This is what I call a Head Gasket failure

[john8662]

Lost compression in a cylinder on the race truck and had TONS of blowby, I figured I finally busted a piston. The scary part was that there was coolant and oil in the cylinder, that's what had me worried. Got the engine out expecting much worse before fixing this beast.

Haven't seen a head gasket let go like this before, but obviously they can.

http://www.thedieselpageforums.com/photopost/data/504/medium/030901_2122_00_.jpg

Now I need to check the deck and head, I've been having gasket issues on this corner, so I think something isn't 'true'.

[Austid09]

Yea I'd say it blew a head gasket alright! lol better than a busted piston or slung rod its surprising you didnt bust a radiator or hose or something with all that pressure flowing into the water jacket like that.... maybe the radiator cap popped up in time lol

[turbonator]

Lost compression in a cylinder on the race truck and had TONS of blowby, I figured I finally busted a piston. The scary part was that there was coolant and oil in the cylinder, that's what had me worried. Got the engine out expecting much worse before fixing this beast.

Haven't seen a head gasket let go like this before, but obviously they can.

http://www.thedieselpageforums.com/photopost/data/504/medium/030901_2122_00_.jpg

Now I need to check the deck and head, I've been having gasket issues on this corner, so I think something isn't 'true'.

i think that maybe its time to think about fire rings.... we are looking to do our current build with fire rings.... we think it is good insurance for those trouble spots...the only thing is the groov-matic tool from iskedrian is a pretty penny...LOL... we have noticed that same area on many blocks as being the weak link....we finally found a nice clean 6.2l block after buying and tearing apart three other motors....its always one thing or another..... main cracks, deck issues, or starter bolts...LOL and dont forget the guys that never change the oil.....:rolleyes:

[Robyn]

In looking the piccy over well, it sure does look like an issue with the deck/heads (read this as poor clamping)

The ends seem to be the spot that these let go. I have seen more blown gaskets at number 1 and 2 than any other.

Is this one number 7 (LH rear) hard to tell 100% with the angle of the piccy.

Looks like a deck cut is going to be in order ??

Missy

[john8662]

It was a poor clamping force issue.

Both heads has issues with being straight. Both heads have now been milled and re-installed on the engine. I went with the .010" thicker gasket while I was in there and re-installed the head studs. The Block was checked thourally and did not need decking, which saved me a lot of trouble because I wasn't looking forward to disassembling the entire shortblock.

While the heads were off I discovered I was floating exhaust valves on a few holes due to exhaust back pressure due to the amount of boost I'm running. Three valves got replaced, there was a interference issue (obvious on the tops of pistons).The valve spring seat pressure was increased the maximum I could get away with with the stock geometry. Good to 50 psi intake boost now and 70 back pressure on exhaust.

[phantom309]

http://i39.photobucket.com/albums/e157/wtfuashols123/MVC-014S-2.jpg?t=1307065252

here's the piston that let go with my pump cranked up,.

nick