Drove from Corpus Christi back to Oklahoma Friday night. Got to I35W in Fort Worth and ran into a total parking lot. Nothing was moving for 10 minutes. Was looking around and noticed a bunch of cars had their windows down, the outer thermostat was showing 101F outside. Seemed strange. Noticed the truck started idling a little higher than normal. AC was blowing cold. I was facing North so no air was going through the front end. I then noticed the engine temps started climbing and climbing and climbing....uh ohhhhhhhhh. Dawned on me why the other cars had their windows down, they probably had the heat cranked up to try and keep the engine from overheating. Needle was getting close to the red. Made a sharp turn and managed to get off of the interstate, but ran into some stop lights, but moving none the less, slowly...the needle started going down to normal again. My question, would this be considered "normal"? No air, outside temp is above 100, sitting with a bunch of other cars, AC on, have been driving for 8 hours. Truck has NEVER done that and it gets hot here in Oklahoma, but I've haven't seen the temp gauge even move off of normal ever. I've flushed the radiator out about two years ago and the antifreeze was still good to go.
almost overheated....wondering....
- Thread starter Schmoe
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Is the truck's cooling fan electronic or clutch-driven?
Modern cars technically shouldn't overheat like that. If the radiator's original from '01, it may have trouble keeping up when hot idling.
I'd also replace the rad cap. It likely isn't keeping the proper pressure after all of these years.
Modern cars technically shouldn't overheat like that. If the radiator's original from '01, it may have trouble keeping up when hot idling.
I'd also replace the rad cap. It likely isn't keeping the proper pressure after all of these years.
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Sometimes, older radiators, not to mention older blocks/heads, get scale built up that impedes heat transfer.
Might be time for a good flush, followed by a new radiator...
Sometimes older pumps wear out, the impellers corrode a bit, and they move less fluid, so, while they don’t leak, they really need to be replaced.
So, if the radiator doesn’t fix it, a new pump might.
Might be time for a good flush, followed by a new radiator...
Sometimes older pumps wear out, the impellers corrode a bit, and they move less fluid, so, while they don’t leak, they really need to be replaced.
So, if the radiator doesn’t fix it, a new pump might.
If the rad is old it's probably got a ton of crud built up on the fins which may be restricting air flow when stopped in traffic.
Spray some degreaser on the fins and rinse it with plenty of water too.
Spray some degreaser on the fins and rinse it with plenty of water too.
Originally Posted By: Schmoe
I've flushed the radiator out about two years ago and the antifreeze was still good to go.
I've never heard of a radiator going bad with age, how gross was it when you flushed it? I've only owned cars with electric fans but you should check your fan. Nothing says overheating at idle like a bad cooling fan, I have had a similar experience on the highway.
Originally Posted By: Schmoe
Might be time for a good flush, followed by a new radiator...
Sometimes older pumps wear out, the impellers corrode a bit, and they move less fluid, so, while they don’t leak, they really need to be replaced.
I thought when the water pump was bad, you overheat when you are moving, especially on the highway.
I've flushed the radiator out about two years ago and the antifreeze was still good to go.
I've never heard of a radiator going bad with age, how gross was it when you flushed it? I've only owned cars with electric fans but you should check your fan. Nothing says overheating at idle like a bad cooling fan, I have had a similar experience on the highway.
Originally Posted By: Schmoe
Might be time for a good flush, followed by a new radiator...
Sometimes older pumps wear out, the impellers corrode a bit, and they move less fluid, so, while they don’t leak, they really need to be replaced.
I thought when the water pump was bad, you overheat when you are moving, especially on the highway.
Start with a cap and clean. Carry a couple jugs of water.Check belt tension. A 17 yr old Ford probably has several marginal issues combined with the heat and traffic. It may never happen again,or it is the start of something. I love how inter net guys spend your money.
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Nick1994
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My guess is the fan clutch is worn out. 101 isn't that hot. It may feel hot because of humidity but that's not very hot. It hit 119-120 here last year, I could idle my car outside all day, shouldn't run hot.
Fan clutch (assuming not electric and also mentioned earlier) would be my guess.
