As I am mentally preping to do the head gasket on the 89 300SE, Should I use the loctite 5900 on the block & head, as well as the timing cover & seals?

NO! The OE gaskets have sealant around all needed areas!

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Is there a "rule of thumb" when to use and when not to use the Black MB gasket sealant or Loctite 5900? I never use any sealant on rubber gaskets such as rubber transmission pan gaskets or rubber valve cover gaskets - only torque to spec; but what about other areas?

I however did use sealant on the upper timing covers and around the camshaft position solenoids on my M119 engine.

Should the sealant be used on other gaskets such as water pump gaskets, oil pan gaskets, etc and like?

I'm not a mechanic by trade, but I attempt many DIY projects.

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Russell McMahon
Tulsa, OK
2001 CLK 320
1992 400se
1993 400e
2000 320ML

My thinking is to use the loctite on the exterior edges of the block and head.
This is where the gasket has a tendency to fail and leak continually.......???
Anyone else done this????

Ken, I am thinking the same thing. I am wondering if I can do it as a quick fix.
Where can I buy loctite 5900? Thanks.

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89 300 CE

The sealant is only used for parts that have no gasket, such as the front cover on the M103. Don't use it on the head gasket.

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Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.