So what is the recommended sealant to ensure a leak-free engine? I'd like to get the right stuff to seal the front cover on my 603.

Thanks

__________________
Chief

1991 350SD

I use Permatex Ultragray RTV.

Sixto
87 300D

The Much Vaunted FSM calls for an Anaerobic (Cures in the absence of Oxygen)Sealant.
(It's the equivalent of Permatex 574)
with a couple of dabs of what they call "Black Omni" in another location.[which is another Permatex Product only it's an RTV.]

[The Anaerobic sealant adds "Strength" to the Bond between the Aluminum T.C. and the Ferrous Block.]

__________________
'84 300SD sold
124.128

I remember using an anaerobic on my M103 front cover years ago, but it leaked again after a couple years. I hate RTV, as it always seems to migrate.

__________________
Chief

1991 350SD

I've been successfully using something called Ultra Copper for years without any issues as long as you do not apply too much.

__________________
Jim

Here's the stuff:



I use it for the EGR exhaust plate as well.

LOL. "front timing cover" as if there were a rear one.

I have used Aviation sealant on nearly everything over the years with good success. The last few years I have used a (Permatex?) product called "Great Stuff" maybe? It is super strong RTV product that has not leaked for me yet. I have used it on a variety of things on our race cars and sometimes have difficulty getting it back apart. This is a good problem to have.

Best of luck and I hope you have a sense of humour.

__________________
85 300D 3 pedal. Current project.
83 300TD (need rear wiper assembly dead or alive)
84 300SD Daily driver
85 300TD almost 400k miles and driven daily.
98 E300D *sold
86 300SDL *sold and made flawless 10 hour journey to new home.