THREE 10" PUSHERS WILL KEEP IT COOL, FULL DETAILS!

[BARILLMS]

My Jeep was running hot, and I initially went the "Taurus" fan route.

Electric fans are great except for a few problems I encountered.

I've exhausted the cooling fan options to the very end, and this is BY FAR

the best solution there is out there.

 

The problem with the XJ radiator, is the shape. It's NOT a square like some truck radiators... or CJ or YJ radiators. SO, you plop a 14" or 16" fan behind the radiator pulling air, it's a waste!!! It's doesn't fit, the fan hangs down below the radiator and isn't doing what's you're intending it to do.

don't BOTHER WITH A BIG FAN, or TAURUS FAN in an XJ or MJ.

 

Electric Fans have built-in thermal shut off points. Your engine is hot, on a 90 degree day in August, the engine compartment is like an oven.... just holding all the heat in there. Sure, you can vent the hood (I did) but it's still hot in there. Having "PULLERS" behind the radiator isn't good, because when the engine gets hot... the fans will SHUT OFF, then you're done. Now you have nothing.

 

#1 the fans must fit the radiator. 10" fans are THE ONLY fans that will fit our radiators and move air through it efficiently. REVERIBLE "S BLADE" FANS MUST BE USED. They are $25 each on ebay.

#2 putting fans in FRONT of the radiator, away from the hot engine is the BEST IDEA because they won't get hot and quick working.

#3 THREE CHEAP 10" electric fans from Ebay fit inside the XJ grille area

PERFECTLY across the front.

#4 They MUST be very sturdily mounted onto a sheet of 1/4" plastic,

while not warping or bending the fan shroud causing the blades to rub.

 

Here's how to do it:

[jtdesigns]

Cool,,,lol oun intended... so whats the story with the plastic again????

[Belto]

wait,, this is to pull hot air out or to push colder air to the radiator?? won't the plastic be a restriction to the air to the radiator? sorry if I ask to much its to the get the facts right...

[jtdesigns]

wait,, this is to pull hot air out or to push colder air to the radiator?? won't the plastic be a restriction to the air to the radiator? sorry if I ask to much its to the get the facts right...

It pushes air in, the shroud (plastic) make it where the fans do push air, instead of just spinning, ie makes the fan more efficient.

[Belto]

oo okok got it thanx

[xjcrazy09]

interesting write up. Could be something to look into doing

[HOrnbrod]

My Jeep was running hot, and I initially went the "Taurus" fan route.

Electric fans are great except for a few problems I encountered.

I've exhausted the cooling fan options to the very end, and this is BY FAR

the best solution there is out there.

 

The problem with the XJ radiator, is the shape. It's NOT a square like some truck radiators... or CJ or YJ radiators. SO, you plop a 14" or 16" fan behind the radiator pulling air, it's a waste!!! It's doesn't fit, the fan hangs down below the radiator and isn't doing what's you're intending it to do. don't BOTHER WITH A BIG FAN, or TAURUS FAN in an XJ or MJ.

 

Electric Fans have built-in thermal shut off points. Your engine is hot, on a 90 degree day in August, the engine compartment is like an oven.... just holding all the heat in there. Sure, you can vent the hood (I did) but it's still hot in there. Having "PULLERS" behind the radiator isn't good, because when the engine gets hot... the fans will SHUT OFF, then you're done. Now you have nothing.

 

#1 the fans must fit the radiator. 10" fans are THE ONLY fans that will fit our radiators and move air through it efficiently. REVERIBLE "S BLADE" FANS MUST BE USED. They are $25 each on ebay.

#2 putting fans in FRONT of the radiator, away from the hot engine is the BEST IDEA because they won't get hot and quick working.

#3 THREE CHEAP 10" electric fans from Ebay fit inside the XJ grille area

PERFECTLY across the front.

#4 They MUST be very sturdily mounted onto a sheet of 1/4" plastic,

while not warping or bending the fan shroud causing the blades to rub.

 

Here's how to do it:

 

I completely disagree with about everything you stated.

 

1. First, the original mechanical fan (15") and the aux electric fan (12") are pullers. They are pullers to allow max airflow w/o restriction through the radiator. Your fans in front of the radiator restrict airflow when moving. 75%-80% of the effective cooling is by airflow when moving; you get into trouble sitting in standstill traffic and the airflow stops. The puller fans would need to be running constantly to make up for the restricted airflow they cause.

 

2. A 14" electric fan fits perfectly in the existing mechanical fan shroud, and depending on its CFM, it moves as much if not more air than the clutch fan. None of the fan hangs down below the shroud; it's an inch less in diameter than the mechanical fan in the same shroud! I run a 14" on a Spal controller set to turn on the fan at 50% at 190* and 100% at 205*. For backup if needed I have wired in a dash bypass switch on the existing aux fan because the factory aux fan temp setting (218*) is to high IMNSHO. Had to use it once when the temp crept a bit over 210* after 40 minutes stuck in traffic. With both fans running, the temp drops like a stone.

 

3. Neither of my fans have "built-in thermal shut off points". No decent automotive electric fans have thermal switches. If an automotive cooling fan shuts off because of engine compartment temps, there's something wrong with it.

 

4. You never mentioned the amp draw per fan, but obviously you are not running a variable speed controller, so they're either off or running at 100%. If you haven't upgraded your electrical system (larger alternator, larger mains cables, etc.) let us know when your alternator fries or a wire fire starts.

 

5. REVERIBLE "S BLADE" FANS MUST BE USED. Why? :nuts: It's not the shape of the blades that matter, it's the rated CFM of the fan. I don't give a rats butt if the blades are W shaped, as long as it moves all the air I want it to.

 

6. The XJ/MJ radiators are not square. That's the only thing you said I agree with. :D

 

7. WHY DO YOU SHOUT SO MUCH??

 

The key to effective cooling is keeping the entire cooling system in first class shape to keep the coolant flowing as designed - period. A clean single or dual core radiator (I don't think the 3-core rads flow as well), a good flowing water pump, proper mix of antifreeze and water, an unrestricted exhaust system (i.e. clogged cat :eek: ), proper coolant level, rad caps and overflow bottles in good operating condition, and/or trapped air in the system. If the cooling system is in good shape, and you're moving at +30 or so, we wouldn't even need fans. But unfortunately that's not always the case.

[mudhound0530]

No decent automotive electric fans have thermal switches

 

x2

[XJs4Ever]

These stock systems worked at some time, right? Otherwise every potential buyer would end up stranded on the test drive. My 89 XJ worked fine until one day POOF it overheated from then on. I like the 3-fan idea but ditto on the current draw and the fans I have installed - be they pushers or pullers - I just reversed polarity to spin them which ever way I wanted.

 

My 89 MJ overheats constantly and I have yet to find a solution short of a 3 row rad. The prior owner also had problems cuz it has a new single row rad and it is an open system. Seems to me that the problem [or one of the problems] is these stupid shaped rads can't move the coolant thru fast enuf. Anyone ever put a smaller pulley on the pump?

 

I just put a 195 thermo in cuz it had a 180 but thats cuz the heater wasn't working well, but now I think theres a problem with the box or core. Also cuz I welded my fan to the clutch [constant 1-1 ratio rather than variable] which probably made the most improvement in cooling than anything, to the point of running too cool - thus the thermo swap.