Arkansas V6

Okay, I was at Walmart less than a mile from home and i noticed the temp gauge was laid down and temp light came on. pulled into a parking spot and smoked billowed from hood. First thing I thought was there goes the T-stat housing. Opened the hood couldnt determine source of leak. Limped home and the next day changed T-stat housing, thermostat, Upper and lower O-rings, and the sensor. flushed and re filled coolant.

The car drives fine but after running hard for 5-10 minutes the temp gauge lays down, light comes on but no coolant is leaking, no smoke and coolant levels are ok. The A/C (which has over the past month or so become less and less cool) is now awful and blows hot air when turned to coolest setting. I did a Re-charge to no avail....

Any help is appreciated

Update:
Drove car today. Drove fin. Punched it on the interstate and took my exit and the needle Laid down and I began to smell coolant. Pulled over and coolant was gushing out of the cap. So I'm assuming it was gushing out of the cap the first time at Walmart. What is the cause of this?

DayGlo

Could be a radiator cap... if it doesn't seal, the cooling system can't become pressurized. The coolant will then boil instead of staying liquid, causing all sorts of fun stuff. I'd replace the cap just in case - it's cheap, and as easy as it gets.

Arkansas V6

That was my next choice, probably should of started there rather than spending $185 at Ford for parts for Thermostat and stuff. Ill get a new cap and some fluid and give it another whirl. Changed the oil yesterday after the first time it overheated and oil looked fine so im pretty sure its not a head gasket. Flushed the coolant yesterday so i dont think theres any blockage and the car only has 50,000 miles and the stock coolant looked clean so i dont think blockage is an issue. If replacing the cap doesnt do it im really stuck...

thanks for the reply.

kevinmalec

I had a slow thermostat leak for over a year and never had any issues with the needle laying down or the car smoking. I had a buddy replace the thermostat housing, sensor, coolant and coolant cap with no issues.
Keep us posted!

Arkansas V6

So... Replaced the radiator cap and have had no issues since except for my brother driving my car through deep water. Realizing it was too deep and reversing and ripping my front spoiler off. Other than that jack@$$es mistake the car is all good

kevinmalec

Good to hear everything worked out with replacing the coolant cap! Inexpensive fix.

157dB

Not true.
I have the leaky thermostat housing problem.
The leak started about March of this year.
I partially unscrewed the radiator cap and taped
it in that position. I now do not run ANY pressure
and the leak has stopped. My MSD DashHawk
says 175-185F operating range with a 180F
thermostat installed. Water boils at 212F. A
temp I never see on the gauge. And I run her hard and
fast daily. The level has stayed the same and
the temperature is the same as normal even with
100F plus daytime temps.
I really do not think it was the Radiator Cap.
The root of the problem needs to be discovered.
Wait till it rears its ugly head again and diagnose
it or have it diagnosed properly.

ps the overflow coolant tank caps for the S197s are not cheap.

I guess Mr DayGlo was just guessing and not basing his
responses from actual experience with the S197 Mustang.