SenecaRex

I was having a discussion with a couple of friends, and apparently the opinion differs pretty widely depending on the application and make/model.

So I pose this question(s) to you all: When using Permatex Ultra Black as a gasket for cooling system (E.G. thermostat, etc), how long do you wait before filling it up and running/driving the car? A few minutes? Hours? Over night?

What about for gasket making in oil applications, such at the oil pan and what not?


Let's hear those answers!

JimBobNC

I seal my thermostats with the paper gasket or o-ring without using any sealer. If I ever had any trouble I would probably wipe both sides of the gasket with sealer then assemble and wait a couple of hours before filling the system.
Other uses, such as oil pans/differential covers, I lay the bead and let it skim over for a few minutes before placing and positioning the part with screws. I then loosely tighten the fasteners to initial squeeze out and wait overnight before final tightening and use.
The instructions say it fully cures in 24 hours.

SenecaRex

Sorry I meant Thermostat housing mated to water pump.
And yes, I agrees with you. However, I've heard people sometime just apply, mate the pieces, wait an hour, tighten, then just fill up and go.

Seems quite rushed and risky to me. Wonder if anyone else has done this and/or had horror stories.