Thermo fan—can I mount in front of radiator & keep viscous fan?

JohnJ78

TJ Enthusiast
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It gets very hot where I live. Is it possible to add a thermofan in front of the radiator (in front of AC condenser) while keeping the viscous fan?

I imagine most people remove the viscous fan.... but I like the idea of keeping it in case the electric one stops working.
 
Only on 110+ degree days, and only when I stop (boils over). I have replaced every single part of my cooling system, water pump, thermostat, radiator, the lot. I've checked for head gasket leaks.
It’s entirely possible to put a pusher fan in front of the AC condenser but most would tell you it’s unnecessary, have you burped all the air out of the cooling system and did you install the proper 195* F thermostat?
 
It’s entirely possible to put a pusher fan in front of the AC condenser but most would tell you it’s unnecessary, have you burped all the air out of the cooling system and did you install the proper 195* F thermostat?
I have used a bleed funnel on it but I'm not sure if there is any air in there. Is there a way I can install an air bleed valve at the highest point in the system or something?

I used the correct thermostat. I do however have a high flow thermostat which I am considering installing. It never gets cold here so warming up engine is not a problem.
 
I have used a bleed funnel on it but I'm not sure if there is any air in there. Is there a way I can install an air bleed valve at the highest point in the system or something?

I used the correct thermostat. I do however have a high flow thermostat which I am considering installing. It never gets cold here so warming up engine is not a problem.
Moving water faster through the rad doesn’t allow it to cool as much and actually works the other way. I swapped a lower hose once and went through a month long (mine is not a daily driver) phase of overheating till all the air had purged itself.
 
FWIW, my old Mercedes has that kind of setup. The electric pusher is tied to certain conditions in the A/C and cooling system both.
 
Moving water faster through the rad doesn’t allow it to cool as much and actually works the other way. I swapped a lower hose once and went through a month long (mine is not a daily driver) phase of overheating till all the air had purged itself.
Maybe I should take it to my local radiator shop and get them to do a bleed or whatever they use... vaccum? not sure.
In summer, I get a boil over on super hot days as soon as I stop the car. I have a new aftermarket aluminium radiator and I am suspicious about weather the cap is doing its thing.
What radiator are you running? An OEM Mopar radiator should be able to cool even at those temps. Also, have you replaced your fan clutch?
New fan clutch yes. I've got a FloCool aftermarket radiator aluminium. I should have bought a genuine one, maybe I will.
 
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FWIW, my old Mercedes has that kind of setup. The electric pusher is tied to certain conditions in the A/C and cooling system both.
Interesting. I assume also that a TJ without an AC condenser would run cooler.Also a thermo fan in front would restrict air flow while driving... AHHH!
Can't wait for an electric version of a wrangler, internal combustion engines are just ridiculously complicated.
 
A fan in front wont restrict air in any meaningful way. It might help when things are really hot. Mercedes in general doesn't do stupid engineering and builds vehicles to perform in all conditions so I wouldn't expect any issues using that idea. However, your radiator is probably the problem. I'd also be sure your fan shroud is intact and replace your radiator cap if you haven't very recently. You can get fan clutches that engage earlier. They howl like crazy and suck power but might help as well.
 
Maybe I should take it to my local radiator shop and get them to do a bleed or whatever they use... vaccum? not sure.
In summer, I get a boil over on super hot days as soon as I stop the car. I have a new aftermarket aluminium radiator and I am suspicious about weather the cap is doing its thing.

New fan clutch yes. I've got a FloCool aftermarket radiator aluminium. I should have bought a genuine one, maybe I will.
Check the rad cap pressure. It should be 18psi/1.24 .
 
What radiator are you running? An OEM Mopar radiator should be able to cool even at those temps. Also, have you replaced your fan clutch?
X2, your cooling system won't overheat if you're running a Mopar radiator and water pump with a good fan clutch, 18 lb. radiator cap, and 195 degree non-failsafe thermostat. 110 is not unusual here in our California deserts and it routinely gets hotter than that. The world's hottest temperature ever recorded, 134 degrees, was in Death Valley which is only 250 miles from me. Jeeps with the factory cooling system have no problems in our SoCal deserts.

Aftermarket radiators RARELY work as well as the Mopar which truly has an outstanding design. So far, no one has found a radiator that works as well at cooling as the Mopar for less $$$ or even the same $$$. Nope adding more rows like going to a 2, 3, or 4 row radiator doesn't help. More rows does not equate to better cooling.