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Electric vs mechanical fans?

gr8dain

Old and Slow
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Ok. So I wanted to not muddy up tge fan clearance thread. So I started a new one for my question.

I switched to the contour electric fan on my last 4.2 and it was OK, but had issues with the flex-a-lite control module I used and went through a few fuses causing me to overheat more than I would like to admit. So when I did my 4.0 swap, I went back to a mechanical fan set up. I used a clutch fan.

This weekend while beating it on the rocks, the fan ate my radiator like it did when I had my 4.2. So I am considering an electric fan set up again, or maybe a mechanical fan without a clutch.

So, if I do electric, should I go with a Dorman fan set up for the Contour again, to something else? What controller would you use?

If I go with a mechanical fan, any thoughts on one without a clutch?

Keep in mind that I have a second temp sensor added to my t-stat housing so the mechanical fan has to set out a little to clear it. See this pic.
IMG_6778.jpeg
 

83CJ-8

Trying to catch up
Silver Member
City
Lewes
State
DE
flex-a-lite control module I used and went through a few fuses causing me to overheat more than I would like to admit. What controller would you use?
On my Contour fan, the flex-a-shit controller never worked correctly. When I called them about the warranty I was told "Not covered, sorry about your luck. I wired in a switch and relay for manual on & off.

I will be swapping out to the https://www.dakotadigital.com/index...od/prd1207.htm] Dakota Digital Fan Controller at some point once I finish out my housing box
 
Last edited:

gr8dain

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On my Contour fan, the flex-a-shit controller never worked correctly. When I called them about the warranty I was told "Not covered, sorry about your luck. I wired in a switch and relay for manual on & off.

I will be swapping out to the https://www.dakotadigital.com/index...od/prd1207.htm] Dakota Digital Fan Controller at some point once I finish out my housing box

Interesting to hear I am not the only one who had a Flex a lite with bad results. I will check the one you linked. Thanks.
 

FLCJ8

Legacy Registered User
City
Palm Bay
State
FL
On my Contour fan, the flex-a-shit controller never worked correctly. When I called them about the warranty I was told "Not covered, sorry about your luck. I wired in a switch and relay for manual on & off.

I will be swapping out to the https://www.dakotadigital.com/index...od/prd1207.htm] Dakota Digital Fan Controller at some point once I finish out my housing box
Are you planning on wiring it up so it can be easily switched to manual mode if the controller takes a dump?
I had thought of doing that, it seems like yours would be very simple to do by substituting a double throw switch since you already have the manual system in place.
 

spankrjs

Scrambler Junkie
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Biloxi
State
MS
What was your face of clutch to face of radiator gap?
 

sdsupilot

CJ-8 Member
City
OKC
State
OK
Can you remove the second temp sensor and move the fan back away from the radiator? I am assuming it is for the EFI. You may be able to relocate it and/or have the computer send a temp signal to you gauge.

Back when I had an I6 I actually moved the engine back 1 set of holes in the transfer case skid plate. That helped with the clearance.

I am firmly in the mechanical clutch fan camp. It is a bit warmer in OK, but I have yet to see a rig with electric fans (aftermarket) not overheat here when wheeling in the summer. I've had friends run thermostat switches and relays that have failed. Fan motors have just quit. Even know folks that wired the electric fans to a switch and forgot to turn them on.
 

cjwoodman1

New member
City
Cheshire
State
CT
My flexalite controller burned up yesterday causing a boil over. I let the motor cool then got on the highway and never stopped moving the whole time while watching the temp gauge. I ordered a new controller and will be wiring a manual bypass switch in as well.
 

gr8dain

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What was your face of clutch to face of radiator gap?
I was at about an inch. Right now it is about the thickness of my finger, so less than an inch. I think the grill came back some.
 

gr8dain

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Can you remove the second temp sensor and move the fan back away from the radiator? I am assuming it is for the EFI. You may be able to relocate it and/or have the computer send a temp signal to you gauge.

Back when I had an I6 I actually moved the engine back 1 set of holes in the transfer case skid plate. That helped with the clearance.

I am firmly in the mechanical clutch fan camp. It is a bit warmer in OK, but I have yet to see a rig with electric fans (aftermarket) not overheat here when wheeling in the summer. I've had friends run thermostat switches and relays that have failed. Fan motors have just quit. Even know folks that wired the electric fans to a switch and forgot to turn them on.

The tapped hole with the second sensor is for the gauge as the stock location is being used for the computer. Maybe I could figure out a new way, but would rather leave that as is.
 

spankrjs

Scrambler Junkie
Lifetime Member
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City
Biloxi
State
MS
I was at about an inch. Right now it is about the thickness of my finger, so less than an inch. I think the grill came back some.
On my red Scrambler I think I have an inch. Running 4.0, CJ v-belt front accessories, NAPA clutch fan. I have the Hesco t-stat housing so coolant temp sender sticks out toward driver side.

I have beem using a Summit 2 core radiator, no issues. The three cores are too thick IMO for the clutch fan. I ran a 3 core with OEM non clutch fan previously, no issues. I don't beat on mine, but wheel it, so it gets used. You think the grill body mount failed? Even so, the fenders would hold the grill? Something definitely shifted?
 
Last edited:

spankrjs

Scrambler Junkie
Lifetime Member
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City
Biloxi
State
MS
1" to 1-1/4" clearance from face of clutch to face of radiator.

