thermostat housing gasket - silicon or no?

[romeox929]

as question states, I assume it would be helpful to add a layer between block-gasket and gasket-housing. I haven't noticed any mention to use it at bmwe34.net or bentley manual, so any input on this one would really help out. TIA :help

EDIT: sorry, i have a 1991 525i with a m50 motor.

[FWinNH]

No need. The oring will seal the connection quite nicely. No muss, no fuss...

[calmloki]

Doing the same job on my '93 525iT tomorrow. I don't think BMW uses silicone or gasket sealer much of anywhere. However, I'm going to the not-made by-BMW aluminum casting thermostat housing and don't trust the mating surface to be perfectly flat as BMW parts seem to be, so i will probably use a thin smear between the gasket and the housing, but not against the head. Other thoughts?
Tom Walrod

[632 Regal]

NO SILICONE it corrodes aluminum after time.

if theres an O ring theres no need for anything. if it has paper gaskets use permatex spray gasket or similar.

[FWinNH]

I have the aluminum t-stat covers on both my M50 and M60 engines and both sealed up nicely with just the o-ring (profile type gasket on the 6 cyl).

[calmloki]

Good deal - didn't consider the O-ring for the thermostat. I'll go sans goop.
Tom

[Akhil]

found it was leaking nad had to drain and redo it with t-stat/water pump sealant. I don't know it has silicon or not, but its says "Water Pump/ T-Stat sealant" and safe for entire cooloing system. It cost a $1 only. I won't do t-stat without this sealant after this experince.


Hope this help.
Akhil

[romeox929]

theres an O-ring that goes around the thermostat itself and a separate gasket (paper?) that goes between the housing and the block. I guess permatex wouldn't worsen things, only make better?

[FWinNH]

theres an O-ring that goes around the thermostat itself and a separate gasket (paper?) that goes between the housing and the block. I guess permatex wouldn't worsen things, only make better?

Not on an M50 engine it doesn't. Are you sure you don't have an M20? I thought the 525 in 1991 was an M20.

[romeox929]

Not on an M50 engine it doesn't. Are you sure you don't have an M20? I thought the 525 in 1991 was an M20.

I don't know when they started producing m50's for 525's, but I'm positive I have a M50.