603.970 coolant leak at heater outlet fitting
 

My 350sdl is losing coolant at the aluminum fitting in the rear driver side of the aluminum head at a rate of about a 1/2 pint in 300 miles. It's a long story but the theads are stripped. Is there an easy fix out there or does the head have to come off?

The fitting attaches to the head with a fancy circlip. Remove the circlip, easiest to turn it so you pull straight up, pull the fitting out of the head, replace the o-ring. That should do it. The o-ring comes in gray and green. I don't know the difference.

Sixto
87 300D

The o-ring at the water pump is 012 997 51 48. IIRC it's the same o-ring at the back of the head but I can't find the part in EPC.

Sixto
87 300D

Let me know if something gets damaged back there, I pulled that pipe out of my '91's head, it is in the scrap pile.

Thanks guys, but like I said, it's a long story. I know it's not the O Ring, the threads are really stripped in the head and the aluminum plumbing fitting didn't look much better apparently. The Indy who did the work, I found out, put it back in with epoxy but it still leaks. I won't take it back there for obvious reasons.

Why were the threads touched?

Do they make Helicoils that big? Might have to pull the oil filter housing to fix the threads.

Sixto
87 300D