Overheating Explorer

[bronco2blue]

94 explorer, overheats at idle, cools down while moving.

I've been dealing with overheating ever since I did some exhaust and transmission work to my 94 explorer. To get the trans out I had to remove the exhaust up to the manifolds. I ended up cutting the y pipe out and ordered a new replacement from walker. I installed it but it doesn't fit properly. The bottom of the pipe touches the transmission. Does this create enough heat to overheat the motor?

The other problem is a short in the SPOUT circuit. All I know about spout is that it controls timing. My truck wouldn't start with the short so I took it to a mechanic who grounded out the spout circuit. Could this be the reason I'm overheating? I assume the engine isn't getting the right air/fuel ratio without the SPOUT.

Or could it be something more simple like a fan clutch, water pump, or radiator?

 

[Andy D]

over heating at idle but OK at speed, is a classic symptom of a bad fan clutch

 

[bronco2blue]

How can I test the fan clutch before taking it apart?

 

[Big Jim M]

Wow!

94 explorer, overheats at idle, cools down while moving.

I've been dealing with overheating ever since I did some exhaust and transmission work to my 94 explorer. To get the trans out I had to remove the exhaust up to the manifolds. I ended up cutting the y pipe out and ordered a new replacement from walker. I installed it but it doesn't fit properly. The bottom of the pipe touches the transmission. Does this create enough heat to overheat the motor?

The other problem is a short in the SPOUT circuit. All I know about spout is that it controls timing. My truck wouldn't start with the short so I took it to a mechanic who grounded out the spout circuit. Could this be the reason I'm overheating? I assume the engine isn't getting the right air/fuel ratio without the SPOUT.

Or could it be something more simple like a fan clutch, water pump, or radiator?

Nope! NO EXHAUST PIPE should EVER touch any part of the transmission!
This will put too much heat into the transmission.

By all and any means move the pipe.

Then we have the spout. Was this mechanic at a shop? Or was this mechanic a guy that lives down the street? If the second then quickly take the Ford to a real shop so it can be checked on. If the spout isn't working properly it can cause overheating.

Then we get to the overheating, does the coolant come out of the overflow? Or does the gauge simply move up a little? Up a little is normal in most vehicles in the summer time.

Big Jim

 

[RonD]

Start up cold engine, let it run for 30sec-1min, turn it off
Open hood and try to spin fan, should spin easily
(have to start engine and run it briefly, so fan clutch valve will open)

Go for a drive so radiator warms up, radiator heat is what activates fan clutch, it has a bi-metal spring on the front that is warmed up by radiator heat, this activates the valve that causes fan to spin closer to engine/waterpump RPMs.

Stop engine open hood, spin fan, it should not spin, should be very hard to move at all.


Yes, classic symptom of failed fan clutch is rising temp when stopped and lowering temp when moving again, it has to do with air flow thru radiator.
When stopped fan should suck enough air thru the rad to keep it cooling the coolant down, fan shroud is an important part of this system as well.

 

[bronco2blue]

I know the exhaust pipe touching the trans is very bad. I am looking for another explorer to get a factory y-pipe from. The SPOUT was bypassed by a reputable auto shop. They said to trace the short and take apart the dash it would cost over a grand, so I just let them temporality make my truck drivable. When it overheats the overflow reservoir boils and spills out.

RonD, I ran the truck for a minute and the fan spun easily. After driving around and getting the engine at normal operating temp the fan still was easy to turn with my hand. I tried to spin it and it only did about 1/8 of a revolution, but it was still easy to rotate.

 

[RonD]

Replace fan clutch

If you have another vehicle with fan clutch or a friend with one, test theirs when rad is warmed up, should be tight not easy

 

[Big Jim M]

temporary?

I know the exhaust pipe touching the trans is very bad. I am looking for another explorer to get a factory y-pipe from. The SPOUT was bypassed by a reputable auto shop. They said to trace the short and take apart the dash it would cost over a grand, so I just let them temporality make my truck drivable. When it overheats the overflow reservoir boils and spills out.

RonD, I ran the truck for a minute and the fan spun easily. After driving around and getting the engine at normal operating temp the fan still was easy to turn with my hand. I tried to spin it and it only did about 1/8 of a revolution, but it was still easy to rotate.

That word bothers me. By temporary do you mean you do not have advance in the timing?
Did the engine overheat before the spout problem?
If it gets hot enough to overflow I might suspect a problem other than a fan clutch. But I would start there.
Big Jim

 

[bronco2blue]

That word bothers me. By temporary do you mean you do not have advance in the timing?
Did the engine overheat before the spout problem?
If it gets hot enough to overflow I might suspect a problem other than a fan clutch. But I would start there.
Big Jim

I'm not entirely sure. He said that he grounded the spout circuit and removed the spout connector. Would that delete the timing advance? Ever since he did this the truck has been much more sluggish, but drives OK and without any CEL's.

I'll go ahead and replace the fan clutch for starters.

 

[RonD]

I assume 4.0l engine with EDIS module

EDIS module is autonomous, it can run the spark timing on its own with no connection to the computer, BUT....................
It isn't very good at advancing the spark because all it has to base the advance on is "after the fact" RPM increases, so it is behind in driver input, vacuum advance distributors gave spark advance a "heads up" because when driver opened throttle vacuum dropped and spark could advance with and just ahead of RPM increase.

That's the purpose of the SPOUT(spark out of computer)
EDIS module sends the computer the PIP signal, the base spark timing and when #1 is at TDC, this is how the computer times Fuel Injectors, this signal comes to the EDIS module from the CKP(crank position) sensor.

The computer has an important driver input sensor, the TPS(throttle position sensor), this takes the place of a vacuum advance(and accelerator pump on carb), the computer uses the SPOUT connection to to tell the EDIS module to advance or retard the spark and by how much, based on TPS data from driver.

No, this wouldn't cause overheating, the sluggishness you report is because spark timing is not being advanced ahead of the RPM to give you normal power curve, you need to find the problem and get the SPOUT hooked up again.

Good read here on EDIS: http://www.dainst.com/info/edis/edis.html

The SPOUT name is from the older TFI system, with EDIS it is called SAW