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I got the 6.2 blues

RNation said:
and I changed the oil right before I took the heads off, actually thats how I found the original proble was when I was changing oil and checking coolant and I discovered oil in radiator
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Oooh. Bad. Should change the oil right after. I GUARANTEE Water got into the oil during Head R and R. Now onto the oil in the rad. You are saying after replacing both HG's and flushing the cooling system and installing a new rad that you now have ALOT of oil in the coolant AGAIN. I doubt not milling the heads is your issue if the machine shop checked them. Milling is generally done if there is warpage and if they checked and magnafluxed them I'm gonna assume the checked the plane on them. I would do what I said at this point pressurizine it and start with the oil coooler lines removed. If you get no evidence of pressure out of the oil cooling lines while the rad is pressurized then unfortunaley you need to move onto the engine. Also while your oil cooler lines are disconnected and you are pressurized check the lines as well for pressure. It may be worth while to have the engine heater plugged in and motor warm while doing this . It's gotta be going somewhere. Somewhere there is a breach between Oil and coolant. By pressurizing the coolant hopefully you will push back out whereever this breach is. Remember that while you are pressurizing the cooling system, the engine Oil pressure is zero so it should pusyh back whereever the breach is.
 
ok, I'm going to stop by harbor freight hopefully tommorrow and check that out. How do I check the oil cooler lines though while disconnected?
 
Look for antifreeze coming out of them when you pressurize it although you may see oil first. Nothing should come out other than some draining a little but if all of a sudden when you pressurize the system oil or antifreeze or both start pushing out the oil lines your problem is in the engine and that is bad. I'm not exactly sure where else in the motor you could get a breach that would push oil into the antifreeze more vs Antifreeze into the oil. Pressure diff is about 20 lbs or more. Ave Oil Press is 40 psi(I know some have more some have less) Avg cooling syst pressure should not exceed what ever your rad cap is rated at. I would say no more than 20 psi max. So for the oil to enter the coolant somewhere in the Oil pressure circut is where it has to be. If it was just a crack in the block or water jacket antifreeze would enter the engine not vice vs especially since these engines(stock) run neg pressure in the crankcase due to CDR system. Hopefully your problem is either residual or another bad rad.
 
Acesneights1 said:
Studs are the preferred method with intruck head jobs as TTY bolts can't really be properly torqued in vehichle.
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Not sure what you're talking about. I never had a problem torquing head bolts in a truck.
RNation said:
With the heads I did use new bolts but the heads weren't milled which is bad right?
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GM doesn't reccomend decking these heads. Anytime you have them off, you should take a long straight edge ( i use a steel rule ) and check for warpage. The limit is .003" warpage long ways down the head. There is another spec for measuring across the heads but i don't remember what it is for sure. If the head warpage checks out, put a new gasket on the block and put your head on and torque it down.

The can be decked, but you will need to run a thicker than stock head gasket to accomidate for the lost head material. Precup cracks are common and are ok so long as they don't run past the point of the fire ring on the head gasket.
 
I pressurized the cooling system to around 20 psi, it gradually lost pressure. It took probably 2 min. to go from 20 to 15 psi, then I unhooked it. I didn't notice any water or water bubbles in any of the head bolts and the oil cooler lines were not leaking anything on the ends. I did notice a decent amount of water sitting in the heads though.

Someone mentioned to me that the oil and coolant cross paths in the lifter bores in the block, any insight on that?

I'm getting kind of discouraged here because the problem seems hard to find, I'm not sure if I should maybe just go with a re-built one or keep on trying to figure this one out. The thing that sucks is that this is my work truck so I'm using the wifes truck for now.
 
Another thing I noticed is that while taking the intake and VC's off all the bolts and studs to them weren't very tight at all. I know we tightened them up real good but they seemed to loosen on their own. Maybe the head bolts did the same? I'll have to check.
 
Headbolts should not loosen up. If it's dropping pressure like that it's going somewhere. Pulling the Oil pan down unfortunatly maybe the next step. You saw water in the heads but didn't see it coming from any of the head bolts huh ? Too bad, that would have been easy fix. either the head or the block is cracked I would say at this point. I suppose a lifter bore could be cracked. Hard to see down there. Not like a gasser where the valley is open. If you drop the oil pan may see it dripping down or maybe pull the lifters. Like you said it maybe time to consider how much more time you want to spend on it since at this point it will probably be bad.
 
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randomid25 said:
Not sure what you're talking about. I never had a problem torquing head bolts in a truck.


.
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TTY bolts are supposed to be turned in 90 degree increments and there it virtually no way to do that on some of them. That said i did it by doing it in 2 shots but that is not the right way and Bill Heath was the one who expalined why doing that is bad and why Studs are the way to go in truck.
 
