Overheating at idle

[Maniak]

If they carry them for your rig.. grab the hayden severe duty fan clutch. It is a tighter fan clutch and you need every bit of help you can in Az summers. I upgraded to the server duty clutch when the old one had issues. It would heat up getting onto the freeway and of course in stop/go traffic in summer..

If you don't get the sever duty, at least get a thermal, I tried the non thermal clutch (trying to get extra mpg) and all I got for my trouble was a fan clutch that would over heat.. never tried another non thermal one.

~Mark

 

[nole99]

As luck would have it I grabbed a severe duty one .... I wanted to see if I could grab the one off my 5.0 mounty but that bolt wasn't moving and I didn't have time to mess with it

Preliminary results are in ... I can manipulate the fan clutch to engage and dissengage ... its been running about 25 min hood down ac on ... every time it gets up near half on the temp gauge the fan clutch kicks on and the gauge falls a little under ...

we'll see how she does under circumstance ... have some work I gotta do first tho

 

[gijoecam]

When the engine is hot or cold the resistance on the fan when spinning by hand does not change

There's the giveaway right there. When hot, it should not spin freely.

Preliminary results are in ... I can manipulate the fan clutch to engage and dissengage ... its been running about 25 min hood down ac on ... every time it gets up near half on the temp gauge the fan clutch kicks on and the gauge falls a little under ...

That's a little odd... it shouldn't get that warm before it starts to engage... There really should be plenty of cooling capacity at idle to cool the engien, even with everything running. Even in 110+ temps here in Deetroit, I've never seen the temp gauge deviate from its normal spot (except for the time the thermostat was stuck part-way open, causing it to overheat).

 

[nole99]

Ok ... sooo Fan clutch did not solve all issues

After a 30 min drive it was fine ... until it sat at idle for about 15 min then bammm the temp climbed almost to 3/4 of the way ... I love how the engineers at ford designed a system so that as it gets hotter they rev the engine higher to spin the fan faster ... kind of an oxy moron

Leaning towards a plugged radiator ... still no loss of coolant or full on overheat ... was fine driving on the freeway with 99 ambient temp today ... ahhhh

Sooo today I pulled out the Less than a year old, 2 row visteon from my 5.0 pile scrap Mounty ... cleaned her up ... and am gonna mount her in the 4.0 sport .... Should drop right in by my all my measurements ... and give me some extra cooling capacity

She's sitting with some flush in it now ... if I get to it tonight ... great ... if not ... I'm off tomorrow

Will update

 

[RockyMtnHigh]

Ok ... sooo Fan clutch did not solve all issues

After a 30 min drive it was fine ... until it sat at idle for about 15 min then bammm the temp climbed almost to 3/4 of the way ... I love how the engineers at ford designed a system so that as it gets hotter they rev the engine higher to spin the fan faster ... kind of an oxy moron

Leaning towards a plugged radiator ... still no loss of coolant or full on overheat ... was fine driving on the freeway with 99 ambient temp today ... ahhhh

Sooo today I pulled out the Less than a year old, 2 row visteon from my 5.0 pile scrap Mounty ... cleaned her up ... and am gonna mount her in the 4.0 sport .... Should drop right in by my all my measurements ... and give me some extra cooling capacity

She's sitting with some flush in it now ... if I get to it tonight ... great ... if not ... I'm off tomorrow

Will update

My bet is on the rad being blocked. Pull it and put a trouble light to it. If you can't see light through it, or the fins are all bent down, it probably can't pull enough air to do it's job.

 

[nole99]

My bet is on the rad being blocked. Pull it and put a trouble light to it. If you can't see light through it, or the fins are all bent down, it probably can't pull enough air to do it's job.

Yeah ... I think there is internal blockage too ... was a bunch of rubber stop leak gunk up at the top when I first flushed the system

Prolly get it swapped tomorrow

 

[BrianDye]

If it were me, id really look into getting an electrical fan, so theres no mechanical trying to keep the engine cool, when the engine gets to a certain temp, boop the fan comes on, i think your fan might not be spinning or something, because when your moving the air can get pushed through the engine compartment just wind wise, but when sitting, your depending alot on your fan, if its not the radiator or hoses, thats your next bet, even though id try that first, theyre only about 120$

 

[nole99]

If it were me, id really look into getting an electrical fan, so theres no mechanical trying to keep the engine cool, when the engine gets to a certain temp, boop the fan comes on, i think your fan might not be spinning or something, because when your moving the air can get pushed through the engine compartment just wind wise, but when sitting, your depending alot on your fan, if its not the radiator or hoses, thats your next bet, even though id try that first, theyre only about 120$

I put in a brand new fan clutch and rpm tested it ... it is engaging as designed

Too many stories of electrical fan issues ... in Phoenix temps will hit 120 so not so sure I want to take a chance on an electrical ... seeing I drive about 200 miles or more a day with AC running a good chunk of it

 

[gijoecam]

When moving, you don't even need a fan in most vehicles. My F-150 has electric fans... Towing a 3500lb camper with 1000 lbs of junk in the bed, the temp never wavers even with the fans off. (I can monitor the temp in the gauge cluster)

I would agree that it sounds like a plugged radiator. Given that you found stop-leak in it, I'd say that's a decent place to start for sure. While you've got the system drained, I'd take another look at the thermostat... I've seen them fail to fully open and stick even brand new right out of the box. It could be that there's enough extra airflow through the engine bay when you're moving to keep the engine temps down...

