overheating only while parked

[5.0 coup]

hey anyone know why coup 5.0 overheats when i am parked, but as soon as i get on the road it cools down and stays cool. 160 thermastat, 3 core radiator, knew water pump, good cerculation in water, checked oil to see if any sighns of water leak in head gasket nope. any info would be greatly appreciated thanks Leo

 

[5spd GT]

Do you have an electric fan? Some of the aftermarket ones (especially if not wired up correctly) don't flow enough air (push or pull) to keep it cool at idle. I have the same problem.

I'm guessing you do have enough coolant and have an overflow tank right?

I would suggest getting a 180* thermostat instead of the 160* thermostat.

Good Luck

 

[MrKwik]

The 2 things that come to my mind are fan shroud and clutch. Havn't removed the shroud have ya? Make sure the fan clutch is good. It could be bad and the fan isnt spinning fast enough.

 

[HISSIN50]

Leo, as both David and MR K. jumped all over, it is likely a fan situation. and like David said, if electric, make sure it flows enough and simply comes on! some fan controllers are finicky and some just suck. what temp do you have it set to come on and off at?

are you using the stock gauge to make the determination of overheating? are you boiling over? that is what overheating means to me (as opposed to running hotter than desired).

if you have the stock fan set up, provide info on the age of the components and any testing you have done (fan resistance hot vs cold, etc).

basically, please provide more information.

good luck.

 

[sgarlic]

http://forums.stangnet.com/showthread.php?t=539614 .. that your first thread asking for help about it? I see you have a regular mechanical fan and 3 core rad.. do you have the shroud on? Are you running underdrive pullies?

I had a jeep cherokee that did the same thing.. it would run fine, but the first long stop light I came to, it would go to almost 260.. it never would go back down much even if I got up on the highway once it got that high.. I never did figure the problem out.

Have you tried replacing your radiator cap? If its not holding the right pressure it could cause hotter temperatures.

 

[5.0 coup]

overnheating

yes i have a shraud and a knew cap replaced the fan and clutch. but i will replace my 160 to a 180 and see if that will help thanks leo

 

[5.0 coup]

and i would of thaught that a 160 would keep the temp cooler. yes i do have under drive pullys.

 

[HISSIN50]

what about the gauge or other indications that you are overheating?

 

[sgarlic]

Checked all hoses for kinks/cuts/abrasions? (Including heater hoses and those gay ones going to the throttle body?)

 

[tomabram]

A thermostat will have zero effect on weather you overheat while stopped. 160, 180, dont matter. Its the fan that keeps the motor cool . Make sure the fan is kicking on.

 

[dcarlson]

Definitely an airflow problem. 3 core radiators actually sometimes make it worse, because they are harder to pull air through. You can put the stock water pump pulley on to speed the fan up some. You will still have most of the power gains from the pulleys because the underdrive crank will still underdrive everything.

 

[Stroked91]

Ditch the 160º thermostat. Mine did the same thing and after changing to a 180º everything went back to normal. It's an open / closed loop problem (same as not running a thermostat) because the motor never gets up to temp. and stays in open loop.
I also had fan clutch problems about a month later. Replaced the fan clutch and everything was good again.

 

[5.0 coup]

thanks for all the info i still will put a 180 for a few bucks and see what happens, yes it would boil over and i would check the temp with a heat gun right at the neck of the thermostat and it would go up to 280 as for the pullys the water pump pully is stock. ? how do you know when a clutch fan is going out their is resistance on it and no signs of leaks.

 

[Stroked91]

My stock one leaked and the heavy duty didn't but it did get pretty hot sitting in traffic and didn't start to cool down until I got on the freeway. A pretty good indication of a fan or fan clutch problem. I just replaced the HD today with an electric dual and no more heat problems after a 1/2 an hour idling in the garage.

 

[HISSIN50]

how do you know when a clutch fan is going out their is resistance on it and no signs of leaks.

thermostat clutch fans have a viscous coupling with a bi-metallic spring. as the clutch warms up, the spring moves to expose an orifice to allow the silicone to move and lock up the clutch.

the spin test is subjective - enough so that I dont often post about testing it. basically, the fan should spin a good bit easier when cold than warm. but it it subjective. they can fail locked up (always tough to spin), but that does NOT sound like a possibility for you (quite the opposite).

my personal opinion is that the stat is not going to make much difference, since you do run cool at speed. running a 160* stat is NOT like running no t-stat. when running no stat, the lack of an impediment is a major issue (why people run restrictor plates). if you actually ran at 160*, you could have engine management issues (you would be in closed loop, but not in complete warm-strategy). since we have HEGO's, we go into closed loop within a couple minutes of start up, even though the trim is allowing for cold and warm up strategies via the ECT keeping it apraised of the engine temps.

good luck.