Black asphalt here can easily reach 165°F. Easy to measure with an IR thermometer. In addition, the solar heat index can easily reach > 135°F on sunny days in the afternoon when the Sun is West of the meridian. When you're stuck in traffic, all of that surface heat is rising, heat-soaking your engine compartment from below. Complicating matters is hot, humid exhaust from the vehicle in front of your radiator as well as on multiple sides.
This is a perfect stress-test for any cooling system.
Rather than driving when the temp gauge is near-red, it's best to just pull out of traffic, turn off the engine, open the hood and wait about 20 min. With the hood open, now all of that heat has somewhere to go rather than being trapped.
This is a perfect stress-test for any cooling system.
Rather than driving when the temp gauge is near-red, it's best to just pull out of traffic, turn off the engine, open the hood and wait about 20 min. With the hood open, now all of that heat has somewhere to go rather than being trapped.
My guess would pinpoint the fan as well, probably coupled with slightly reduced radiator efficiency over the years. I have noticed on my car, which has an electric fan, runs hotter with the ac off. This is solely because the fan isn’t running constantly. I have noticed this on two vehicles. I have also noticed in my truck that the ac runs noticeable warmer in stop and go traffic because of reduced condenser efficiency. That truck when new never had that problem and all the years of bugs and dirt and bent fins have reduced the efficiency.
With the truck nearly overheating like that, if you stood outside your driver's door you should feel lots of hot air coming from the under-motor area. This shows the fan blowing, the radiator giving off heat, and the water pump getting coolant to the radiator properly. Even in hot outside air you should feel the even hotter coming from your truck.
My first suspicion is the fan clutch, it should lock up good and sound like a school bus when you get just above idle. You'd have noticed it on your couple-block cool-down cruise.
My first suspicion is the fan clutch, it should lock up good and sound like a school bus when you get just above idle. You'd have noticed it on your couple-block cool-down cruise.
Nick1994
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Originally Posted By: sleddriver
Black asphalt here can easily reach 165°F. Easy to measure with an IR thermometer. In addition, the solar heat index can easily reach > 135°F on sunny days in the afternoon when the Sun is West of the meridian. When you're stuck in traffic, all of that surface heat is rising, heat-soaking your engine compartment from below. Complicating matters is hot, humid exhaust from the vehicle in front of your radiator as well as on multiple sides.
This is a perfect stress-test for any cooling system.
Rather than driving when the temp gauge is near-red, it's best to just pull out of traffic, turn off the engine, open the hood and wait about 20 min. With the hood open, now all of that heat has somewhere to go rather than being trapped.
It shouldn't have any issue with it in the first place. Back in 2001 when this truck was new, it should be able to sit and idle in Death Valley and be fine. It should be able to do that now too, once the cooling system issues are addressed.
Black asphalt here can easily reach 165°F. Easy to measure with an IR thermometer. In addition, the solar heat index can easily reach > 135°F on sunny days in the afternoon when the Sun is West of the meridian. When you're stuck in traffic, all of that surface heat is rising, heat-soaking your engine compartment from below. Complicating matters is hot, humid exhaust from the vehicle in front of your radiator as well as on multiple sides.
This is a perfect stress-test for any cooling system.
Rather than driving when the temp gauge is near-red, it's best to just pull out of traffic, turn off the engine, open the hood and wait about 20 min. With the hood open, now all of that heat has somewhere to go rather than being trapped.
It shouldn't have any issue with it in the first place. Back in 2001 when this truck was new, it should be able to sit and idle in Death Valley and be fine. It should be able to do that now too, once the cooling system issues are addressed.
Have you tried cleaning out your condenser and radiator? Matco sells a blowgun for $50 or so, but I made my own.
I use a hose adaptor to 1/2 inch in copper, a section of 1/2 copper pipe, and a 1/2 inch copper cap.
I sweat all the pieces together and cut a slit in the cap with a cut off wheel. I attach it to a standard hose gun with external threads.
Water does a great job of cleaning bugs and Willow out
I use a hose adaptor to 1/2 inch in copper, a section of 1/2 copper pipe, and a 1/2 inch copper cap.
I sweat all the pieces together and cut a slit in the cap with a cut off wheel. I attach it to a standard hose gun with external threads.
