Fan clutch upgrade...

[franklin2]

Why wouldn't either one of these PWM controllers from Amazon work?

This one is rated for 5 amp output

https://www.amazon.com/uniquegoods-...195327&sr=8-3&keywords=12+volt+pwm+controller

This one is rated for 60 amps

https://www.amazon.com/ELEGIANT-10-...195327&sr=8-4&keywords=12+volt+pwm+controller

Once you hooked it up and verified it was working, you could set the speed for different conditions with the speed control manually, and then measure the resistance for that speed. You could have say 3 speeds. So instead of the potentiometer, you would have 3 resistors with small 12v relays which could be fired by temperature switches and the A/C clutch system.

 

[laserjock]

I wouldn’t recommend a controller like that if your going to put a nice fancy controllable fan clutch on then drive it with an on/off controller.

As laserjock said, these clutches use PWM to drive the clutch, there’s ignition controlled 12v sent to the clutch and the controller supplies the duty cycle to ground for how much lockup you want. The clutch also has a built in tach sensor that can be used for monitoring or part of the feedback control of the controller if you wanted.

So far it’s looking like a custom made controller is going to have to be built as I’m not finding any online that will do more then just on/off control, I’m going to try and build one that takes engine temp, ac pressure, trans temp and pre/post intercooler temp and control the fan probably in a step format as I don’t know how to intergrate PID control into a controller.

I have not done pwm directly coded in the micro controller but I have driven controllers with an analog output to a pwm board. That works pretty well but it’s an extra component. I could see setting up a calculation that accounts for all the things you mentioned to come up with a duty cycle. Just have to figure out what it would look like and play with weighting the terms. Shouldn’t be too hard at all really. Could monitor the tach sensor but you really don’t need it once you know at what duty cycle the fan is essentially locked. It’s probably something short of 100 %. Then work your scale backward from there. You don’t really need pid because there really doesn’t need to be a set point.

 

[lotzagoodstuff]

Very nice write up, seems like a no brainer once you get the controller sorted out.

Anybody have any experience with the Delta controller? I think they have a PWM model that might make this pretty easy.

Cool technology to one of the few remaining weak points of the IDI in that the stock fan clutch is better described as the "suck fan clutch".

Staying tuned

 

[franklin2]

Very nice write up, seems like a no brainer once you get the controller sorted out.

Anybody have any experience with the Delta controller? I think they have a PWM model that might make this pretty easy.

Cool technology to one of the few remaining weak points of the IDI in that the stock fan clutch is better described as the "suck fan clutch".

Staying tuned

This whole project is down the drain if he can't figure out a thread adapter. I see a potential for someone to make some money if they wanted to start making an adapter. There has to be something better than the original unit that comes on at 230 degrees. If this pans out I could get rid of my locked fan.

P.S. How hard are the original clutches to take apart? Could you take it apart, and be left with a shaft and the original threaded nut. Chuck that in the lathe and turn the hex of the original nut down till it was round. Is there enough meat left to turn the metric threads onto the remaining old nut?

 

[franklin2]

Does anyone know what size wrench takes the original clutch off? He said the new clutch had 40mm threads, which comes out to 1.575 inches.

 

[crash-harris]

Isn't the whole point of having an electric fan that it's off and not creating any resistance for the engine when it's not needed? Otherwise, I seem to remember a mod on here awhile ago about getting the stock clutch to engage at a lower temperature.

 

[no mufflers]

you can mess with the spring i guess. i added oil to mine and it works really well but its always engaged and it doesn't need to be most of the time.

 

[centennial60]

Does anyone know what diameter the 6.0 fans are?

 

[DrCharles]

Does anyone know what size wrench takes the original clutch off?

It's 1-7/8" on mine.

 

[david85]

Is there any way that electronic actuator could be adapted to the older style fan clutch? That could simplify things, maybe?

 

[ifrythings]

Why wouldn't either one of these PWM controllers from Amazon work?

This one is rated for 5 amp output

https://www.amazon.com/uniquegoods-...195327&sr=8-3&keywords=12+volt+pwm+controller

This one is rated for 60 amps

https://www.amazon.com/ELEGIANT-10-...195327&sr=8-4&keywords=12+volt+pwm+controller

Once you hooked it up and verified it was working, you could set the speed for different conditions with the speed control manually, and then measure the resistance for that speed. You could have say 3 speeds. So instead of the potentiometer, you would have 3 resistors with small 12v relays which could be fired by temperature switches and the A/C clutch system.

Those both use a potentiometer to control fan speed and have no way to control fan speed based on temperature, you could use it if you want a completely manual system but I would like something more on the adjustable automatic side.

This whole project is down the drain if he can't figure out a thread adapter. I see a potential for someone to make some money if they wanted to start making an adapter. There has to be something better than the original unit that comes on at 230 degrees. If this pans out I could get rid of my locked fan.

P.S. How hard are the original clutches to take apart? Could you take it apart, and be left with a shaft and the original threaded nut. Chuck that in the lathe and turn the hex of the original nut down till it was round. Is there enough meat left to turn the metric threads onto the remaining old nut?

The bushing shouldn’t take a good machinists more then an hour to make, I have a small lathe I’m going to try and make one on but I’m not very experienced with making threads yet.