20230918_212734.jpg

Hesco t-stat housing. Sender facing front is for a secondary temperature gauge. Coolant temp sensor facing driver side.

Like @sdsupilot I am a firm believer in mechanical fans.

20230918_212747.jpg
 

STSFCTN

Active member
Silver Member
City
Centennial
State
CO
I used the dorman contour fan and the junkyard wires using this diagram. This Summer I just bypassed the engine coolant sensor with a paperclip to keep it on high continuously. There are a few writeups online using a Volvo temp sensor for the high and low function of these fans.
 

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Grantshire

Legacy Registered User
Member
City
Richmond
State
VA
Ok. So I wanted to not muddy up tge fan clearance thread. So I started a new one for my question.

I switched to the contour electric fan on my last 4.2 and it was OK, but had issues with the flex-a-lite control module I used and went through a few fuses causing me to overheat more than I would like to admit. So when I did my 4.0 swap, I went back to a mechanical fan set up. I used a clutch fan.

This weekend while beating it on the rocks, the fan ate my radiator like it did when I had my 4.2. So I am considering an electric fan set up again, or maybe a mechanical fan without a clutch.

So, if I do electric, should I go with a Dorman fan set up for the Contour again, to something else? What controller would you use?

If I go with a mechanical fan, any thoughts on one without a clutch?

Keep in mind that I have a second temp sensor added to my t-stat housing so the mechanical fan has to set out a little to clear it. See this pic.
View attachment 110866
Fought overheating issues for a couple years and finally stepped up to a Sp
Ok. So I wanted to not muddy up tge fan clearance thread. So I started a new one for my question.

I switched to the contour electric fan on my last 4.2 and it was OK, but had issues with the flex-a-lite control module I used and went through a few fuses causing me to overheat more than I would like to admit. So when I did my 4.0 swap, I went back to a mechanical fan set up. I used a clutch fan.

This weekend while beating it on the rocks, the fan ate my radiator like it did when I had my 4.2. So I am considering an electric fan set up again, or maybe a mechanical fan without a clutch.

So, if I do electric, should I go with a Dorman fan set up for the Contour again, to something else? What controller would you use?

If I go with a mechanical fan, any thoughts on one without a clutch?

Keep in mind that I have a second temp sensor added to my t-stat housing so the mechanical fan has to set out a little to clear it. See this pic.
View attachment 110866
Fought overheat
Ok. So I wanted to not muddy up tge fan clearance thread. So I started a new one for my question.

I switched to the contour electric fan on my last 4.2 and it was OK, but had issues with the flex-a-lite control module I used and went through a few fuses causing me to overheat more than I would like to admit. So when I did my 4.0 swap, I went back to a mechanical fan set up. I used a clutch fan.

This weekend while beating it on the rocks, the fan ate my radiator like it did when I had my 4.2. So I am considering an electric fan set up again, or maybe a mechanical fan without a clutch.

So, if I do electric, should I go with a Dorman fan set up for the Contour again, to something else? What controller would you use?

If I go with a mechanical fan, any thoughts on one without a clutch?

Keep in mind that I have a second temp sensor added to my t-stat housing so the mechanical fan has to set out a little to clear it. See this pic.
View attachment 110866
Fought overheating for two years on my trail rig with the tricked out 4.3 and super big stainless headers. 3,000 cfm electric puller just couldn’t do it. Did a bunch of stuff that didn’t work and finally tried a Spal electric fan. Wow! The Spal is fantastic, problem solved! I will never use anything else!
 

gr8dain

Old and Slow
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Ashburn
State
VA
On my red Scrambler I think I have an inch. Running 4.0, CJ v-belt front accessories, NAPA clutch fan. I have the Hesco t-stat housing so coolant temp sender sticks out toward driver side.

I have beem using a Summit 2 core radiator, no issues. The three cores are too thick IMO for the clutch fan. I ran a 3 core with OEM non clutch fan previously, no issues. I don't beat on mine, but wheel it, so it gets used. You think the grill body mount failed? Even so, the fenders would hold the grill? Something definitely shifted?

Stuff definitely shifted. The grill is rotated slightly counter clockwise when looking at it head on. The pass side fender is lower in the front and pulling from the tub.

I am leaning toward a mechanical fan but without the clutch. Right now, the distance between the clutch and the radiator is almost nothing. I have two temp sensors on the t-stat housing. The stock one and one for the temp gauge that you can see sticking out toward the grill. I will start disassembling later this week (Friday or Sat). I will loosen things up and see what play I have before I actually remove the grill and start to remove the radiator, etc.

IMG_6815.jpeg
 

Belizeit

CJ-8 Member
Gold Member
City
River Ridge
State
La
This last picture you posted we can see the bottom of the radiator where the frame or bottom tank meets up with the fins. On the radiator that Raymond mentioned from Summit, The fins actually sit back in probably a half inch more and that probably would give you more room.
 

gr8dain

Old and Slow
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Ashburn
State
VA
I just ordered a new radiator and a new shroud. Still looking for the fan parts, but by buying the shroud, I made the decision to go mechanical. Just without the clutch. I am going to start the disassembly this weekend.
 

spankrjs

Scrambler Junkie
Lifetime Member
SOA Member
City
Biloxi
State
MS
The shrouds are different between the clutch fan and the non clutch fan, just FYI. :thumbsup:
 
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