Overheating Symptoms

[Ursley]

I have done all the easy work to try and fix my overheating problem. I changed the thermostat, changed the radiator cap and the car is still overheating. Here is what it is doing.
1.) Car will overheat, then for some reason start to cool itself quick. Then starts to overheat again.
2.) When the car is overheating, the heat does not work, but when it starts to cool itself, heat blows like fire.
3.) Top radiator hose looks as if it is under a vacuum when I pop the hood after it gets hot.
4.) When I look in the radiator when it is cold, radiator coolant level is low
5.) Coolant is leaking from somewhere, may be the weep hole on the water pump, but I cant tell.
6.) Radiator is still cool after car heats up.
7.) Hissing sound like the system is under alot of pressure, if I take the top radiator hose off the water neck, hissing goes away.

These symptoms tell me that there is no coolant flow through the system, my first thought would be a bad thermostat, but that is not the case, it is brand new. I also thought there was a bad air pocket in the system, but am not sure on the validity of that. Do I have a bad water pump, what symptoms occur when the water pump is bad as far as cooling performance, I know the weep hole thing.

Any help would be much appreciated.

Thanks


__________________
Mods Include:

TFS Aluminum Heads, GT-40 Intake, 3:73 Gears, King Cobra Clutch, Mac Cold-Air Intake, Aeromotive AFPR, 65mm TB, 70mm Pro-M MAF, Mac Headers, Bassani O/R X-Pipe, 2-chamber Flows, 1.6 Roller Rockers, 190 lph Fuel Pump

 

[cmclean]

Make sure your electric fan is working all the time?

 

[Ursley]

What is an easy way to check if fan is working?

 

[HazMat404]

let it idle for a few minutes and warm up....you just look or feel with your hand (carefully) that its movin

 

[Ursley]

I figured it out, I had a bad air pocket in it, I burped it, but now I have a new problem, the damn fan motor is seized up. But I think I have Ford convinced that it is covered under the recall. So well see.

Thanks for the help

 

[HerrcomesTroubl]

next time you have to do somthing like thermostat or somthing where you drain some coolant off. Jack the front of the car up before you begin to fill the tank back up. Also while pouring coolant in... make sure and "pump" the top radiator hose to make sure all the air is out... Another thing. just get a cheap light from autozone or somthing and wire it inside your drivers compartment that way you KNOW the fan is on. I had 2 diff problems
(1) The ECT went out on me on a road trip, car got up to 240.. warped new set of alum heads.
(2) the Plug that goes to the fan burnt out on the ground side.. (wear and tear) fan didnt come on once again.. car got 2 well over 220.... only headgasket that time. So i hard wired my fan to a switch in the dash.. along with a light.. and its also got a thermostat on it so it comes on at 180* if the light doesnt light up ( which is hansn't NOT.. lit up yet "so far".. i just flip the hard wire switch and make sure it will come on.

Hope some of this mumbo jumbo helps...


-Cody

 

[94GTLaserRC]

WHEN...You get a $25 code scanner from Walmart, and put it on, it checks the low and high speed fans at system check.

Clean the top of the water pump, then check for new coolant.
Originally, it almost sounded like the TSTAT was not opening, by the symptoms.
RC

 

[HRT11]

headgaskets....sorry

 

[hawaiian]

I know your better than this.

I didnt see any reason why u might have done this but when your T-stat is backwards it does the build heat then cool quickly. the heater not putting out heat is a good sign u have low coolant. the hissing is from over pressure is a good sign of a bad radiator cap or the very evil blown gasket ( ) . the coolant should be coming out of the top of the overflow where the little hole is by the cap. and im gonna stop here cause even im getting lost. hope this helps reinforce your ideas. i know how round and round the cooling system gets hope its a cheap fix brutha.

when it starts to cool quickly the coolant is rushing back into the sytem form the overflow more likely there could be a clog in the system. i had a promlem with my cooling system that was pretty close i am lucky to have a EPa pit at my jobsite and i drove my car there and pulled the hoses i hooked water up to the block and you wouldnt believe how much crap was in there. i also flowed top to bottom and bottom to top on the radiator. this seemed to fix the cooloing problem alot. i wont say for sure because my problem isnt constant and happenens randomly. also my car isnt on the road AODE freaked out but ill be posting some Qs' bout that elsewhere.