But since you've got the radiator, I'd go ahead and throw it in for kicks... Can't make it any worse...

 

[nole99]

Sooooo ... I guess the moral of the story is that when you buy a used vehicle ... ya never know what you'll find

So I pulled the radiator ... that black finish ... apparently was painted on with a rattle can and done without cleaning the radiator first ... serious crud in there

Not to mention the fins on this single row that came out were really tight to start with

The double row that I put in from the 5.0 mounty had much more space between the fins.

The Double row from the Mounty bolted right in stock ... the only issue had was the fan shroud ... the one from the Mounty was about a 1/2 in narrowed so I opted to use the one from the 4.0 ... I had to remove the lower clip on one side because it was a little to low ... I tried to notch it but it snapped off ... should have use the dremel ...lol

What I did was drill 2 small holes in the bottom of the shroud and used zip ties to mount it through the holes in the bottom of the radiator bracket

Got it burped I think and will do some more driving this afternoon and see how it is ... was ok yesterday so crossing fingers

I took a bunch of pics and will do a full write up now that I replace the entire cooling system minus the heater core ... happy days!

 

[jlsparky7]

Awesome man. Glad that its sorted out.

The stop leak probably seized the thermostat closed so that was just a part of the problem.

 

[nole99]

Thanks to EVERYONE for their insights and suggestions!

Problem totally solved ... no issues now... runs a little under half way up the temp gauge .. no more increased engine rev to spin the fan ... no more rising temps ... driving like a dream

At the end of the game I replaced the following

Radiator
Fan Clutch
Water Pump
Thermostat
Thermostat Housing
Sensor
Thermostat
Hoses

Under 500 spent and a whole new cooling system ... most of that was in the pice of crap plastic therm housing unit that the previous owner had cracked... can't complain as I've only had it a few weeks and I now have the piece of mind knowing the cooling system should be good to go for awhile seeing I'm in good ole hot ass AZ

Full write up with pics on the whole system will be done in few days and will be linked here

 

[jlsparky7]

Thanks to EVERYONE for their insights and suggestions!

Problem totally solved ... no issues now... runs a little under half way up the temp gauge .. no more increased engine rev to spin the fan ... no more rising temps ... driving like a dream

At the end of the game I replaced the following

Radiator
Fan Clutch
Water Pump
Thermostat
Thermostat Housing
Sensor
Thermostat
Hoses

Under 500 spent and a whole new cooling system ... most of that was in the pice of crap plastic therm housing unit that the previous owner had cracked... can't complain as I've only had it a few weeks and I now have the piece of mind knowing the cooling system should be good to go for awhile seeing I'm in good ole hot ass AZ

Full write up with pics on the whole system will be done in few days and will be linked here

Sweet. Great job troubleshooting!

 

[nole99]

Sweet. Great job troubleshooting!

Couldn't have done it without you guy's help!

It was really interesting to see what swapping out each item did to help get me back to normal ... every step brought me a little closer!

Thanks again ... off to work!

 

[bronchole]

Since you have solved your problem I'd like to hyjack your thread.

I am the new owner of a 1992 Explorere 4x4. I have recently replaced the radiator with a 2 row unit, all of the hoses and the thermostat. Cooling works great normally except when near idel and running the A/C. Specifically I ran a section of Majave road in the So. California desert last weekend and while going around 15 MPH with the A/C on and in 4WD thru mild sand the temperature would go up to around 3/4 (near the A), it would be hot enough to disengauge the A/C. I tried this speed in 4hi and 4lo and in various gears with no noticable differences. The only thing I haven't really looked closely at is the fan clutch.

What do ya think?

Dan

 

[nole99]

Since you have solved your problem I'd like to hyjack your thread.

I am the new owner of a 1992 Explorere 4x4. I have recently replaced the radiator with a 2 row unit, all of the hoses and the thermostat. Cooling works great normally except when near idel and running the A/C. Specifically I ran a section of Majave road in the So. California desert last weekend and while going around 15 MPH with the A/C on and in 4WD thru mild sand the temperature would go up to around 3/4 (near the A), it would be hot enough to disengauge the A/C. I tried this speed in 4hi and 4lo and in various gears with no noticable differences. The only thing I haven't really looked closely at is the fan clutch.

What do ya think?

Dan

Did you have these issues prior to making your repairs?

What happens if you turn the heat on? Does the temp drop? If so you probably have air in the system and need to "burp" it out

How long into or idle or slow speed before your temp starts to rise?

Could very well be your fan clutch

You will probably get even more replies if you start a new thread with your specifics


As an aside ... system has been running great ... gauge doesn't so much as flinch