Overheating Problem (Need Help)

[Arch Angel]

Car: 2001 Cobra

Problem: Car overheated going to work. AC stop blowing cool air & then I saw that the temp guage was right by the red tick mark, antifreeze was silling out around the cap. I took the car to a general mechanic shop. They replaced the thermostat, refilled my anti-freeze & I drove off. Not two miles down the road, same thing happened. Turns out there was a hole in the radiator. Replaced the radiator. Refilled the antifreeze.

Thermostat: NEW
Radiator: NEW
Checked the water pump: OK
Checked the Fan: OK

Drove it 50+ miles home (No Problem)
Drove 30+ miles to work & lunch (No Problem)
Drove 15 miles home: AC cuts out again, looked at the temp guage & it is rising. Heading towards the red tick mark again.

Shut the AC Off, turn the heat on to full blast. The temp guage started to drop, back to normal. Seems like the thermostat is sticking & not allowing water to flow until it gets to the point where it is almost over heating. No anti-freeze is spilling / leaking out.

I can drive for 2-3 miles before I have to turn the AC off, turn the heat to full blast.

Any ideas what it could be? Is there a way in 01 Cobra's for the thermostat to be installed upside down? A bad new thermostat?

Keep in mind:

Thermostat: NEW
Radiator: NEW
Checked the water pump: OK
Checked the Fan: OK

[wrenchturner]

These motors can be a biotch to get all the air out of the system, did they open up the bleeders and get all the air out of it.. might have a big air bubble in there maybe... its just a idea to go on.. to eliminate if nothing else.

Car: 2001 Cobra

Problem: Car overheated going to work. AC stop blowing cool air & then I saw that the temp guage was right by the red tick mark, antifreeze was silling out around the cap. I took the car to a general mechanic shop. They replaced the thermostat, refilled my anti-freeze & I drove off. Not two miles down the road, same thing happened. Turns out there was a hole in the radiator. Replaced the radiator. Refilled the antifreeze.

Thermostat: NEW
Radiator: NEW
Checked the water pump: OK
Checked the Fan: OK

Drove it 50+ miles home (No Problem)
Drove 30+ miles to work & lunch (No Problem)
Drove 15 miles home: AC cuts out again, looked at the temp guage & it is rising. Heading towards the red tick mark again.

Shut the AC Off, turn the heat on to full blast. The temp guage started to drop, back to normal. Seems like the thermostat is sticking & not allowing water to flow until it gets to the point where it is almost over heating. No anti-freeze is spilling / leaking out.

I can drive for 2-3 miles before I have to turn the AC off, turn the heat to full blast.

Any ideas what it could be? Is there a way in 01 Cobra's for the thermostat to be installed upside down? A bad new thermostat?

Keep in mind:

Thermostat: NEW
Radiator: NEW
Checked the water pump: OK
Checked the Fan: OK

[dewone]

Check the water pump.

[Levi]

and the high speed on the cooling fan may be out. You need this when the ac is on.

[Rick@Amazon]

I think the guys are right. If all components are ok I bet it's a air pocket. Bring the car up to temp then carfully crack the bleeder on the crossover. You may have to do this a few times to get the air out. If all air is out I'd do a leakdown test to made sure there is no headgasket or other problems.


Rick

[2many]

My 03 did the same thing a couple of weeks ago. Turned out to be air in the system so the thermostat wouldn't open.

[ausie]

Air pockets are a big issue. If you have air in the block, the water pump will not displace it. Just adding coolant to the resivior (expansion tank) will not help unless you add coolant to the bleeder. Probably the reason the AC turns off is that the temps are placing the engine in limp mode. To get the air out can be a tedious task, fill up at the bleeder bung, close it, turn the heat on full, start engine till it warms up, shut off, let cool and repeat the fill process at the bleeder bung. If you fill up with the cap off of the resivior, the coolant will overflow, keep the resivior cap on the first few times and only add to the bleeder plug. Air pockets in the block will cause a low pressure and the coolant will begin to boil hence the spewing of coolant out of the resivior.

[ProfChaos]

When a Ford dealership in FL replaced the radiator on my '96 Cobra, I had the same sort of trouble. It actually took them a day-and-a-half to dissipate the large air bubble that formed when the radiator was replaced.

On the second day of their trying to get rid of the air bubble, the Service Manager told me that the service tech needed to drive the Cobra around a little more in order to get rid of the last of the air bubble. I was livid, telling the Service Manager that I know that running the 4.6 modular Cobra engine even a little hot is a bad thing to do and that there had to be a better way of getting rid of the bubble, a better way than stopping when the engine began to overheat. (I lost two Probe GT's to that foul demon Overheating and wasn't about to see the same thing happen to Lorena the Cobra.) :mad: :mad:

The Service Manager then had the service tech use a vaccum pump at one end of the system to bleed-out the air bubble--the process he should have used at installation. Once they used the vaccum pump to clear the system, things were fine right away...no problems during the service tech's follow-up "joy rides." ;)

cheers,
Professor Chaos