Yes, and a get a plastic fan too. Cruiser outfitters would be able to hook you up with new stuff for sure.
Radiator overflow, overflowing (1 Viewer)
- Thread starter wchevron
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
I like my OEM fan with no clutch - less to go wrong. In the winter I have a piece of old tent floor canvas on paracord hung in on the front of the radiator. I usually have it covering the lower 1/3 to 1/2 so it will run at normal temp. There have been times in low range low that required complete removal of the curtain to run normal. Knots and paracord make easy adjustments. At one time I was going to make an adjustable from inside the cab sheet metal shroud, seems like a lot of work for something that seldom needs adjustment.
Skreddy
SILVER Star
I’m with Mark on that fan; I hate them. I’d source a plastic direct drive one at minimum. The only downside to the direct drive over the clutch fan is it’s always going so your engine will sound louder.
- Joined
- Apr 14, 2004
- Threads
- 1,468
- Messages
- 36,683
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
I sell those parts. It’s kind of disappointing how readily I am looked to for tech, and how easily I am overlooked as a parts resource.
Last edited:
mattressking
10 digits to freedom
Since the fan is locked at all times and intact, replacing the fan currently is only for peace of mind, it will not resolve your issue. Cap is a cheap initial check, but high probability it is NOT your fault. Coolant is at boiling point because it either
A. can't move (thermostat)
B. Can't move again (waterpump failed). you'd usually see it weeping out of weep hole
C. Clogged radiator (which can easily be tested by putting hand on lower hose and feel for temp).
D. And most unfortunately but common for higher mileage engines - Headgasket failure.
If you drive it again for testing as it gets hot, turn heater on to circulate coolant and see if it stabilizes (until all coolant becomes too hot again).
A. can't move (thermostat)
B. Can't move again (waterpump failed). you'd usually see it weeping out of weep hole
C. Clogged radiator (which can easily be tested by putting hand on lower hose and feel for temp).
D. And most unfortunately but common for higher mileage engines - Headgasket failure.
If you drive it again for testing as it gets hot, turn heater on to circulate coolant and see if it stabilizes (until all coolant becomes too hot again).
- Thread starter
- #26
Was just on the road. Gauge went up to the hash mark just below the H again. While on the highway, I opened up the heater valve and turned on the fan. Temp climbed over the hash mark. Turned the fan off and it went back down to the hash mark. Supposed to be cooler over the weekend, 80's, so will see where the temp is on those days. May be wrong but I'm pretty sure it stays below the hash mark on the days below 90*
mattressking
10 digits to freedom
Just to confirm - not the fan switch, just the heat control lever. FJ40s do not function like a modern car, turning fan on doesn’t actuate the heater valve.
So make sure that you pulled the heater lever all the way out and confirmed the valve opened on firewall in engine bay?
So make sure that you pulled the heater lever all the way out and confirmed the valve opened on firewall in engine bay?
- Joined
- Apr 14, 2004
- Threads
- 1,468
- Messages
- 36,683
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
I disagree with this assessment. That metal fan is not penetrating the shroud sufficiently, even as a static observation. As it flexes, it gets worse.
While it would be interesting as an experiment to add spacers to it until it has enough penetration, I certainly wouldn’t suggest adding more fulcrum to that ticking time bomb.
30 years ago I had a customer come in with his broken water pump that he had bought from me, telling me that I owed him another one, along with a radiator to replace the one that got chewed up when it broke.
When he showed me the flex fan and spacer that were still attached to the mounting flange of the pump, it was a challenge for me not to laugh. But of course, he didn’t know that it wasn’t stock.
mattressking
10 digits to freedom
Unfortunately I disagree with this assessment, fan location on the shroud is plenty sufficient. Fan shroud, although very effective, is not necessary and will not impede nor cause overheating. The only time I've experienced true disruption is on 1960s econoline and A-series vans where the radiator sits in the dog box and requires a direct force of air to provide flow. Fan shrouds, on properly functioning cooling systems, aid heavily, but lack-of will not cause overheating if they aren't in place on viscous fans systems, especially direct drive.I disagree with this assessment. That metal fan is not penetrating the shroud sufficiently, even as a static observation. As it flexes, it gets worse.
While it would be interesting as an experiment to add spacers to it until it has enough penetration, I certainly wouldn’t suggest adding more fulcrum to that ticking time bomb.
30 years ago I had a customer come in with his broken water pump that he had bought from me, telling me that I owed him another one, along with a radiator to replace the one that got chewed up when it broke.
When he showed me the flex fan and spacer that were still attached to the mounting flange of the pump, it was a challenge for me not to laugh. But of course, he didn’t know that it wasn’t stock.
Definitely skip the metal/direct fan though, plastic clutch fan is a great upgrade for driving.
- Thread starter
- #30
Pulled the heater valve out. Waited a few minutes then pulled the fan knob out. Seemed to be after the fan came on the temp rose. Turned the fan off and temp dropped within 5 minutes. My heater valve cable opens the valve just fine. Pushing it in doesn't close the valve. Need to open the hood and close it manually.
