Sounds like your sensor that turns on your fan is bad.   Run 12 volts  from another source and see if the fan turns on or not.  If it turns on its your sensor.  If not it your fan.   The Hose blowing off was probably the pressure building up from your engine overheating.   I had the the upper hose blow off going 60 mph.  I had so much smoke flying out of the hood I thought I was in a Nascar Race.   Maybe your hose wasn't completelly tight either.   Thats what happen with mine.

Steve69

No problem. Got a fan sensor in one hole of intake that turns on at 210 and off at 180. I think, it's been a while. Had the same sensor on the previous engine and it worked great. Temp gauge is hook to a second sensor in the hole right before the thermostats housing in the intake. I have plans replacing the gauge. Guess I will also be replacing the sensors. I will also test the fan tomorrow. Thanks for the info guys. 

do you have a relay in the system? if so, you might check it if its been sitting that long. if not, you need one to keep from burning up the switch. fans pull alot of juice when they kick on & its really hard on the switch if there isnt a relay in the system.

I think you'd be better off with a13psi cap. In an overheating situation a 22psi cap will put more load on other cooling system components, like radiator and heater hoses, with no real benefit and possible negative results like you experienced. Glad you weren't driving and didn't take a hot shower and glad it didn't pop a heater core hose and dump all that inside the car or worse, on a passenger.

Last edited by McStang (5/29/2013 12:41 AM)

T, pull the wires off the sensor the operates the fan. If there are 2, jumper them together, if it is a single wire jumper to gnd. See if the fan relay picks up. (Keep in mind key may need to be on, don't know your system) If the relay doesn't picks up, try to measure voltage across the coil of relay. If 12 volt is presant relay probably bad. If relay picks up but fan doesn't come on try to measure voltage at fan. If voltage presant fan may be bad. If all things works when jumpering the sensor then the sensor is probably bad. Keep in mind when jumpering out equipment for testing it is a good idea to use a jumper made with a in line fuse. In case you short something out the fuse will blow, less likely chance to cause damage.

My very simplistic method of tracing fan problems. 
OPEN HOOD
SEE IF BELT IS STILL ON
IF BELT STILL ON, FAN OK
IF BELT OFF, REPLACE BELT.

Tmac wrote:

So had the mustang at the muffler shop. Drove it home and noticed that my electric fan did not turn on. So I had it idling on the driveway and exame d the engine compartment. No fan and my temp sensor is stuck at 160 when the engine is on or off. So I put it up in the garage. I was gonna let it cool off and put the new plates on the car. Just got the rear plate on when I heard an explosion. I looked up just to see antifreeze spewing all over the ceiling and over everything in the garage. Upon inspection, the upper radiator hose had come off the thermo housing. 

1- how can I check the electric fan to see if it is bad. It's been sitting for 4 years. 
2-new thermostat and I tested it before install. 180 degrees. 
3-new water pump. 

Any suggestions??? I'm at a lost. I did flush everything and water flower great thru the raditor. After filling the rad, I ran the car with the rad cap off to see if it had flow and it did. God was watching out for me cause I almost started with the front license plate!!!!

 
Tmac, one thing I have not seen asked or answered is where the power for the fan control relay is coming from: switched or unswitched.  The fan suppliers provide instructions stating that the main power for the fans must come directly from the battery (through fuse and relay), but they often leave the choice of how to power the fan controls to the user.  If the power to the fan relay is switched, then the fan will stop when the key is turned off.  The engine continues to generate heat until the key is turned off and the block and heats have a lot of heat in them.  When the water pump stops pumping the coolant in the block and heads continues to remove heat, known as heat soak. Since the new working thermostat you installed does work, the hot water had a clear path to the radiator.  As the heat soak is removed from the engine to the coolant the coolant pressure will continue to go up.  The radiator cap is designed to be the weak link in the coolant system, venting to releave the excess pressure.  Its possible your only problem is that you did not get the hose clamp tight enough when you changed the thermostat.

Figure out how your fan control is powered, then you will have a better understanding of how the system is supposed to work.  If the fan control power is unswitched, the fan should have kept running to remove heat from the engine.  (yes I know the water pump was not running, but the water will thermosyphon through the engine as long as there is a significant temperature difference between the coolant in the radiator and the engine). Most late model vehicles have unswitched fan controls or time delay fan shutoff to all fan run-on after engine shutdown. The more complex (more expensive) aftermarket fan controllers have fan run-on circuitry to run the fans until a cooler temperature is achieved or until a set time after shutdown.

McStang wrote:

I think you'd be better off with a13psi cap. In an overheating situation a 22psi cap will put more load on other cooling system components, like radiator and heater hoses, with no real benefit and possible negative results like you experienced. Glad you weren't driving and didn't take a hot shower and glad it didn't pop a heater core hose and dump all that inside the car or worse, on a passenger.

 
McStang,  with you being in Norcal you probably don't have a good feel for what we are dealing with here in Texas for heat and trying to keep these old Mustangs from blowing their tops in the hot months.  That 9 psig difference between the 22psig radiator cap supplied by the radiator manufacturer and the 13 psig cap you suggested will give about another 10 degrees F before the coolant starts boiling.  Us Texas boys (and girls) need all the help we can get.  Although it wasn't that hot last summer.  The highest temperature I measured on my back porch last year was only 115 F. Forty miles west of here it was approaching 120, not counting the range fires.

Tmac,
As you probably know, the radiator cap's job is to pressurize the radiator to keep the coolant from boiling at 212 deg.  With a 22# cap, that raises your boiling temperature to 278 deg. before the cap relieves the pressure.  That's alot of pressure in a coolant system.  For every 1 pound of pressure on the cap, it raises the boiling point 3 deg.'s, so that would be 66 deg. above the normal boiling point of 212 deg.  Hope this helps.

McStang wrote:

Hornman wrote:

The highest temperature I measured on my back porch last year was only 115 F. Forty miles west of here it was approaching 120, not counting the range fires.

That's HOT! Where I'm at I did the opposite of what Tmac did - I deleted the AC instead of deleting the heater. I've always got the windows open when I'm in the car, in the daily driver too, just like it that way and it's only ever been hot enough around here for AC maybe a couple of times a year. Stay cool!

Dont drive to Bakersfield in the middle of the summer!