ive just done an engine rebuild and im putting the radiator hoses on i come across the thermostat that was in it. is it ok to start up the engine with that one even though it has a little gasket sealeron it or do i really want to get a new one. and if i need a new one what do i specify? size, heat, engine size?

 

if you just went through all that 'restoration' don't skimp out on the cheap stuff Get a new 180F thermostat. Cheap insurance.

...and yes, they can go bad (get stuck open or closed)

 

Absolutely dead on the money. Get a new one.......You can test the old one if you want, but putting it in a pot of boiling water to see if it opens, but it ain't worth the little amount of money to keep the old one. Just get a new one. Brand doesn't matter, and the 180 degree is the best for these old engines with a good operating cooling system.

 

They are under $10 with gasket at your local parts store, just make sure to get some gasket sealer when putting it in. it will give you a better seal and make the install process even easier than it already is. Definate preventive maintenance!

 

all you have to do to test it is to put some water in an old coffe can and heat it up, when it gets good and hot stick the thermostat in it, if its good, then you should be able to see it open, and when you pullit out and it cools down it will close.

but thats only if your really cheap, i'd just buy a new one

 

i heard that during the summer you have to take out the thermostat because it will get stuck do to the summer heat is that true?

 

Hi ya'll.
Do they make a 160 degree thermostat? I just put in new guages and it hasn't gotten above 160 degrees? I was thinking about changing it out with the 180 degree thermastat. Is that the better one for these old mustangs?
Thanks,
John

 

Taking out the thermostat during the summer won't hurt anything, but it is an old wive's tale about it getting stuck. It works the same during the summer as it does during the winter. And yes, they do make 160 degree thermostats, and yes the 180 degree is the best one for these old engines. If you drive your car for more than a few blocks, I can guarantee it is getting above 160 degrees. The job of the thermostat is to NOT open until the temp of the thermostat is reached. It doesn't keep your engine any cooler, so the 160 will open at 160. And the 180 will open at 180. These engines operate best at about 190 degrees.

 

If you remove the thermostat you may cause the car to overheat as the radiator is not allowed to cool the fluid its moving so fast.The best way to test one is to use a candy thermometer(very accurate) in the water.Put in the stat and raise the water temp until you see it open and check the temp.If you just throw it in boiling water it is already to hot.I have found older Ford stats that flow better when open,and have a bleed hole predrilled.These work very well.