Another cooling issue

[mcsteven]

OK, I read many of the posts about erratic temp, etc. Here's my issue and hoping someone can assist. :exp:

96 XLT 4.0 OHV, 4x4, 4 door, auto, etc.

All fluid levels are good, and other guages are in normal range (except fuel - it always seems to get lower). Temp guage stays steady when I'm not moving, but will rise and fall when I'm moving, especially at highway speeds. Last night, the guage went higher than normal and the CHECK GUAGES light came on. It went off very quickly as I slowed and took an exit (was only doing about 65 MPH).

When engine is running, I feel pressure in the upper radiator hose, suggesting that their is coolant flowing (or at least pressurized).

I opened the radiator cap, filled the radiator, and then ran the engine until it was at temp and made sure the radiator was still full.

The serpentine belt is tight and seems in good condition.

There are no obstructions to the radiator.

I don't see any leaks (water pump, radiator) nor do I see oil on the coolant or coolant in the oil (looking for bad head gasket).

I haven't checked the sender units yet, nor replaced the thermostat yet. Likely I'll do that this weekend.

Suggestions?

Thanks,
Marc

 

[ERUSH97XLT]

Hello,

I've had similar problems, and they haven't been resolved yet, but a small hole drilled through my thermostat has aided in burping air out of the cooling system and temperature gauge fluctuation control. As long as my temp gauge doesn't indicate overheating, I'll be ok.

Do you get a strange thumping noise through the dash?

There are some TSBs out there you may reference. A quick search will help.

ERUSH

 

[mcsteven]

...Do you get a strange thumping noise through the dash?

There are some TSBs out there you may reference. A quick search will help.

ERUSH

No thumping noises thru the dash. I'll stop by the local Ford Dealer and see if I can check out the TSBs.

 

[ERUSH97XLT]

No thumping noises thru the dash. I'll stop by the local Ford Dealer and see if I can check out the TSBs.

They're available on this forum; search for "temperature gauge fluctuation" or words to that effect.

EDIT: found one for you:

http://www.explorerforum.com/forums/showthread.php?t=64493

 

[yavapaires]

My 96 does the same fluctuation. I figure it is the thermostat due for replacement before long. Doesn't get hot, so I just keep an eye on it.

 

[Deathwish657]

Hello, Probably Re-opening this thread, but I'm curious if anyone found a solution to this yet. I've replaced the water pump, thermostat again, figuring that something went wrong with the pump, was going to replace the heater core too but tore it all apart, the core was still good so reassembled. It seems to only happy when i got the heater running for mine. I've looked around for that "Coolant Bypass Kit" no one has heard of that, found out its been discontinued.

Someone on the forums had suggested it might be one of the other components going bad but, i can't locate anything bad, possibly the power steering but thats about all.

If anyone has any suggestions, that would be awesome.

 

[yavapaires]

OK, I read many of the posts about erratic temp, etc. Here's my issue and hoping someone can assist. :exp:

96 XLT 4.0 OHV, 4x4, 4 door, auto, etc.

All fluid levels are good, and other guages are in normal range (except fuel - it always seems to get lower). Temp guage stays steady when I'm not moving, but will rise and fall when I'm moving, especially at highway speeds. Last night, the guage went higher than normal and the CHECK GUAGES light came on. It went off very quickly as I slowed and took an exit (was only doing about 65 MPH).

When engine is running, I feel pressure in the upper radiator hose, suggesting that their is coolant flowing (or at least pressurized).

I opened the radiator cap, filled the radiator, and then ran the engine until it was at temp and made sure the radiator was still full.

The serpentine belt is tight and seems in good condition.

There are no obstructions to the radiator.

I don't see any leaks (water pump, radiator) nor do I see oil on the coolant or coolant in the oil (looking for bad head gasket).

I haven't checked the sender units yet, nor replaced the thermostat yet. Likely I'll do that this weekend.

Suggestions?

Thanks,
Marc

Fan clutch?

