sealing compound for 116 and 117 engines - PeachParts Mercedes-Benz Forum

GregZ · #1 08-17-2011, 12:03 AM

Hi All,

This is regarding a 117.968 560 engine:

What kind of "sealing compound"is best to use on the front timing cover and on the end cover? The manual only says "sealing compound". I had bad luck before with just using silicone. What is recommended?

Also, the upper oil pan to engine block gasket. The manual does not mention a sealing compound there. What would be though safe to use?

Thanks,

Greg

Ivanerrol · #2 08-17-2011, 12:07 AM

Hylomar.

Everything else will leak after a certain time.

GregZ · #3 08-17-2011, 12:15 PM

Well, a Jaguar XJS enthusiast assembled a long book of knowledge from other enthusiast. There it is stated that hylomar is a "gasket dressing" to be used only in conjunction with paper-type gaskets. They mention that it will be blown out from between two metal surfaces (such as the timing cover to engine block surface) that do not have a solid gasket between them.
They mention Loctite 518 or Permatex 51813 (which is supposedly the exact same thing as Loctite owns Permatex).

Any sharing of long term experience would be welcome.

Thanks!

Strife · #4 08-17-2011, 11:51 PM

I have to do this also, and what has been recommended to me is Hylomar "blue racing formula" (they may make other stuff for paper gaskets); it's used on the nose pieces of superchargers, which had better not leak at all during their lifetimes and/or between bearing rebuilds. I think that this material is polyester-based and very different chemically from RTV. Note that this type of stuff is not designed to fill large gaps/voids - it's designed for machined metal to machined metal interfaces ONLY - no paper or rubber gaskets involved. And- a little goes a long way.

My first experience with this type of material was on the cam cover of the nasty little GM Brazillian 4-cyl engine of the 1980's, and it really didn't leak when applied properly. It is expensive stuff, though, and reading the directions is important.

Dubyagee · #5 08-17-2011, 11:55 PM

Loctite 510 anaerobic sealant

Strife · #6 08-17-2011, 11:59 PM

Quote:

Originally Posted by GregZ

Also, the upper oil pan to engine block gasket. The manual does not mention a sealing compound there. What would be though safe to use?

The oil pan sealing flange and the block are machined aluminum (or iron). The gasket supplied is coated with graphite, and I don't think that any sealant is needed, assuming that those machined surfaces haven't been damaged.

I would not ever get RTV anywhere NEAR a 116/117 engine. I found bits of definitely non-MB RTV in the oiling tubes for the cam bearings of my 380 engine. Keep in mind that all the oil in the entire engine goes through those tiny holes in those tubes and if even ONE gets plugged, you will have big troubles. I did.

People have said that it's very difficult to get the intake manifold sealed without RTV, and yet, others have done it with old -school sticky "gasket dressing" or "gaskacinch". After this experience, I'm going with the gaskacinch.