Stuck Open T-stat?

[RS12Turbo]

Before I pull the t-stat out......what are the signs that one is stuck open? I was driving today, and the temp gauge was where it normally is....which is almost in the middle. I got on the gas to get out in traffic, and shortly after, I noticed the needle on the temp gauge started lowering.....until it stayed just right above the "C". When I got home, and after the engine cooled completely.....I pulled off the rad. cap, then cranked up the car. I noticed that the coolant level right away came up to the top of the rad, and started overflowing. Usually the coolant won't raise until after about 5 mins after a cold crank.I'm hoping that it's just the t-stat is stuck open......anything else it could be?

[float_6969]

You nailed it. The T-stat is stuck open. I think they must have a way to fail safe or something because I've had a T-stat fail in one other Nissan and it stuck open as well. My old Pontiac 3.1L V6 and my ford 2.4L both had stuck T-stats and they both stuck shut.

[RS12Turbo]

Yeah...........it's one of the fail safe type. I guess I'll pluck it out and replace with another one.Part of the problem might be I used the t-stat from my ca18et, since it only had about 8k miles on it, and I paid like $18 for it.....but it is slightly smaller in diameter than the old ca18det one that came in the motor.Ehhh, thats what I get for trying to save a few bucks

[r34 gtr]

trying to save a few bucks? son my new thermostat was a scant $9 from autozone, and we're in the same area so the prices have to be the same. ca18de ftw. they have 3 or 4 temps to choose from too!

[RS12Turbo]

Oh, I know......it wouldn't of broke the bank or anything.........I was just trying to get more life out of the one I had since it barley had any miles on it to begin with. Yeah, I'll go with a Stant one........because spending $18 on the Mr. Gasket one didn't pay off.......haha!I hadn't seen this style t-stat before, so I said what the heck....why not?

[RS12Turbo]

Yep.......that was it......stuck wide open! New one reads just shy of the middle of the gauge........

Thanks everyone