 

[Deathwish657]

Still have the "Thumping" Noise, Asked autozone about it today, guy was saying if it gets hotter when that all happens, then gets warmer again, which i think it may have been doing so, checked it tonight, Avg Temp with max heat up was 115 Degrees. When temp Guage did the Flaucating, it was getting a reading of 137 Degrees..

They're saying it's more then likely the Heater Blend Door, so i'm going to replace that soon, then i'll confirm if thats been my issue, maybe it'd help others too, which is why i decided to share the input i got from Autozone.

 

[Deathwish657]

Yea, i think scratch that one.. Looked up the heater blend door, it ain't the problem at all since the temp control does actually function the way its supposed to, therefor not the problem.

 

[fast_dave]

mcsteven,

Try this as it's pretty cheap and basic.

The up and down temps (fluctuating) & thumping sounds like air in your cooling system.

With this in mind, fill your radiator by utilizing ONLY the overflow tank.

Every time you open the radiator cap you're introducing air into your cooling system.

Also VERY IMPORTANT - If your radiator cap is more than 3 years old, purchase a new radiator cap, as your radiator cap gasket is compressed and not offering a positive seal. That $5 radiator cap takes a LOT of abuse that you can't see ;-)

When you replace the cap you will notice how easily the old one comes off due to the gasket being compressed, and how much effort it takes to install the new one, due to the gasket being brand new...

Make sure you do NOT get a radiator cap with a lever on top - you need a closed system cap with no lever on top. Here's what you need for a '96 with an OHV:

Stant brand part number 10233

 

[joe doe]

if the temp gauge rises and falls with engine speed you have a stuck open thermostat .
it should stay pretty consistent at all times when working properly .

 

[fast_dave]

if the temp gauge rises and falls with engine speed you have a stuck open thermostat .
it should stay pretty consistent at all times when working properly .

Good catch joe_doe!

After reading your diagnosis, I re-read what the OP wrote, and noticed that says he hasn't replaced his thermostat - and looking at the temps he listed they are pretty low (115 to 137 degrees). They should at least be up at least 195 degrees.

Motorcraft #F2TZ8575A, YU3Z8575BA

Yes - give that a try!

 

[joe doe]

i been driving explorers for near 15 years now .i get it right once n awhile ...lol....explorer forum sure has been a blessing at times .

 

[mcsteven]

Good catch joe_doe!

After reading your diagnosis, I re-read what the OP wrote, and noticed that says he hasn't replaced his thermostat - and looking at the temps he listed they are pretty low (115 to 137 degrees). They should at least be up at least 195 degrees.

Motorcraft #F2TZ8575A, YU3Z8575BA

Yes - give that a try!

i been driving explorers for near 15 years now .i get it right once n awhile ...lol....explorer forum sure has been a blessing at times .

OK - OP here. I do appreciate the help, but some times (me included) we don't always read it all.

I didn't post the 115-137 readings. I also don't have the noise from under the hood.

I will try the new radiator cap. But I did fill the radiator, then ran the car with the cap off and the heater on, and filled it again as it got lower.

As a note: I've done some VERY basic car work, and that's why I can't figure out why the heat rises when the heater is on. Heat removed from the coolant usually helps to lower the engine temp. But I'm thinking it might be a thermostat issue, sticking.

Thanks everyone. Another day, and I have another issue or two. Right now I'm experiencing stuff that it seems none of us have solved except for bringing it to a "qualified service center." The cooling issue, the cylinder 5 & 6 not firing/backfiring issue, the radio on/off button not turning it off, lights out (not all of them) on the gauge part of the dash, and now an issue with the windows. Posted after using the google search slow window.

Thanks Guys,
MCS

 

[Deathwish657]

LOL, Yep.. Ford == Fix or Repair Daily. or.. Ford == Driver Returns on Foot.

Also might wanna check your Harmonic balancer.. It could be going bad, check into my other post...

http://www.explorerforum.com/forums/showthread.php?t=342677

 

[cogs]

i didn't see a post about a harmonic balancer there, just a reference to it in the last post.