Thermostat Gasket Sealer

[62cruiserinc]

I have a 1981 Mercruiser 260 with a 5.7L V8 (Edelbrock 4-barrel).

As per previous suggestions on this forum, I am replacing the 140 degree thermostat with a 160 degree thermostat (freshwater only for my boat- Lake Ontario).

I have some Permatex Aviation Form-A-Gasket (#3 I think), can I use this as a sealer for the paper thermostat gasket?

Thanks
Steve

 

[Lou C]

Yes, Permatex Aviation will work fine, you can use Merc Perfect seal (prob what they specified) or OMC gasket sealer (same thing).

 

[Bondo]

can I use this as a sealer for the paper thermostat gasket?

Ayuh,...... Ya need a marine gasket, with the brass crush-rivets in it, or the temp sender won't work right,....

 

[62cruiserinc]

Ayuh,...... Ya need a marine gasket, with the brass crush-rivets in it, or the temp sender won't work right,....

The gaskets I have are just paper, I got it from a marine store online. This is the first I have heard of a marine gasket for the T-stat. Is this something I can just ick up at West Marine? I assume the brass crush rivets are to carry electrical continuity to the T-stat cover? My temperature sender is not on the cover.

Steve

 

[62cruiserinc]

The picture below shows a variety of thermostat gaskets. The one that fits mine is in the middle, with the square notch at one side. The only gaskets that I have found with the brash crush rivets are completely round, as shown in the picture.

 

[harringtondav]

I use Permatex Aviation anywhere Merc. Perfect Seal is specified. 22 yrs w/no problems.

 

[62cruiserinc]

I see where the gasket with the crush rivets would go now that I have the thermostat housing apart. It goes between the intake manifold and the thermostat housing. The old gasket did not have crush rivets but it seemed to have a metallic polka-dot layer just like car exhaust manifold gaskets. This was probably for electrical continuity?

I can't find the crush-rivet gasket anywhere locally, so I may have to ground the temperature sending unit a different way.

Steve

 

[banderberg]

Ayuh,...... Ya need a marine gasket, with the brass crush-rivets in it, or the temp sender won't work right,....

@Bondo Can you explain what you mean? Does this apply to other engines? I have a 3.0L.