So the oil pan bolts to the bottom of the block? And by dropping the oil pan I could pressurize the system again and see if waters dripping down right? (or maybe)

Another thing that confuses me is that before I took the heads off the cooling system must have been fine (as far as leaking) because when we discovered the oil in it, it was still full at least, so after we put the heads back on is when the coolant started disappearing. It did get hot a few times after we putt the heads back on. The hottest it got though was about 240f which I don't know if thats hot enough to crack anything or not.
 
I'm trying to think how you'd end up with a lot of coolant pooled under the valve covers. I can only think of two ways... either coming up from the water jacket around a leaking bolt, or condensation after being steamed out of the crankcase.

[EDIT: Or a cracked head... ouch.]

After my block cracked, I found all kinds of rust later on the inside of the VC from all the water vapor collecting there. But not much below the rockers at all. How much water did you say you were seeing on your dipstick?

I'm thinking that if it's a coolant leak to the outside world or the crankcase (has to be one of the two if you're losing water from the rad, right?), then maybe taking the radiator and heater core out of the loop and pressurizing the block's coolant passages with something like 40 - 60 psi of air might allow you to hear the leak, as well as hunt for it with soap solution. Is there anything that might be harmed in the system from that kind of pressure? I don't think you'd pop the freeze plugs, but I don't know for certain.
 
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240 is WAYYYY to Hot. Catastrphic engine damage hot. Anything over 210=BAD. I'd start looking for a motor. Yeah if you wanna continue diagnosis, drop the pan and pressurize and see if coolant starts dripping out of anywhere. It might be wirth mopping uop the water in the valve area real good and then repressurizing again and letting it sit for awhile and see if more water "appears". MAybe even overnight.
 
Theres a decent amount of water bubbles in the heads now just sitting right by the rockers.

I'm not sure where to connect a pressurizer to the block so I could check for leaking that way. The heater core is out of the loop though, it went bad the other day ( I think from flushing out the cooling system after putting the heads back on). But if you think testing the block in that manner would be worth a try i'll do it.
 
Yes by the head bolts, but I will double check tommorrow. Well I appreciate all the help but I think I will start looking for another motor. Because I'm too much time and money into this.

Would you guys happen to know anywhere to get a good re-built motor? I've seen Diesel Depot talked about in here a few times but I'm having a hard time getting ahold of the guy there.
 
Peninsular is the best, but you'll pay. If it's coming up by the headbolts you could ttry resealing them. Got nothing to lose. Do them one at a time. Were the bolts you used TTY ? Did you follow the directions to install them properly ?
 
I would assume they were were TTY, I bought them from O'reillys. They also had some orange stuff on the ends I guess was probably the sealant you were talking about before. We did torque them down in the right pattern and we did it in 3 passes. I think 30fp then 60fp then 100fp or whatever the final fp was supposed to be.

I will try to re-do them though. But if that did work, how would I get the water out of oil system?
 
Acesneights1 said:
TTY bolts are supposed to be turned in 90 degree increments and there it virtually no way to do that on some of them. That said i did it by doing it in 2 shots but that is not the right way and Bill Heath was the one who expalined why doing that is bad and why Studs are the way to go in truck.
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Must be a problem with the new body style trucks. I did my 83 6.2 to spec without having a problem.
 
RNation said:
I will try to re-do them though. But if that did work, how would I get the water out of oil system?
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Sounds like you got the right bolts.

I'd wait to retorque them until you have exhausted attempts to locate the source of the leak.

So by "bubbles of water", you mean beads of (green?) coolant sitting on top of the residual oil by the headbolts? That's a fair amount of water if so, and I'd think that Aces suggestion of cleaning out the oil and water really well, then repressurizing the cooling system would be the way to go. If you get more water collecting there, but still can't find it's source, then try pressurizing the system with air (bypass the rad and heater core first), and use soap solution first around the bolts, then moving on to other areas.

The good news is that if the water is seeping into the oil up top under the VC's, it MIGHT not be seeping into the crankcase from a crack in the block. And you'd MUCH rather have a leaking bolt or even a cracked head than a cracked block.

I wouldn't give up on it quite yet.

There are Humvee takeout motors available from several places for less than 1000 clams. Lots of govt motors in Ohio. For a decent commercially rebuilt motor, you're prob going to be looking at $3k plus... even if you rebuild the one you have. How old are your pump and injectors?
 
Are you seeing the coolant on both sides or only one side of the motor ? The process you described is NOT how TTY bolts are torqued. They should come with instructions but basically you get them all to a torque(50ft/lbs ??) and then do a serious of 90 degree turns past that torque rating which in my Suburban was near impossible to do on a few of the rear bolts. I got this funny feeling you did not install the bolts properly.
 
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