Do you still have the OEM rock guard that sits below the radiator above the steering stabilizer? I know alot of them go missing with time. I don't know about the 80, but I know a similar plate made a big difference on an old car I had.
Overheating help and fan clutch advice
- Thread starter hammerheadfistpunch
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- Thread starter
- #42
Yes it's on there
Last summer I was having overheating issues. They popped up on a camping trip towing our pop-up camper. Below 50 mph, and keeping the rpms below 3k, I could keep the temps reasonable. But with the tires on my truck, the PA hills, and the camper in tow, that was a tough assignment. It was around 90* that day.
I replaced the clutch fluid with 10k fluid. Took care of all over heating issues. Obviously we do not get the heat you guy in the desert do, but a weak fan clutch with overheat one of these rigs in a hurry.
I replaced the clutch fluid with 10k fluid. Took care of all over heating issues. Obviously we do not get the heat you guy in the desert do, but a weak fan clutch with overheat one of these rigs in a hurry.
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Just got back from a Forest Service SO/Regional personal tour, their request is one of the few reasons that would get us out in the desert this time of year. 
Anyway, heading for a high of 104F, full sun and dry, at least they chose the "coolest" day of the week, so there is that.
On the highway saw a high of 192F, mostly between 185-190F, on slight grades, selecting 3rd gear bringing the RPM up to ~3000rpm, drops the temp ~4F. On the trail, including some long sand wash runs saw a high of 196F, but again, mostly between 185-192F. The hot point was airing up and debriefing with the dignitaries, it sat idling, full sun, couple of doors open, with the A/C blasting, jumped back in was 200F, shortly after pulling away, right back down.
Mine is pretty simple, mostly stock, hood not cut, cheap TYC rad, tuned clutch (don't recall what is on it) dealer thermostat, removed the pusher fan that was on it. Has 37" tires over 4.10 gears, so likely differs from most on the highway part? For what we do, I'm a big fan of simple, doesn't take any tricks, all of the airflow devices in place, well tuned clutch and an efficient radiator, gets the job done.
Anyway, heading for a high of 104F, full sun and dry, at least they chose the "coolest" day of the week, so there is that.On the highway saw a high of 192F, mostly between 185-190F, on slight grades, selecting 3rd gear bringing the RPM up to ~3000rpm, drops the temp ~4F. On the trail, including some long sand wash runs saw a high of 196F, but again, mostly between 185-192F. The hot point was airing up and debriefing with the dignitaries, it sat idling, full sun, couple of doors open, with the A/C blasting, jumped back in was 200F, shortly after pulling away, right back down.
Mine is pretty simple, mostly stock, hood not cut, cheap TYC rad, tuned clutch (don't recall what is on it) dealer thermostat, removed the pusher fan that was on it. Has 37" tires over 4.10 gears, so likely differs from most on the highway part? For what we do, I'm a big fan of simple, doesn't take any tricks, all of the airflow devices in place, well tuned clutch and an efficient radiator, gets the job done.
I have a question because I battle this problem living in west texas well. Does anyone make a straight clutchless fan for these vehicles?
- Thread starter
- #46
To be honest I have to wonder if a 30k or 50k weight modded clutch isn't basically just that.
That's why I'm asking . what's the point of all of these mods when we could just design a straight fan and be done with it.
inkpot
SILVER Star
You could certainly mount a non- clutch style fan on it, but you would need about a 6” spacer to get it properly spaced in the shroud for effective cooling.
And NO, a heavily juiced fan does not lock up anywhere close to 100%.
And NO, a heavily juiced fan does not lock up anywhere close to 100%.
Can the black clutch be modded similar to the blue one .I have a black one in the garage that I may just swap the oil in and try it if so.
inkpot
SILVER Star
The older black clutch is a very strong unit. 10,000-12,000 CST silicone should make it pretty aggressive.
Maybe I should put it back on then .replace r it with a stock blue fan. But it still gets a little hot. At highway speeds .Idk . I can pull the blue one off and mod it i guess or just order one from witsend and be done with it .
I ran 30k fluid in my stock fan clutch and it worked pretty good. 60K fluid made a big difference. 7 bucks for a bottle of Lucas silicon diff fluid. No need to mod a solid fan clutch. Or get a cheap napa fan clutch and put a couple of bolts through it.
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Go for it, there are likely off the shelf parts available.
The reason that just about every belt driven fan, for what the last 40yrs, has a clutch, because they have significant advantages. A fan designed to work/survive red line rpm will be inefficient at idle. The slip of the clutch allows the shaft (water pump) to be turned faster that would otherwise be possible. This nets a setup that turns the fan faster at idle and never reaches full rpm, so runs more consistently close to the optimum design speed.
lcgeek
Glad to meet you!
Just got back from a Forest Service SO/Regional personal tour, their request is one of the few reasons that would get us out in the desert this time of year.
On the highway saw a high of 192F, mostly between 185-190F, on slight grades, selecting 3rd gear bringing the RPM up to ~3000rpm, drops the temp ~4F. On the trail, including some long sand wash runs saw a high of 196F, but again, mostly between 185-192F. The hot point was airing up and debriefing with the dignitaries, it sat idling, full sun, couple of doors open, with the A/C blasting, jumped back in was 200F, shortly after pulling away, right back down.
Mine is pretty simple, mostly stock, hood not cut, cheap TYC rad, tuned clutch (don't recall what is on it) dealer thermostat, removed the pusher fan that was on it. Has 37" tires over 4.10 gears, so likely differs from most on the highway part? For what we do, I'm a big fan of simple, doesn't take any tricks, all of the airflow devices in place, well tuned clutch and an efficient radiator, gets the job done.
Where and how are you taking your temp reading?
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Ultra gauge, so the ECU temp sensor.
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I wouldn't run a stock fan at full shaft speed, not likely to end well!
In Israel off-road Desert Jeep with big tiers Dana 60 axles or above go to 3 step speed electrical fan custom made instead of FC fan
Cooling Fan Shoot-Out! - Engine Masters Ep. 20
Cooling Fan Shoot-Out! - Engine Masters Ep. 20
- Thread starter
- #58
UPDATE: 99% sure that my problem isn't airflow its waterflow. I've done pressure testing and there are no leaks, I've done coolant gas testing and no HG problems. I talked to @cruiserdan today at the museum and I think we've settled on the fact that the radiator is restricting water flow. Going to try and do a jmac aluminum/plastic rad and see if that helps. The main kicker here is that I wasn't overheating before the new radiator and I am now. I will report back.
inkpot
SILVER Star
Gotta price guestamate on that Jmac?
- Thread starter
- #60
*duplicate*
