Engine/Transmission (1994 - 1998) Head gasket just blows

[Josparkz]

So I'm driving along yesterday, just minding my own business. Well I was kind of in a hurry, so every time I had an opportune moment I punched the throttle.

Keep my good eye on the egt gauge, backed it off as soon as it got to 1300*. No increas in coolant temp.

Got to the stop sign at the end of the canyon and thought that it had got a little chilly in the cab, so i turned up the heater. Got down the road a piece and realized it was blowing cold air. About another mile or two and I notice the coolant temp gauge rapidly climbing. The oil temp did not.

I pull over fairly soon and pop the hood, amidst a great cloud of smoke and the sound of boiling water. I let it cool down and limp on home. It seems that there is a coolant leak on top of the head between 4 & 5 cylinder. .

Best guess so far is I overboosted. :{

 

[Gary - K7GLD]

"Best guess so far is I overboosted"



YUP, the other version of "if ya wanna play, ya gotta PAY!)...

 

[moolie]

how much boost was going to it

 

[Josparkz]

how much boost was going to it

My 35 lb boost gage never seems to go over 32 lbs.

I am starting to suspect the gauge is

pegging at 32, in which case I may have had a bit more.

I need to test the gauge for accuracy. I also need to put a different gauge on the turbo to test it.

I don't think I really want to load up the turbo right now though.

 

[RonA]

How long has it been since you checked the torque on your head bolts?

 

[Jim Fulmer]

I just ran into this issue with a truck, he was running 40-45 psi on a stock turbo with an 18. 5 housing, he's at 450hp on fuel and 500hp with water, the teardown showed the head need . 010 taken off it to make it flat, the gasket wasn't that bad as it was just leaking a little oil but the head bolts had maybe 70-80 lbs of T/Q on them..... not good, the truck has 210K on it and had never been touched... . it's the same truck that I got the 370 spray pattern pic from.



Jim

 

[Joseph Donnelly]

If the leak is on top of the head, just outside the valve cover, you may have a core plug that rotted through. It is metric so you probably won't have much luck at the local parts house.

 

[Jschafer]

Is it a good idea to check and or re-torque the head bolts and if so how much? My truck has 300k on it and I have never touched it either. I have notice other threads talking about blown head gaskets and I guess this is a concern for me.

 

[Bandit1]

dont rule out a small crack in the head, i chased one for a while until it finally showed itself. just a thought

 

[Josparkz]

If the leak is on top of the head, just outside the valve cover, you may have a core plug that rotted through. It is metric so you probably won't have much luck at the local parts house.

Ah yes. The freeze plug up there filled with wet muck Oo. That would be a real relief if that is all it is.

Further testing pending.

Do you happen to know the size?

Thanks.

 

[Josparkz]

Hopefully Intermountain Cummins has those plugs in stock.

 

[Josparkz]

13/16" freeze plugs look like they should work.

Unfortunately, the leak appears to be coming from the bolt that is in the center of the valve covers, between 3 & 4 cylinder.

Time to start tearing stuff apart. :{

 

[TrqMonster]

I had head gasket issues a few months ago. Like said previously, gotta pay to play. I had been leaking around 4 and 5 for awhile and it wasnt that bad. Towing a jeep, screwing around = too much and cylinder #2 went to atmosphere thankfully so I could get home after adding lots of coolant. I had been getting about 45 PSI out of the stock turbo and I knew I would be upgrading turbos soon so I had it fireringed and 12mm studs installed when gasket got fixed. Now I have read that 12mm studs may not have sufficient holding power. Guess I will put that to the test when it gets warmer and I start pushing the boost with the new turbo that goes on tommorow.



What I really wanted to say was I had the head checked for cracks and it was fine. The block was flat and the head needed just little shaved off. Didnt cost much and nice insurance that at least when it went back on it wasnt cracked and was flat. Also, to help avoid future issues you might consider o-ringing, fire-ring, studs depending on what you decide. I had fire-ringing done and have heard from somebody that it may not be that beneficial and also that the 12mm studs may not hold. So research wisely I guess.

 

[Josparkz]

The o-ringing and fire-ringing technology doesn't seem to have gotten to Utah yet .

A fellow down in Texas has a head gasket he is working on with a special fire-ring that needs no machining.

I may be the alpha tester for that , the way things are going .

Of course, there are some really nice heads sitting in a shop up in Canada