Thermostat Test Results.. Bad?

[HadesOmega]

I took my thermostat housing out to replace the Oring gasket on the water pipe cause it was leaking. Since I had it off already I went ahead and took the thermostat off.

I put it in a pot of boiling water and checked the temps. Here are the results:
Starts to open: 200F
Full Open: 210F
Closed (cooling): 190F

So from what I gather I think this thermostat is rated for 200F or its opening too slowly. I thought the rating means the thermostat will start to open at the rated temp and be fully open about 10 degrees later. I was hoping for a 180F open.

Think I should get a new thermostat or does that sound normal? I did the test repeatedly and go the same results and even changed the pots once. The thermo could be off but I doubt it.

 

[kenamond]

They cost $8 at AutoZone. Cheap peace of mind.

 

[DSMcrazy3]

210 is fine for full open, but like Kenamond said, they're cheap. If a new one will give you piece of mind, go for it.

 

[Defiant]

The spec isn't stamped on it?

But yeah, just replace it if it's out. The war's over, we can get brass again. Stay with the stock specification.

As far as the water's concerned, a round seat is "fully open" when it's ¼ its diameter off its seat. That's why a thermostat that's stuck open a sixteenth will keep an engine from ever reaching operating temperature if it's cold out.

 

[HadesOmega]

sounds good I got a 180 Beck Arnley one for 21 bux. Is it really 8 bux at autozone? I will check it next time I go.

And no the the old thermostat did not have a temp rating on it. I'm assuming it was a 190... Think it was a Stant it doesn't have a jiggle valve it had that little tiny hole on the very outside of the plate, the beck arnley one has the jiggle valve.

 

[Defiant]

Well, a hole can't come loose and wander into the cooling system.