Kenworth 3406 cat motor blowing gaskets

Sounds like the liners aren't set up right. Theres almost no reason for them to blow a head gasket unless the gasket was damage during installing besides that its almost always an issue with the liners. Whether they have dropped or set too high/low or just too inconsistent height across the block.

 

I would say that the liner protrusion is low and or uneven across the liners. The fix is to remove all six liners and have the block counterbored to set liner protrusion between 5 and 6 thousands above the spacer plate. Also make sur the spacer plate is in good shape and the bottom of the head is free from fretting where the fire ring seals.

 

How high is the boost going up to? I Found out that the head gasket would not hold over 65 psi. I was pushing 78 and it kept pushing the gasket's out. The liners were set even at 5 high with new spacer plates went through about 8 gasket 4 heads and 6 spacer plates before I turned back the boost to 60

 

Are you using CAT gasket or aftermarket?

 

Well I think you just answered your own question. Way to much boost for the horsepower your making. With lots of boost comes drive pressure or as some people like to call it, back pressure. Really hard on head gaskets.
I think mr haney makes a lot more hp then your pushin and if memory serves me correct he is doing it on 45 psi boost. Don't quote me on that thou, I could be a smidgen off. I do know its no 60psi.

You got to get in touch with Kurt and hang the correct turbo on that thing. A guy can't make any money the rate your going.
I'm sure Kurt will be along shortly to give you some good advise!!
My advise is to take it.
Good luck.

 

Oops, Sorry just responded to the wrong post. Gonna leave it cause it still might help the original post if he indeed does have high boost.

 

Yeah it was higher than kurt. It was also a twin turbo they are stock high boost. and had hi compression pistions in it also but it was funny There were 3 diferent drivers behind the wheel adn when the one driver was driving i knew it was comming back with a blown head gasket.

 

If your makin 80 psi boost that just tells me your turbo is to small and more then likely way out of its map range. Get some specs as to what this turbo is and I'm sure Kurt can tell you what you need. Your intake temps are probably off the charts with that turbo also. Either way it's all bad bud!