i just bought a 85 4x4 4speed for $300 the guy said it didn't have compression, got it home and started fixing pices here and there, i believe i need new injector cap o'rings, i will not know if i need new caps or not till i pull them off and clean them up. i'm going to add clear 3/16 fuel line to check for air when i get that far. does anyone sell the o'rings or know what size they are? should i use viton o rings or??? it runs really rough but it sure turns over like it has compression. oh yeah, when i got it it didn't have a line from the filter to the ip..

im not new to diesels but i am only 18 so i have much more to learn

 

Any bearing house or auto parts store should the o rings, and yes, you should get viton, size 111. Most will tell you to get the complete kit, I'm cheap, I didn't. Iirc the kits cost 40/60 $, I spent less than $5, on o rings. Be really carefully getting them off and back on and you should be ok.

By the way, I'm 70 and I still have much to learn.

 

okay, thankyou!

 

I bought a box of these, there's more than you need, but it's still a good price:


Fuel Injector O-Rings:
McMaster-Carr Viton #111 o-rings

 

I got the new o rings installed to find out the return line is cut in half next to the transfer case and the flywheel ring gear is chewed up... I have a livestock show im going to till sunday so ill return working on it come sunday night, I think ill pull start it until I get it running and know I want to put a $30 ring gear on it and spend the 10+ hours pulling and installing the transmission

 

Fixed the return and noticed the coolent was low almost empty... so I was about to fill it and decided to check the oil... what do you know... I drained about 2 gallons of water out of my oil pan... my question is do I pull the motor and pull the heads off ormaybe expect a rebuold or a good 6.9l donor moto?

 

Was it water or coolant? Rain can get into the engine from the hood to cowl seal through the top of the breather. It will pool up there if the seal is bad and seep into the engine.

 

I would just pull the entire engine out being as how you want to replace the flywheel ring gear. It will be easier to work on outside of the truck than inside the frame. I would also recommend ARP head studs as these 6.9s have problems with head gaskets even when they're stock.

 

Sorry, I should have specified it was coolent. Is It probably the head gastkets?

 

It could be cavitation, but there's a better chance it's just head gaskets. I'd pull the heads to check condition before making any decisions. On mine the head gasket damage was obvious:




Of course mine was a compression problem, not coolant.

I wouldn't worry about studs unless you're turboed or plan to add one later. In fact, if you do have a turbo I'd lean even more towards head gasket being your problem.


You may want to run a compression check before disassembling just to narrow it down some and to check the health of the engine.

 

i have thought about doing a compression check but i cant turn the motor over, the ring gear is too chewed up