Pulling my hair out! Please help before it goes to the scrapper.

[Menniss]

So Im so tired of throwing good money after bad. If I cant figure out this troubling issue the truck is going to the scrapper. So let me fill you all in.

It's an 84 CUCV. I replaced the motor almost 125k ago with a used Hmmv motor from ted's trucks. About 4 months ago I did the head gaskets, replaced the injectors, radiator, all hoses and glow plugs and cpr valve.
She was driving fine until about two weeks ago. I noticed she was running a little hot and checked my radiator fluid. it was very low and i topped it off. I looked over the motor to see as to where it could be coming from. No apparent leaks could be found.

BUT, I noticed milky film around the oil fill lip. removed the cap and there it was, crankcase back pressure. I checked the oil dipstick and found milky oil there too.

now Im not a diesel expert and started scratching my head. asking myself....what could it be? i crossed off head gasket as they were just done, no water out the exhaust and no extreme pressure on the radiator hoses.

So I took it to the guys who did my head gaskets. they immediately suspected my timing chain cover. So I agreed and let the work commence.
I picked the truck up on Friday and was in a hurry to get home before the storm. I failed to check for residual back pressure.

I drove the truck the Saturday to/from work. I noticed that she ran quieter and started easier. Sunday she didnt move and today I drove her around all day running errands. Late afternoon I noticed she was running a bit noisier, then I realized my feet werent warm. I immediately pulled over and checked the radiator. you guessed it....LOW! I topped her off and got my ass home. checked the oil fill and the pressure was back, oil milky.
I called the mechanic and he thinks its a bad block, most likely cracked. So tomorrow he is going to pull the oil pan, charge the cooling system and see if he can spot a water leak.

Do you all have any ideas as to what it might be? I love my truck and its my daily driver. I just cant afford to keep repairing it. nor do I have the time to do it myself.

Please advise.....

 

[Warthog]

He should be able to do a radiator leakdown test to help pinpoint the leak.

 

[chevyCUCV]

HAHA same post on 3 different sites

Think the block ended up being cracked

 

[Warthog]

That would do it.

 

[gimpyrobb]

Good to see he follows up on his posts here!

 

[doghead]

Funny thing is, the CDR valve is SUPPOSED to create a base pressure.

I personally would guess the shop that did the head gaskets either did not do a good job, or use sealant on the head bolts, or the heads had cracks(between valves( and they did not check them.

As for lack of follow up, the OP does not have his state listed(rule) and is fairly new. In most cases like this, I simply take that all into consideration and do not reply.

 

[wayne pick]

Or didn't install new head bolts. They can strech and break over time after being re torqued.

 

[engineman2]

^ That is correct. The 6.2 diesel uses torque to yield head bolts which must be replaced each time the head is removed.

 

[PeterD]

... i crossed off head gasket as they were just done, ...

The head gaskets would be my first point of suspicion especially as they were recently replaced. Of course you could have a cracked head, or other leakage too, but those head gaskets would be very high on my suspect list.

 

[Recovry4x4]

I'd request a rundown of what was done to the heads. I suspect cracked heads or bad gaskets.

 

[jaxsof]

They warp, too (the heads, not, well, some members do too)

 

[rickf]

You know darn well that if it is the same mechanic that is checking for block leaks that did the head gaskets then he already knows what is leaking and he is not going to admit he screwed up. I would also vote for head related, more specifically head gasket repair related hence the reason he is not gonna say anything. "Oh man. sorry but we found the block is cracked. You want another opinion? yea, OK, well, er, but, um............................................."

 

[wayne pick]

Good point by rickf, An inexperienced mechanic will perform the repair as if it were a gasser. Just slapping gaskets on it witthout determining what caused it to fail in the first place. Putting bad heads on new gaskets doesn't accomplish anything. If it were me, I would either get the heads magnafluxed and machined including a valve job, or get reconditioned heads including ARP head bolts and the proper thickness gaskets. It's an expensive job labor wise, if it's not done right it's just wasted money. I would defenetly not bring it back to the same guy that F***ed it up the first time.

 

[overlordofmars]

Before I got into the military vehicle collecting I ran a fleet of trucks for a utility company. We had 25 GMC trucks all powered by 6.2 diesel engines. 9 times out of ten when it was overheating and we had to replace the head gaskets we would send the heads out to be checked for cracks. Almost half were rejected for cracks. Only two times did we find a cracked block, and both times it was between two rear cylinders.. If the job was done right, which I doubt, you most likely have a cracked head.

 

[cajun666]

They warp, too (the heads, not, well, some members do too)

same

get new guy to work on it cause old one does now what it doing