Thermostat for 65 Mustang

[old1]

As per my signature I have a 65 mustang with the 200 cubic inch 6 cylinder with automatic trans. Lately I have noticed the temp gauge going a little higher than Normal, then dropping back to normal. Today I glanced down at the gauge after a few miles at 65 mph on the highway while stoped at a red light, and the gauge read virtually all the way to hot. It almost immediately started to come back down while sitting there idling. Previously it would climb some when idling after a highway run, but not nearly this much. I am thinking that the thermostat temporally stuck. So since it has been several years but only a few thousand miles, maybe I should invest in a new thermostat. My question is, other than going to ford dealer, is there any decent brand to use?? Years ago I used to use whatever brand my local independent auto parts store sold. They were usually major brands.

 

[bullwinkle]

Stant Superstats have been pretty good for me, and I've also had good luck with Motorcraft ones in Fords (albeit newer ones).

 

[DuckRyder]

Motorcraft.

You don't have to go to the dealer to get one.

 

[Lubener]

Go to Rock auto and get a Motorcraft. Stick with a 180 degree. Stant used to be ok too but quality doesn't seem to be where it once was. It's a flow problem, if the stat doesn't help, may be time for a radiator.

https://www.rockauto.com/en/moreinfo.php?pk=383933&cc=1333370&jsn=462

 

[maxdustington]

Originally Posted by Lubener
It's a flow problem, if the stat doesn't help, may be time for a radiator.
That's what I'm thinking. I've heard of lazy tstats before and owned a car that had a stuck open tstat but It really sounds like OP is approaching the limits of cooling capacity. Time to yank that stat and boil it.

 

[Wrenchturner44]

You might also want to check the temperature sender probe. It might need replacing too. Can probably be checked using an ohm meter.

 

[JeffKeryk]

Great car. Good luck with the t-stat.
Personally, I would inspect all the cooling components and replace as necessary.
Then drive that 'Stang another 50 years.

 

[Chris142]

The stant and motorad ones seem ok. Stay away from the failsafe ones. Those are junk.

 

[Trav]

As others have posted I also suspect the radiator is partially clogged. Of course do the thermostat first and check the sender but be prepared to do the radiator.

 

[Chris142]

That mustang does not have a shroud on the radiator does it? You can easily feel the core for cold spots( after you turn it off).

 

[Linctex]

Originally Posted by Lubener
It's a flow problem, if the stat doesn't help, may be time for a radiator.


My first thought as well from your description.

You can try a white vinegar or citric acid flush through the system - it should help the radiator efficiency a lot.

 

[old1]

OK, thanks all. I will try a new 'stat tomorrow, and maybe flush the radiator a little while it is apart. And see what happens next time I drive it.