Right Stuff Gasket maker

[C.Costine]

I noticed in high humidity the silicone is harder to get stuck on the metal to seal

I have noticed that rust will creep under RTV silicone much faster than others such as the Permatex. The silicone can stick well to one surface and poorly to the other so the objective is defeated.

[Daryl Smith]

I have been using 'The Right Stuff' for several years now. This stuff works.
Two problem areas that seem to come up regularly for me are the oil pan and thermostat housing. make sure both surfaces are clean and dry, only apply as much as needed for minimal 'squish' - almost nothing comes out the sides - let cure for 24 hours, and no more leaks (no gaskets).
It does not harden solid, but, it is a pain to remove, both separating the parts and getting the stuff off the parts afterward - tricky on aluminum parts you want a flat surface afterward. No problem for the majority, but, if you are anticipating taking the part off again soon (racers, testing....) you may want to use something easier to remove. ymmv.

[nismou20]

I’ve only used it once on someone else’s water pump and worked great. Seems to me if it bonds good and hard to pull apart later, it must be doing its job. Oh I did use it on a tach cable crimp that was leaking oil and it sealed well. It is like hard rubber once dry. Really tough.

[SLOroadster]

I just tried using the Toyotabond sealant on my water pump backing plate. The pump leaks from exactly the same place it did before, only worse. It had a month to dry, I'm not impressed. All the gasket surfaces were flat, clean and dry when I assembled it. I filled the cooling system, started the car and not a minute later there was a weep of coolant along the top of the water pump, right on the joint between the back plate and the main body of the pump.

Will

Sounds like there may be some unidentified problem still...

It was a strange issue. Drained everything out, the sealant never actually cured. It was all gooey. I cleaned it off, cleaned everything with acetone a second time, tried again. Seems to have sealed fine, after 30 min at most. Now trying to figure out why there is a leak along the side of the oil pan, with no obvious leaks topside.

Will