cracked heads??

[02bigstrokin]

has anyone ever heard of the heads on a lb7 cracking on the intake side? my truck continues to pressurize the coolant system real bad, but doesnt puke antifreeze, doesnt really use any antifreeze, theres no soot in the coolant but it will keep pressure for days if i let it sit. and when it sits the hoses and o0rings get cold it will push by them sometimes. me and travis are both completly stumped on this one, but hes thinking maybe a cracked head on the intake side building pressure but no soot??? any ideas?

 

[KEVINL]

I don't think so anything is possible.

I think the soot on mine was caused by the bad injectors overfueling the engine and the HG let it in the cooling system

I never puked coolant and never had to add any coolant either if my injectors didn't go bad I might still not know because I never payed attention to that

Was the truck ever overheated?

 

[Mike]

I screwed up a couple of times and left my electric fans off. Over heated bad twice. As you mention, mine held pressure and I thought it was loosing coolant but? If I pressurize the cooling system too, well over cap pressure, I don't loose coolant but do loose pressure over a few days. This may be the pressurizing device? I don't know, may have to remove the heads and have them checked for cracks.

Lots of luck to ya'll.

 

[CancerPipe]

I had all the same symptoms and it turned out to be just the gaskets. Just pressure. No soot or lost coolant. If it makes you feel better my machine shop said they have yet to see a bad set of dmax heads. Not that they see a lot, but most of the ones they've seen had been treated pretty bad.

 

[KEVINL]

There is alot of meat between the valves on a Dmax head compared to other engines I have seen.

I don't see a head being cracked unless it was severly overheated.

Once again I think My soot in the coolant tank was due to the bad injectors at the same time as the blown headgaket. I have never heard of soot in the coolant tank besides my truck I just was lucky enough to have two major failures at once

 

[02bigstrokin]

i hope its just a h/g or a lifted cup. the only reason we were thinking maybe a cracked head is because my friend here at the dealer said hes replaced a few that had cracks in them. i know its rare but if its going to happen it will happen to me. but we shall see when the motor comes out.

 

[Trippin]

I have seen a few cracked LB7s.

But only if the engine was really really hot!

Most likely a head gasket or injector cup.

FYI, we pressure check the heads to 60 psi here, just to be sure.

 

[02bigstrokin]

the truck has never been overheated. its never even seen 210. ever. so i hope its not the heads. good to know guy. thanks