Water does a great job of cleaning bugs and Willow out
Originally Posted By: eljefino
With the truck nearly overheating like that, if you stood outside your driver's door you should feel lots of hot air coming from the under-motor area. This shows the fan blowing, the radiator giving off heat, and the water pump getting coolant to the radiator properly. Even in hot outside air you should feel the even hotter coming from your truck.
My first suspicion is the fan clutch, it should lock up good and sound like a school bus when you get just above idle. You'd have noticed it on your couple-block cool-down cruise.
+1
With the truck nearly overheating like that, if you stood outside your driver's door you should feel lots of hot air coming from the under-motor area. This shows the fan blowing, the radiator giving off heat, and the water pump getting coolant to the radiator properly. Even in hot outside air you should feel the even hotter coming from your truck.
My first suspicion is the fan clutch, it should lock up good and sound like a school bus when you get just above idle. You'd have noticed it on your couple-block cool-down cruise.
+1
Need to do some diagnosing. I have seen electric fans that don't work. The fan either goes out or the relay needs replaced. The car never overheats when you are driving, but once you get stuck in traffic, it will never cool down. If it has a mechanical fan, I have seen the clutches in them wear out and your fan doesn't work properly. Start with the fans. If they are working properly, then work your way back. Bad water pump, bad radiator, coolant needs flushed, thermostat needs replaced.
Originally Posted By: hansj3
Have you tried cleaning out your condenser and radiator? Matco sells a blowgun for $50 or so, but I made my own.
I use a hose adaptor to 1/2 inch in copper, a section of 1/2 copper pipe, and a 1/2 inch copper cap.
I sweat all the pieces together and cut a slit in the cap with a cut off wheel. I attach it to a standard hose gun with external threads.
Water does a great job of cleaning bugs and Willow out
I just did this, if you are going to pull the nose/grill from your car you might as well get a can of coil cleaner. My condenser almost completely covered my radiator so you might want to look elsewhere.
Have you tried cleaning out your condenser and radiator? Matco sells a blowgun for $50 or so, but I made my own.
I use a hose adaptor to 1/2 inch in copper, a section of 1/2 copper pipe, and a 1/2 inch copper cap.
I sweat all the pieces together and cut a slit in the cap with a cut off wheel. I attach it to a standard hose gun with external threads.
Water does a great job of cleaning bugs and Willow out
I just did this, if you are going to pull the nose/grill from your car you might as well get a can of coil cleaner. My condenser almost completely covered my radiator so you might want to look elsewhere.
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Im guessing you need a new clutch for your clutch fan. At that point in traffic with you engine heated up your clutch fan should have been locked up. When these clutch fans lock up they move A LOT of air!! Like was said earlier anything above idle you will hear that fan and its unmistakable.
Your idle speed was going up in an effort to make the mechanical fan spin faster and move more air to keep the engine cooled. If the fan clutch is working right, under these conditions, your fan should move a huge amount of air. You also would not mistake the sound of the fan moving that much air - think of the sound of Mack truck fan on a hot day...
If you did't hear that, start with the fan clutch (and I'd recommend an OEM one - just based on experience with aftermarket clutches...)
If you did't hear that, start with the fan clutch (and I'd recommend an OEM one - just based on experience with aftermarket clutches...)
Thanks for that. It's is still factory mechanical clutch fan. Didn't even think about looking at that. I had thought the increase in RPM's were in response to the cooling system not being very effective right then. When I did flush it out, it was pretty dang gunky. Got this truck from my Dad when he passed and he really didn't do anything to it. Radiator/condenser fins are clean and clear. Fan does work....when I first crank it up, it does make a Mack truck sound at first then settles down, but I didn't hear it, or listen for it, that night. My only concern was to somehow get some air moving through the engine. I knew if I could get it moving, I'd be alright. Been driving all day with 100 plus degrees and about 90 plus humidity and AC blowing and that temperature gauge didn't even move. Tells me water pump is OK...I'll flush that radiator out again and then let it idle for a while when we start hitting 100 plus here in Oklahoma to see if that fan is pushing a lot of air. I haven't checked for clearance, but is that fan clutch setup removable inside the engine bay? I don't want to have to take off that whole front end to get to it.
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