blown head gasket (third time)
 

Hello!

Nice forum, im from chile!
Well, i have a Lo5 engine 2 bolts, speed pro l2256f .40 bore (9,8 to 1 i think), mild edelbrock cam, intake summit, carb edel 1406 custom headers, fully balanced (153 tooth flywheel) stock cams (now im gonna port it just a little).
It really works fine when it works :) (not super powerfull, but it revs fast, very fast up to 5500)

My problem is that i have blown head gasket 3 times (1500KM)... (im a little tired from changing the heavy heads :) )
I use victor reinz 1178vc (there are not more alternatives in my country, but i can get another from summit).

Well i think the assembly was right, cleaned the holes, heads shaved, new standart chevy bolts, head bolts to 25-45-65 Helical Sequence (info from http://www.torkspec.com/torkspecme.a...-5.7L-350ci-V8).

The gaskets blows when i push the pedal up to the radiator :) (heavy load too many times).

Any clues?:huh:
Maybe the gaskets are not the best for my app?

las time after the blows, i checked the torque and it was fine (before i removed the heads).

Im very lost!! :(

thanks
Chris

Re: blown head gasket (third time)
 

Im assuming these are iron heads?

When you had them off did you have a machine shop magnaflux them to check for cracks? They cant always be seen with the naked eye

Re: blown head gasket (third time)
 

hello!
Yes, iron heads, not magnaflux, but one time was the right head and then the left head, so i believe that is not a crack. one head cracked...can be...but both? I dont believe i have so bad luck...
The only machinist that i know that magnafluxes its very very expensive. (%#" too much!)
Its easier to get some other heads... i fact im trying to get some vortecs! (the search continues) :)
thanks
C

Re: blown head gasket (third time)
 

Exactly where do they blow?

Re: blown head gasket (third time)
 

Could be lots of things. Low fuel PSI or to much timing. Cracked/warped, head/block...

Re: blown head gasket (third time)
 

one time between cyl 6-8, next time cyl 5-7.
maybe advance as sugested?

saludos
Chris

Re: blown head gasket (third time)
 

mmhhh. im going to deck the block and the heads.
Better to be safe...

thanks
C

Re: blown head gasket (third time)
 

i would bring the heads to a machine shop and make sure they are not warped or cracked. also, don't reuse the old head bolts, they tend to stretch after going in and out a few times. and for added security, go with head stud's, they tend to be stronger.

that said checking everything else wouldn't hurt.

Re: blown head gasket (third time)
 

im bringing the block and heads to the machine shop asap...
thanks
C