As for the original fan clutch, you could take it apart and mill down the 47/48mm hex to the 40mm x 2.0 thread and use that as a bushing but then your destroying a clutch you could sell.

Does anyone know what size wrench takes the original clutch off? He said the new clutch had 40mm threads, which comes out to 1.575 inches.

It’s a 47/48mm nut from what I recall, my idi fan clutch wrench says 47mm but measures 48.xxmm and it fits on the 6.4L fan nut.

Isn't the whole point of having an electric fan that it's off and not creating any resistance for the engine when it's not needed? Otherwise, I seem to remember a mod on here awhile ago about getting the stock clutch to engage at a lower temperature.

The problem with the factory clutch is it only reacts to engine temp and fairly late at that unless you modify it to turn on earlier which is just wasting engine power for nothing. With the electronic clutch you can engage it to help with ac performance at idle, tranny temp when off roading or climbing steep hills at a slow speed where the torque converter would be unlocked and pumping out large amounts of heat and even help your intercooler on the large steep hills where you have little air flow and large engine load.

Does anyone know what diameter the 6.0 fans are?

Not sure on the fan but the fan clutch mounting is the same between the 6.9/7.3idi, 7.3ps, 6.0ps, 6.4ps. The 6.9/7.3idi and 6.4ps are both standard rotation (left hand thread) and the 7.3ps, 6.0ps and 6.7ps are reverse rotation (right hand threads).

Here’s a few links on the specs of the different fan clutches

6.9/7.3 idi

https://www.rockauto.com/en/moreinfo.php?pk=1793468&cc=1126729&jsn=8

7.3ps

https://www.rockauto.com/en/moreinfo.php?pk=1793514&cc=1127090&jsn=10606

6.0ps

https://www.rockauto.com/en/moreinfo.php?pk=1793478&cc=1427891&jsn=10703

6.4ps

https://www.rockauto.com/en/moreinfo.php?pk=2420658&cc=1444017&jsn=10800

6.7ps

https://www.rockauto.com/en/moreinfo.php?pk=6367779&cc=1501968&jsn=10893

Is there any way that electronic actuator could be adapted to the older style fan clutch? That could simplify things, maybe?

No way of modifying the idi’s clutch cheapy or easily even if you could find the electronic lockup mechanism sold separately.

 

[crash-harris]

The problem with the factory clutch is it only reacts to engine temp and fairly late at that unless you modify it to turn on earlier which is just wasting engine power for nothing. With the electronic clutch you can engage it to help with ac performance at idle, tranny temp when off roading or climbing steep hills at a slow speed where the torque converter would be unlocked and pumping out large amounts of heat and even help your intercooler on the large steep hills where you have little air flow and large engine load.

That's the point I was getting at. Using a cheap little Hayden fan controller with a threaded temp probe (I don't trust external contact ones) would be a cheap, easy way to control the fan. Setting it to kick on a tad sooner is very easy and they shut off at a pre-determined temperature relative to where you set it to kick on. The only provision those units don't have is to account for engine load, but temp on/off and triggering when the A/C is triggered. For severe duty situations (traffic, long grades, off-road), that's where manual control comes into play. Really, the most difficult part of that equation is determining how much power it'll draw (particularly on startup) and finding constant-duty relays that can handle the load.

 

[ifrythings]

That's the point I was getting at. Using a cheap little Hayden fan controller with a threaded temp probe (I don't trust external contact ones) would be a cheap, easy way to control the fan. Setting it to kick on a tad sooner is very easy and they shut off at a pre-determined temperature relative to where you set it to kick on. The only provision those units don't have is to account for engine load, but temp on/off and triggering when the A/C is triggered. For severe duty situations (traffic, long grades, off-road), that's where manual control comes into play. Really, the most difficult part of that equation is determining how much power it'll draw (particularly on startup) and finding constant-duty relays that can handle the load.

I believe your referring to something like this?

https://www.rockauto.com/en/moreinfo.php?pk=3843708&cc=1444017&jsn=11

This will work for an on/off controller at some preset temperature, what I’m saying is I don’t want to run it at either 0% or 100%, I want the fan to turn on say 30% at 200F and 40% at 210F and 70% at 220F and at 230F be 100% on. Basically I want it to work how a computer can control its own cpu fan, low speed at low demand and increase speed as demand increases, keeping noise and power demand optimal.

Hopefully we aren’t saying the same thing just differently as I’ve been known to do that haha.

As for power requirements for the clutch fan, you would only need a few amps (maybe ~5) to drive it, this isn’t a big dc motor, it’s more like a solenoid for current requirements, I’ll try and bring the clutch home this weekend and hook it up the power supply and see just how much current it requires to turn on full.

 

[ifrythings]

Good point. Maybe mill 2 small slots opposite each other on the 40mm side so it could be removed with a simple piece of angle iron of the appropriate thickness cut to fit?

I was just thinking, how about just cutting one side of the bushing in half? That way it will still be strong thread wise and should unscrew from either part easily?

 

[chillman88]

I was just thinking, how about just cutting one side of the bushing in half? That way it will still be strong thread wise and should unscrew from either part easily?

I don't know, I kinda like OE style. I think you need to spend a few weeks designing it so it needs a special $80 tool that would be completely useless for anything else.

On second thought.... I like your idea better