im stumped on this and until I figure out what Im doing wrong I think I will take a break from Y-blockin.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

In the last 10 years Ive had this happen on 4 other y-blocks that I didnt even assemble.??? what gives ??,does anyone else have these problems??In fact Ive purchased a few other engines that other people were fed up with.they all had blown head gaskets on them when I tore them down.Another guy I know has the same problem.Ive been tryin to talk him out of putting a shevie scrub in the thing.I think hes fed up to.

55 fairlane gasser 312 /c4, 57 f100 292/c4, 52 mainline gasser 302/t10 4speed

I bought my first Y block 45 years ago and still have 3 of them and have put more heads on than I can count and blown head gaskets have never been a problem with them like a 6 cy with the long head. I still remember when the Ford dealership here got their first torque wrench and the old timers didn't use it because they had been "feeling" the torque for years and head gaskets were never an issue. I still think that either your bolt holes aren't deep enough, or your locator dowel holes aren't deep enough. I don't back the bolts off before retigntning, but apparently other guys back them off just to the point where they break loose and have no problems. I just a couple of weeks ago pulled the heads on an engine that I did a quickie valve job on 25 years ago because I am going to replace the engine with one I built and I rather store parts than complete engines. It had no burnt spots on the gasket. I would run a bolt into each hole and make sure it goes in far enough to apply clamping pressure. The bolts should go down easy enough that you can hang an 11/16 box end on them and screw them all the way down with one finger. And scratch around in the locator holes. Ford wouldn't have built y blocks for 10 years if they all had this problem.

Kenneth

Fredricksburg, Texas