First of all I'm new to the forum and would like to say hello.Also would like to thank the people at peachparts (Roy,Phil) for pointing me in this direction.I have a 1996 300sd,it recently overheated due to a bad fan clutch,when we got it home the water pump started leaking while sitting in the shop.I replaced then fan clutch and the water pump,cured the overheating,as far as I know,still haven't driven it yet.After doing the repairs I noticed a ticking noise in the intake area,upon further checking I found a leak coming from around the #3 injector,no fuel,just compression.It sounds like an exhaust leak.I just received new heat sheilds today and I am going to change the #3 tomorrow sometime.Any thoughts or suggestions,anyone else ever have this problem or something like it?All thoughts,comments,and suggestions will be greatly appreciated. Thanks

If a new injector heat shield doesn't stop the leak, the pre-combustion chamber might be leaking at the flange where it contacts the cylinder head. You'll need a special socket to remove the ring holding the chamber. In either case, make sure you thoroughly clean the mating surfaces and use a torque wrench to tighten things properly. I used some high temperature RTV silicone when I re-installed the pre-combustion chambers.

Thank you for the reply and advice,I removed everything down to the head assembly and cleaned everything with brass wire brushes,then reassembled everything(I used a thin coat of high temp copper RTV on the seat,shoulder,and in the alignment groove of the chamber)I tightened everything to spec and let it sit about 18 hours,when I started the car today my problem was cured!! Thanks again for your time and advice.