Planning on replacing the pre-chamber seals on 85 300D, anyone else done it?
 

I'm planning on replacing the pre-chamber seals on my 300D and I was wondering if anyone has done the same and if there's anything to pay particular attention while doing it. I bought the tools recently so it shouldn't be too hard.
I think I have a leaking seal on #5 cylinder since the compression reading was lower on it than the rest. I've seen some bubbles around the ring when I had a fuel leak on that injector so I'm assuming I need to replace it. I plan on replacing all the seals while I'm at it, if they're not too expensive. I'll also clean and inspect the prechambers at the same time as well.

DJ,

Having been a factory trained MB mechanic for 30 years, I can't think of one good reason to waste the time doing what you plan to do. The little bubbles are normal and have nothing to do with your compression.

Peter

I was thinking the bubbles were indicating some kind of seapage. The compression in cylinder #5 is coincidently nearly 100 PSI less than #1.

Readings were:#1 to #5
380, 380, 380, 340 and 295

If the prechamber seals were the primary cause of that compression values, I think you'd be able to feel and/or hear the combustion gases RACING out of there. If it were me, I'd be double checking valve clearances first.

The values were taken after a correct valve adjustment.