Guys, you have all been great in answering my questions (and I am FULL of questions), so I am zinging a few more your way--

the other night I checked the antifreeze in my Plymouth P12 and added about 1-1/2 pints of premixed prestone. Then took her out for a spin (about 60 miles). It was a hot evening (90-95 degrees) and I pushed her right along at about 55 mph. She didn't overheat, but the needle on the temp gage did tickle the "red" zone. Normally when I drive her the needle stays between just right of center to about halfway between center and "red". Is this normal for these cars under this set of conditions? My experience with thermostats (admittedly from 30 years ago) is that they give out right away, not gradually, so I don't think the problem is there. Also, I am thinking of draining the block and replacing the anti-freeze. You used to be able to buy back-flush kits to clean scale and what-not from the cooling system. Are these still available and is it advisable to use one on this car? Thanks.

Bruce

 

Thermostat's can get sticky over time and can overheat sometimes and other times they will be fine.. I would replace it just to be on the safe side esp. if it been in there for a long time.. I would use a 180* stat and see what happens... Bill

 

Thanks, Bill--I ordered one this evening from JC Whitney--it's a Stant, and is supposed to fit the 201 cu in L-head. I know that thermostats used to be unreliable, and that you could get a bad one right out of the box. I remember putting them in pot of water on the stove and seeing if they opened alright

 

Have you had the radiator flow checked ?

 

And Also Back in with Distilled water and Coolant.....

 

WOW, a lot here. How do I get the radiator flow checked? A regular garage can do this, I suppose? Can I check it myself?

Bruce

 

Radiator shop

 

Car has been running at normal temp the last few days, except today I took it out and let it idle about 10 minutes. She got hot again, but once I started driving her, she returned to normal. I turned the heater on for a bit and this may or may not have helped.

Bruce

 

Did you do the stat yet?

 

That's an old trick. I remember my dad turning the heat on if the car got hot towing the boat through the desert. Wouldn't stop Just slowed down & in a few minutes the temp would go down

 

Haven't done the stat yet. That will have to wait until into the week.

 

Oh OK hat will probably fix the problem. Keep us posted...Bill

 

Still waiting on stat. Jeez, JC Whitney can be slow!