Got the '87 running with a new IP, Runs good....with no water in cooling system. Well, filled with water and cranked her up to bleed the system so she can run more than a minute a day. Was running good, Still smoking of burnt diesel but the IP is supposedly "turned up some" so I ignore it.
"Engine" light was on but I had the oil sensor off with a mech gauge showing 45 psi of oil pressure while dash showed 0. She suddenly stopped smoking but was still purring away at a light rough idle.
She hasn't been run in at least 8 years, maybe more. Tags expired 10 years ago. So I figured the injectors are working free finally. Then suddenly she just shut down like I pulled the key. Thought I was out of fuel so I checked the can and was low but still had enough.

Heres where YOU F#$%#ING IDIOT! part comes in;
Thinking she just hit an air pocket in the fuel line, I hit the key to crank her again....She tried then "CLUNK!" and that was that. Hydrolocked. While she was running, I checked oil level and color, off color but also had old oil circulating through filter, blowby from dipstick and oil filler neck but I ignored it figuring it'll pass, Just junk burning off.

Left rad cap off and looked for combustion bubbles, Nothing. Checked everything. Pulled all 8 GPs and spun it over with the starter. #5 started just GUSHING water out like a geyser. Got it all out and went inside. Cranked it again about an hour or two later and 5 was full AGAIN! I hadn't touched it since I got the water out yet 5 filled back up....

Headgasket would show bubbling coolant, milky oil, sweet smelling exhaust...Not this one. So I don't think its that. I don't have a compression gauge strong enough for diesel engines. But none of the symptoms were there anyway. It's either Cavatation or head problem.
Now, She runs fine with no water in cooling system...Just blowby.

After 5 gushed again, I pulled the bottom rad hose and brown water poured out but I expected that after looking into heater core fitting on waterpump and this engine did sit idle for years.

Before this, There was no signs or symptoms of an issue anywhere. How heavy are these heads? Where I have to work is just dirt. No pavement or shop of any kind. I made a "shop" out of a 10'X10' canopy from walmart and 3 tarps from harbor freight just to give you an idea.

What should my next move be? This engine already looks rough as it is.

 

Pull the head first, will tell you where the problem is. Im thinking headgasket

 

Yup; that much water is /not/ cavitation.

BTW, a sheet of heavy plywood or two can support a cherry picker(engine hoist) if you need to pull the motor.

I just pulled and reinstalled the motor to change my headgaskets in my 88 last weekend, it took me all of 2 1/2 days to get it back on the road. But by now, I'm getting good at that sort of thing...

 

Last head job I did was on a m998 which has the gm 6.5 which is detuned down to 6.2 and that was 7 years ago....would it be possible to pull the heads and leave the block in place?

 

What are the chances a rod was bent? Since I'm replacing the cab, The fenders have to come off so I may just pull the heads instead of the whole block. Why divorce the trans and go through all that hell if its just a head gasket? Now, If it is cavatation, Then obviously it has to come out.

 

if you are pulling the fenders, leave the engine in frame and pull the head.
i really doubt it bent a rod.
as for how heavy the head is, it will be the same as the 6.5 GM, around 110 lbs

 

My thoughts exactly. I spun her twice now by starter since and flys to the moon just as easy with no vibration. Here in a little bit, I'm going to check the oil, if it looks good I'll put the GPs back in and try to fire it off with no water in it so I can at least move her under her own power and to make sure it still runs and if it does, How well....Which is relative because of how long it sat un ran the injectors were kinda sticky when this happened.
110 lbs isn't that bad. Hell, two guys, a chain and some bolts could lift it.
Ask me how I know....

IF it is the HG and I hope it is, since I want to put a turbo on this engine later on, I was thinking ARP studs and fel-pro gaskets. I'm researching into it. Should I have a shop check the head(s) to make sure everything is fine because 5 filling up on its own is kind of disturbing....And how the failure happened, and then the amount of water.....Hell, This may turn out to be a restoration on the truck and build on the engine...

 

Justin at R&D is testing some head gaskets he had custom made in europe rite now on his 500 HP 7.3 build.
if you are pulling it, might as well go with studs.
pretty much any head you send out to have checked is going to come back with reports of cracks in the pre-cup area.
but having the heads checked while they are off is still a good idea.

 

Pulling heads is a pita so experimental stuff may not be a good idea at this time. What all would I have a machine shop look for?

 

cracks mainly.

 

Here's what I would do:
As it's only the driver's side, you should be able to do that with it in the truck.
I did it, but you really need a second set of helping hands.

Don't worry about any machine work, just yank the head. If it looks OK, it's fine. You can see any cracks once you clean it off.

In order to get it clear, you'll probably need to remove half the AC box. It's not hard; just a few screws. There is 1 bolt that has a nut from the inside of the cab; and you can get to it easily enough from the passenger's side foot well.

Don't give up, don't do too much now. For $50 and a couple of days work, you can probably have it running again.

 

mac, he is pulling the cab off to replace it, so it would be a lot easier to just wait until the cab and nose are off to pull the head.

 

Yes.

I saw this post in the other topic:
If he pulls the cab, great. Otherwise, he can get to that head if he needs to with no major tools or money.

 

Not pulling the cab until I get another one to replace it with. Not getting the replacement until this POS runs for more than 5 minutes at a time. Probably won't do the studs after all, Just get normal head bolts for now. Can't do 400 when I still need a core and cab replacement aswell.

 

oh ok. i thought you already had the replacement cab.