overheating and stumped

[cahillbilly30]

Hello!
I am completely stumped. I have an 02 Ford Explorer sport. It was running hot and I changed the thermostat, didn't help. I also flushed and cleaned radiator, didn't help. When driving the temp gauge stays at normal but when you get out you can hear the engine and exhaust ticking from being hot. The radiator cap is very hot as well as the top and bottom radiator hoses. There are no leaks anywhere, car runs fine and it has heat and ac. Been trying to get this fixed for a year. Even had a mechanic look at it and said it was fixed but it's not. Please any feedback or guidance is appreciated.

 

[MAS Tequila]

Is it overheating?

Are you losing coolant?

It may just be giving you the impression that it's hot.

MT

 

[cahillbilly30]

It isn't losing coolant at all. It seems hot because of the ticking in the exhaust and how hot the hoses feel. If I run the air for a long time and then you try to push the gas it hesitates like its going to die and then goes back to normal. If I take off the radiator cap and then start the vehicle and wait for it to warm up the coolant pushes out the hole but never starts to circulate.

 

[MAS Tequila]

That sounds like the water pump impeller has stopped turning.

Sometimes they come undone from the shaft.

Ether the t-stat isn't opening or the pump isn't pumping.

The exhaust will tick on any vehicle, that's just the metal expanding and contracting from the heat differentials.

MT

 

[cahillbilly30]

I am going to test the new thermostat to make sure it is working properly. Also, Can I check the impeller on the water pump or would I have to replace the whole thing? How can I test the pump? Thanks!!

 

[Bobmbx]

I am going to test the new thermostat to make sure it is working properly. Also, Can I check the impeller on the water pump or would I have to replace the whole thing? How can I test the pump? Thanks!!

Does your heater make hot air? If not, its your pump. If it does, and you're not losing fluid, and the gage is normal, and you've been driving like this for a while without seizing your engine.......there's no problem.

 

[cahillbilly30]

thanks for all the feedback.

 

[MAS Tequila]

I am going to test the new thermostat to make sure it is working properly. Also, Can I check the impeller on the water pump or would I have to replace the whole thing? How can I test the pump? Thanks!!

Take the t-stat out and see if the coolant in the radiator flows.

MT

 

[96whitesport]

If it pushes coolant out of the radiator immediately when cranked or started cold or hot, compression is leaking into the cooling system, usually means a head gasket.

 

[cahillbilly30]

If indeed its the head gasket how do I know or test for this?

 

[96whitesport]

To test for compression leaking into the cooling system you could use something like this
http://www.amazon.com/Lisle-75500-Combustion-Leak-Detector/dp/B0007ZDRUI

 

[cahillbilly30]

Ok so ran some tests. with radiator cap off, cranked engine no fluid came out. Let it run for approx. 3-4 min and then it started to push fluid out. No milky oil or antifreeze. It's very hot here today, 110 and I was driving about 65 and it cut out on me again. Started up a hill and it died. Still no fluid coming out or steam. Temp gauge shows normal. Sat for a bit and was able to make it up the hill. Could I be looking at the wrong thing could this be related to the fuel instead of the heat issue? I'm so confused. It only acts up when driving for longer than a half hour or more.

 

[2000StreetRod]

cooling - coolant & fuel

As I recall the 1997 and possibly the 1998 Explorer with the SOHC V6 had a dual core (two inch thick) radiator. But Ford decided to save some money and install a single core (one inch thick) radiator after that. One of the first upgrades I did when I purchased my 2000 Sport was to install a 1997 replacement radiator.

The fuel flowing thru the fuel pump helps cool the pump. Some members who drive in the desert have posted problems with fuel pressure. I suspect the pump is weak and overheats when the fuel gets too warm to adequately cool the pump. I suggest that you check your fuel pressure in the morning and again in the late afternoon after your Sport sat in the sun for several hours.

 

[cahillbilly30]

thanks for the info. I had a friend tell me the same thing about the radiator how they used cheaper one and the fins inside run side to side making it harder to circulate. I am going to have more tests ran tonight on the fuel and also the radiator. So frustrating because it usually runs great. I am in the process of putting it up for sale and want to make sure it's all fixed before doing so.

 

[cahillbilly30]

Ok. tests ran. Fuel is fine. You can tell it is overheating takes forever to cool off and the fluid smells cooked. This is what my conclusion is.
1. changed thermostat
2. flushed radiator
3. start engine with radiator cap off, no fluid comes out
4. with cap off running up to temp, you hear the thermostat open and the pump begins pumping fluid out the radiator. Radiator is not circulating
I think it's time to replace radiator. Is this what you think?

 

[fast_dave]

Hello!
I am completely stumped. I have an 02 Ford Explorer sport. It was running hot and I changed the thermostat, didn't help.

Before you changed the thermostat, and it was running "hot" - was your temperature gauge showing the temp was above normal?

I'm asking this because you write that your Ex's current condition (post thermostat) is that it's running hot, BUT your temperature gauge indicates the engine temp is "normal".

 

[cahillbilly30]

The temp gauge has always showed normal inside the vehicle and no fluid leaking anywhere. Motor gets so hot that it ticks and burns to the touch. Fluid smells burnt.

 

[fast_dave]

The temp gauge has always showed normal inside the vehicle and no fluid leaking anywhere. Motor gets so hot that it ticks and burns to the touch. Fluid smells burnt.

Just saying -

In order to establish a baseline to work from, you need to be able to accurately tell the engine temperature from within the vehicle.

Without that - you are just going to throw parts and labor at the problem and never really know what temperature you're operating at.

 

[Sish]

The temp gauge is unaccurate.

http://www.explorerforum.com/forums/attachment.php?attachmentid=41606&stc=1&d=1186338059 table of Temperature Sensor Values

On termostat installe 2 temperature sensors

With one wire-for gauge, with 2 wire-for PCM

Measure the voltage on both them and сompare with a table.

If the values match with the table-sensors in good condition.

Sorry for my poor english.

P.S. thermostat check: Fill the pot with water, t-stat place in water and bring to a boil. When the water boils t-stat should be fully open
P.P.S. and check your radiator fan clutch:
To check the fan clutch, first with a cool motor (motor is STOPPED!), the fan should spin relatively freely, some resistance, but should spin, when the motor and radiator are hot, turn the vehicle off and the fan should be harder to turn than when it was cold. If your fan does not turn by hand when cold, and if it turns by hand when hot, there is a problem with the clutch

 

[cahillbilly30]

Thanks for the info! I will test these tomorrow.