Liquid gasket sealant - selecting the right one

[pcn1]

I'm doing a job soon on my 1998 Mercedes SL, it runs the M104 straight 6 engine.

Task is to remover the metal timing chain cover (a notorious leaking point in the lower corner) replace the lower rubber gasket, and seal the upper vertical surfaces of the cover with sealant. These are machined faces.
Now watching this being done on YouTube from a guy in Canada, he admitted using the wrong sealant first time, and having to re do the job again as it leaked from day 1.
He then suggested a Canadian brand name sealant which I obviously cant buy here, so can anyone recommend a type I should use for this task ?

Smooth metal surfaces, holding back hot engine oil. No pressure, and I cant see there would be any movement concerns between the faces once the bolts are done up.

I'm thinking Loctite Black ticks the boxes unless anyone can offer better choices ?

Cheers

Edited by pcn1 on Friday 2nd July 14:38

[littleredrooster]

pcn1 said:

Smooth metal surfaces, holding back hot engine oil. No pressure, and I cant see there would be any movement concerns between the faces one the bolts are done up.

I'm thinking Loctite Black ticks the boxes unless anyone can offer better choices ?

Cheers

There will be crankcase pressure, surely, and if it's an alloy cover on to a cast iron block, there will be some thermal movements albeit very small.

Sorry but I'm not au fait with modern sealants, my last experience was with one of the Loctite varieties years ago.

[AW111]

I use Toyota Form In Place Gasket (FIPG) sealant for similar jobs.

Black for engine bits (eg sump), orange for gearbox.

[Krikkit]

Loctite 5980 would be my choice. Sticks like st to a blanket.

[Boosted LS1]

A loctite anerobic sealant works without gaskets. If you have a gasket then loctite do a black oil and petrol resistant sealant from Halfords. It's really good on sumps and timing covers.

[Arnold Cunningham]

I choose 5980 too - it's decent, IMVHO.

Annoyingly I put too little on an oil pan last time - so will be redoing it imminently. Gah!

[paintman]

pcn1 said:

I'm doing a job soon on my 1998 Mercedes SL, it runs the M104 straight 6 engine.

Task is to remover the metal timing chain cover (a notorious leaking point in the lower corner) replace the lower rubber gasket, and seal the upper vertical surfaces of the cover with sealant. These are machined faces.
Now watching this being done on YouTube from a guy in Canada, he admitted using the wrong sealant first time, and having to re do the job again as it leaked from day 1.
He then suggested a Canadian brand name sealant which I obviously cant buy here, so can anyone recommend a type I should use for this task ?

Smooth metal surfaces, holding back hot engine oil. No pressure, and I cant see there would be any movement concerns between the faces once the bolts are done up.

I'm thinking Loctite Black ticks the boxes unless anyone can offer better choices ?

Cheers

Edited by pcn1 on Friday 2nd July 14:38

Just order what he used off ebay?

[Krikkit]

Boosted LS1 said:

A loctite anerobic sealant works without gaskets. If you have a gasket then loctite do a black oil and petrol resistant sealant from Halfords. It's really good on sumps and timing covers.

Yep 5980. Used it to seal sumps and cam covers etc for many years. I'm half worried they'll stop making it and I won't find anything as good which is easy to find.

[Boosted LS1]

^ That's the one :-) It's the best of the best imo.

[Arnold Cunningham]

And convenient that Halfords carry it

[stevemcs]

We use the Ford stuff usually what's recommended for the sump's on the 1.6 TDCi engine

[E-bmw]

Granville black has always done well for me.

[bearman68]

Use lots of the Wynns black gasket maker.

Great product - I always use it to seal water pumps while doing cam belt changes, and I used it to seal the sump of my 1.4 tdci fiesta the other day.

Good stuff!!

https://www.ebay.co.uk/itm/122917184935?epid=21032...

[mywifeshusband]

I use Wellseal when building air cooled VW engines. Excellent stuff

[pcn1]

Thanks for the reply's.
Think I'll go with the Loctite black as suggested. I've used the black before on 4x4 diff covers with no problems, and the grey on motorcycle engine case (where water is present).

Never done a timing cover before so its good to ask here first

[donkmeister]

Mercedes do sell a specific RTV sealant at significant cost. When I did the breathers on my M113 I bought it but found it had gone off in the cartridge, so I used black Loctite RTV from Halfords. No problems and it's been a couple of years since I did it.

The key was getting everything spotless first. I used scotchbrite and then brake cleaner to get everything clean first. I did it when I needed an oil change, my thinking was that running it for a few days would mean any scotchbrite dust that had made it into the engine would be suspended in the oil or trapped in the filter. Probably no need to worry about that but it didn't cause me any extra work so...