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Discussion Starter · #1 ·
I'm in the process of putting together the pieces for my CPL 858 4BT, and I would like to use a serpentine fan for the radiator. Is there anything that would prohibit me from using a belt-driven fan?

Pantherman
 

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There is no good reason to have a belt driven one. I have my radiator completely blocked off, and my engine NEVER gets hot. I have an electric fan I can install, but I wonder if I will ever need it........ever.
 

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Discussion Starter · #3 ·
There is no good reason to have a belt driven one. I have my radiator completely blocked off, and my engine NEVER gets hot. I have an electric fan I can install, but I wonder if I will ever need it........ever.

I am covering all bases just to be sure.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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There are several options, cheapest is to add it directly to the, pulley. Second way is to use the Dodge option, pre 94 or later. Pre 94 put the fan centered up high or post 94 puts the fan lower and to the left, this also put the fan forward about a 1.5 inches. I'm using the post 94 Dodge fan setup. If you want to tow with your 4BT and run AC you should have a mechanial fan.
 

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Discussion Starter · #5 ·
There are several options, cheapest is to add it directly to the, pulley. Second way is to use the Dodge option, pre 94 or later. Pre 94 put the fan centered up high or post 94 puts the fan lower and to the left, this also put the fan forward about a 1.5 inches. I'm using the post 94 Dodge fan setup. If you want to tow with your 4BT and run AC you should have a mechanial fan.
What would I have to do to add it to the pulley directly? I would worry a little about balance at that point. I will not being doing any towing of any kind with this, this vehicle will be nothing more than a daily driver.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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I think there was a fan option for the 4B's used in medium duty trucks but I don't have a part number for you. Ask around.
 

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I took a fan from a Dodge PU with a small block. The bolt diamater is right but the mounting patern seems to be slightly smaller in diamater. The bolt holes seem to be just a hair off but the bolts do go in. The problem with my motor is that the shaft just protrudes from the pulley that the fan would be mounted to. The shaft is much larger in diamater than the one on the Dodge small block. That results in the fan hub not seating properly on the pulley. There needs to be a small spacer machined with the appropriate hole bored into it to mount the fan.
The next problem is the fan location. If you are running the P30 radiator hose the fan will hit it. If using the P30 setup the spacer will have to move the fan forward a few inches. If you are using a radiator with a drivers side inlet the radiator hose will not clear the fan either, unless you have one with a close bend. The motor water outlet is lower than the outside diamater of the fan.
I hate electric fans so I would really like to use a mechanical one. In this case it looks like the electric is the way to go. I have the electric unit that came from my doner truck. It's ugly but it will probably be used.
 

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I will not being doing any towing of any kind with this vehicle
Last night I pulled a '64 Chevy longbed 2WD (5,000 lbs? with scrap in back) on my 1400 lb trailer behind my 5800 lb truck. I figure over 13K-14K lbs total. Up and down lots of hills, outside air temp about 40* F, for about 70 miles.

No fan.

Only thing I needed for it to keep cool was to slice about 1" off of the cardboard piece completely blocking my radiator. 185* water temp the whole way.
These suckers run COOL!

I wouldn't bother installing a fan unless you found out later you need one.
 

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I need a fan for the A/C. The unit will kick out on high pressure without a fan.
 

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Couldn't you put 2 small fans in front of the evaporator blowing into the engine compartment? sound less complicated, and it is commonly used on smaller SUV's that i've seen. Then having to draw through the radiator wouldn't be a complication.
 

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Couldn't you put 2 small fans in front of the evaporator blowing into the engine compartment?
I had to do that with my 5.0 Ranger, there wasn't enough room behind the radiator for any fans.
 

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Is there room in front of the evaporator for fans? Of course, if the motor runs cool, you could go with a smaller radiator that an electric fan would be able to pull through. Think you have to have a pulley powered fan with a 3 core radiator, if i'm not mistaken. I'm thinking a 1 core radiator with electric fans mounted in the engine compartment should do the trick you want.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Which is the reason I want a fan, I will be running A/C and I like my A/C VERY cold.


Pantherman
I would second the fan(s) in front of the evaporator. I used to run electric fans for both the engine cooling and for the AC evaporator. The electric fan for the engine proved to be inadaquate here in Arizona even with out the AC, so I added the machinal engine fan, now it will bearly read above 185 F on the hotest condictions. I still use the AC pusher fan on the evaporator with the AC in town or wheeling, the engine doesn't get hot enough to trip the fan clutch to come on.
 

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I still use the AC pusher fan on the evaporator with the AC in town or wheeling, the engine doesn't get hot enough to trip the fan clutch to come on.
Good point.
 

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My '91 Chevy 4BTA came with a massive mechanical fan. I removed it in favor of an electric (sorry already sold). I'm sure there are plenty of them floating around from people who have done the same. Some people prefer mechanical fans and that is totally cool. It is powered and mounted to the pulley that looks like the water pump or where it would be on a regular vehicle (when in fact the water pump is the idler pulley to the left of it that is powered by the *back* of the serp belt). My 1990 4BT came with the dinkiest electric fan you have ever seen with no shroud, and also seldom kicked on... Hope it helps... Andre
 

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Discussion Starter · #18 ·
The temps during the summer here in upper Ohio regularly hit the mid 90's, usually the high 90's to low 100's, I've not yet seen a diesel or gas engine in this town survive a summer without a radiator fan.

Pantherman
 
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