Need advice regarding electric fan setup for 81 Scrambler with 4.2

[chrisdev01]

Hello everyone,

I purchased a 1981 CJ-8 Scrambler in January and have been slowly working through a number of corrections and maintenance items on the front of the engine. The previous owner had several incorrect or broken brackets installed, so I decided to go through the front of the engine and put everything back together properly.

So far the following work has been completed:

• Timing cover replaced and properly installed
• Harmonic balancer installed
• Crank pulley installed
• Correct alternator bracket installed
• Alternator installed
• Power steering bracket replaced (previous bracket was broken and missing the reinforcement plate)
• Incorrect California CCW Water pump replaced with correct CW pump
• Thermostat and thermostat housing installed
• Heater hoses replaced
• Accessory belts installed
• All battery cables replaced and grounds cleaned

While doing this work I also installed a new aluminum radiator, which is noticeably thicker than the OEM unit.

Because of the increased radiator thickness and reduced clearance to the water pump and pulleys, I am considering switching to an electric cooling fan rather than reinstalling the stock mechanical fan and clutch.

I would be very interested to hear from other CJ-8 Scrambler owners running the AMC 258 who have successfully installed an electric fan.

Specifically:

• What fan or kit did you use?
• Did you fabricate a shroud or use a kit with an integrated shroud?
• Any clearance issues with the water pump pulley?
• How has cooling performance been at idle or in traffic?

Photos of your setup would be especially helpful.

Thanks in advance for any guidance.

 

[bigwalton]

I have a 4.0 in mine and went electric after the mechanical fan that I thought had enough clearance nicked the radiator on a climb. So not a 258, but went there for the same reason.

I went with a single fan setup that died on the trail in Moab on me, much sooner than I thought a new fan should crap out.

Then I went to the the Ford Contour dual fan setup. I got a new Dorman (I think) replacement off Amazon. I butched up a clamping mount arrangement and the fit is about perfect with the built-in shroud.

They move a metric $%&# ton of air and with my stroker swap/Terminator X ECU I have a plan to go to variable frequency control of each fan separately because with the aluminum radiator I have and the amount of air they pull, ON/OFF operation cools things down so fast I can watch the temp drop on the gauge, then they cut off until they fire off again.

They're loud just because of the amount of air they pulll, literally you hear the wind. But if you want something that works, these certainly seem to do the trick really well. I personally think they need a variable frequency controller or a dual-trigger on two temp switches to run one alone until the other is needed. I never went that way because I really wanted to go straight to variable frequency.

 

[bigwalton]

I think I did a thread on here on the install...

 

[gr8dain]

I previously had a problem similar to yours and bumped the radiator causing it to leak. I went with the Dorman set up for the ford contour as Eric mentioned. It worked fine but I was going through 40 amp fuses faster than I wanted. When I swapped to a 4.0, i went back to a mechanical fan. But I opted not to have the clutch and used a small spacer with the non clutch fan. I also slid the aluminum radiator into the opening of the grill through the bottom of the grill. That alone gave me a good but of clearance. I have a thread about my motor swap that should have pics. Let me try to find one to put here.