Sounds to me like you've allowed a bubble of air to move.
Have you tried burping it out?
- Thread starter
- #32
The cable housing detached from the knob so when you push the knob in, the cable housing slides and doesn't give the cable enough friction to force the valve closed. Was going to try to get a clamp on the housing to lock it into place but keep forgetting about it. Once fall comes I open the valve and leave it open until I put the truck away for the winter. Then in the spring I manually close it when it starts to get warm out. Only have to close it manually a couple of times a year so I've left it for now.
- Thread starter
- #33
Left you a voicemail earlier today.I sell those parts. It’s kind of disappointing how readily I am looked to for tech, and how easily I am overlooked as a parts resource.
- Joined
- Apr 14, 2004
- Threads
- 1,468
- Messages
- 36,683
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
I’m in purgatory today, sanding ceiling plaster. I will be back in the office tomorrow.
Mark will hook you the $@#& up!I sell those parts. It’s kind of disappointing how readily I am looked to for tech, and how easily I am overlooked as a parts resource.
Ditch the flex fan and put a proper fan clutch and plastic blade (more and better airflow) back on it. All parts we can easily assist with at Cruiser Outfitters. I may have missed it, is the pump new?
"noticed the radiator overflow was gurgling and some antifreeze had leaked out."
I do not understand this observation. If you have the OEM cylindrical overflow tank, isn't the radiator overflow hose connected to the bottom of the overflow tank? And the relief tube attached to the top of the overflow tank only "leaks" when the overflow tank is full?
"Let it cool down and took the cap off. Coolant is right up to the top. Took the cap off the overflow tank. It's empty. Should I fill it to the Low level or Full level?"
So, the overflow tank that was so full it spit overflow onto the ground, is empty when things cool off? The radiator is full, but the tank is empty? Are you saying the full overflow tank got sucked back into the radiator, and the radiator was full to the neck of the radiator cap?
Is there any chance your overflow tank isn't plumbed properly?
Fan blades and airplane wings have a lot in common. Blades and wings cut through air, the resulting higher pressure on one side pushing air (bottom of wing, engine side of fan) causing a difference in pressure, lower pressure on the other side (top of wing, radiator side of fan.)
From this pressure difference, the air below the wings (blades) rolls up and wraps around the top of the wing (blade), causing a whirlwind named a wingtip vortex. In other words, some of the air pushed by the blade towards the engine rolls back and flows into the low pressure side of the blade.
According to NASA, "The effect of these vortices is increased drag and reduced lift that results in less flight efficiency and higher fuel costs." For a fan blade, this means less air flow through the radiator. Airplanes reduce this vortex using winglets flaring upwards on the end of the wings.
A properly positioned fan shroud would reduce this "wingtip vortex", improving mass flow through the radiator for better cooling. This allows for less aggressive fans, which use less parasitic horsepower to turn a mechanical fan.
On the other hand, more hp hungry aggressive fans don't need shrouds.
If shrouds weren't important, why would automakers use them on every car they build?
- Thread starter
- #39
When I shut the truck off, then heard the gurgling. Opened the hood. Below the overflow tank the frame was damp, side of the battery was damp and there were a couple of drops of antifreeze on the ground. To be honest, I'm not sure if the overflow tank had anything in it to begin with. Never looked in it before. There is an overflow hose coming from the radiator to the bottom of the overflow tank. Not sure if any antifreeze boiled over and entered the overflow tank as steam and since the tank was/might have been empty, the steam blew through the relief hose?"noticed the radiator overflow was gurgling and some antifreeze had leaked out."
I do not understand this observation. If you have the OEM cylindrical overflow tank, isn't the radiator overflow hose connected to the bottom of the overflow tank? And the relief tube attached to the top of the overflow tank only "leaks" when the overflow tank is full?
"Let it cool down and took the cap off. Coolant is right up to the top. Took the cap off the overflow tank. It's empty. Should I fill it to the Low level or Full level?"
So, the overflow tank that was so full it spit overflow onto the ground, is empty when things cool off? The radiator is full, but the tank is empty? Are you saying the full overflow tank got sucked back into the radiator, and the radiator was full to the neck of the radiator cap?
Is there any chance your overflow tank isn't plumbed properly?
Once the radiator had cooled off, I opened the cap and looked inside and the antifreeze was up to the neck so if it did release any antifreeze/steam to the overlfow it couldn't have been much.
I added some antifreeze to the overflow tank that night. Up to the Low line. Drove around yesterday, hot again 90's. Couple of times the temp gauge got up to the upper hash mark. No gurgling when I shut off the truck at any time. When I got home last night and the truck cooled off, checked the overflow tank and it was empty? Not sure when the added antifreeze went. Didn't notice any wet spots under the truck all day. Rain next 2 days so won't be driving it. Going to be cooler on the weekend so will keep an eye on the temp gauge. Pretty sure on the cooler days it stays almost in the center of the temp gauge.
pb4ugo
SILVER Star
You may have had air in the system and when it cooled down it sucked in more a/f.
Fill the res to the lower line again and cycle it again.
Fill the res to the lower line again and cycle it again.
