Gary Lewis Posted February 7 Author Share Posted February 7 Depends on the clutch. Many of the ones I've worked with have a fair bit of backdrag. And the ones that were looser had bad bearings (or were otherwise junk). Also, a lot of the E-fan reasoning/goals are reductions in rotating mass, which they indisputably are, especially in racing situations, especially drag. ---- I did an e-fan conversion (single speed + PWM controller) on my ranger and gained 1MPG on the highway. But, in that case, Ford already made a drop in alternator upgrade (3G 95A to 130A) so it was mostly an addition than a swap. On my F150, an e-clutch might make sense if the current draw wasn't too terrible, as it still has the stock 60A 1G setup; while I did add a CB radio (which is stock and doesn't draw much), I likely freed some capacity when I added LED headlights. But, due to the generally lower RPMs my F150 runs and the "on-off" nature of such a fan clutch, I doubt the gains would be as nice. And the price tag makes the deal that much sourer. Edit- the OP listing shows the fan as being variable... but the Hayden documentation Gary posted later makes it sound more like an on-off. Depending on how the unit's built, "variable" could mean partially slipping the clutch ... or just pulsing the clutch (similar to how A/C clutches work in practice). Either way, nowhere near as variable as a PWM E-Fan like I'm running on my Ranger. What I've read talks about duty cycle and PWM, so apparently they are pulsing the clutch to achieve variable speeds. So, Larry, you've already done it on the Ranger. What was the cost there? Did you use over-the-counter parts? And you said "PWM controller" and "single speed". Were the pulses many seconds long? Link to comment Share on other sites More sharing options...
ratdude747 Posted February 7 Share Posted February 7 What I've read talks about duty cycle and PWM, so apparently they are pulsing the clutch to achieve variable speeds. So, Larry, you've already done it on the Ranger. What was the cost there? Did you use over-the-counter parts? And you said "PWM controller" and "single speed". Were the pulses many seconds long? I used a single-speed fan & pigtail (used) from a 2011 Dodge Journey, which I trimmed and JB-welded into a mostly stock fan shroud. Idea being that if the motor fails, the OE fan (and many aftermarkets) can be detached from the plastic frame, allowing the motor to be replaced in this setup. The controller used is a Derale PWM controller: https://derale.com/product-footer/electric-fans/fan-controllers/pwm-controller/16797-detail (mine is a different discontinued model, but a very similar product). Single speed in that it's not a multi-tap fan (unlike the commonly swapped Volvo and Taurus 2-speed fans that are controlled by relays and a 2-stage thermal switch)... but infinitely variable in that the controller is using "true" PWM (high enough frequency that the motor "sees" it as analog). Fan control speed is based on a temp sensor on the cold-side radiator tank (super glued on) and a feed from the A/C control circuit (before the A/C pressure switches, so always on when HVAC is set to A/C or Defrost). Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 7 Share Posted February 7 I used a single-speed fan & pigtail (used) from a 2011 Dodge Journey, which I trimmed and JB-welded into a mostly stock fan shroud. Idea being that if the motor fails, the OE fan (and many aftermarkets) can be detached from the plastic frame, allowing the motor to be replaced in this setup. The controller used is a Derale PWM controller: https://derale.com/product-footer/electric-fans/fan-controllers/pwm-controller/16797-detail (mine is a different discontinued model, but a very similar product). Single speed in that it's not a multi-tap fan (unlike the commonly swapped Volvo and Taurus 2-speed fans that are controlled by relays and a 2-stage thermal switch)... but infinitely variable in that the controller is using "true" PWM (high enough frequency that the motor "sees" it as analog). Fan control speed is based on a temp sensor on the cold-side radiator tank (super glued on) and a feed from the A/C control circuit (before the A/C pressure switches, so always on when HVAC is set to A/C or Defrost). That's an 'interesting approach ' Larry! :nabble_smiley_good: Make do. Reduce, reuse... Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 7 Author Share Posted February 7 I used a single-speed fan & pigtail (used) from a 2011 Dodge Journey, which I trimmed and JB-welded into a mostly stock fan shroud. Idea being that if the motor fails, the OE fan (and many aftermarkets) can be detached from the plastic frame, allowing the motor to be replaced in this setup. The controller used is a Derale PWM controller: https://derale.com/product-footer/electric-fans/fan-controllers/pwm-controller/16797-detail (mine is a different discontinued model, but a very similar product). Single speed in that it's not a multi-tap fan (unlike the commonly swapped Volvo and Taurus 2-speed fans that are controlled by relays and a 2-stage thermal switch)... but infinitely variable in that the controller is using "true" PWM (high enough frequency that the motor "sees" it as analog). Fan control speed is based on a temp sensor on the cold-side radiator tank (super glued on) and a feed from the A/C control circuit (before the A/C pressure switches, so always on when HVAC is set to A/C or Defrost). Ok, I think I misunderstood. You used an electric fan, not an electro-viscous fan clutch. Right? Obviously that works, but then you are giving up energy on the conversion from mechanical to electrical and vice versa. The electro-viscous clutch approach doesn't have that loss. The study I linked to earlier shows a significant energy savings by going to electro-viscous over mechanical-viscous, and part of their findings show that the electro-viscous gives much better temp control because it is sensing coolant temp rather than air temp. I'd think the electric fan would have basically the same temp control as it is based on essentially the same controller approach. It just has the conversion losses. Link to comment Share on other sites More sharing options...
ratdude747 Posted February 7 Share Posted February 7 Ok, I think I misunderstood. You used an electric fan, not an electro-viscous fan clutch. Right? Obviously that works, but then you are giving up energy on the conversion from mechanical to electrical and vice versa. The electro-viscous clutch approach doesn't have that loss. The study I linked to earlier shows a significant energy savings by going to electro-viscous over mechanical-viscous, and part of their findings show that the electro-viscous gives much better temp control because it is sensing coolant temp rather than air temp. I'd think the electric fan would have basically the same temp control as it is based on essentially the same controller approach. It just has the conversion losses. Yes. Not an e-clutch... I thought I made that clear. Sorry! I'm sure there is some energy loss... but the e-fan can be controlled a lot more efficiently... and due to reduced fan mass and tighter tolerances with the duct around the fan, likely moves air more efficiently than the old clutch fan could. Keep in mind that the clutch does consume power to modulate the fan speed... so there' still a loss there. I don't know how much that is, but it's something. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 7 Share Posted February 7 Ok, I think I misunderstood. You used an electric fan, not an electro-viscous fan clutch. Right? Obviously that works, but then you are giving up energy on the conversion from mechanical to electrical and vice versa. The electro-viscous clutch approach doesn't have that loss. The study I linked to earlier shows a significant energy savings by going to electro-viscous over mechanical-viscous, and part of their findings show that the electro-viscous gives much better temp control because it is sensing coolant temp rather than air temp. I'd think the electric fan would have basically the same temp control as it is based on essentially the same controller approach. It just has the conversion losses. No it doesn't. You still use the mechanical energy to turn the fan AND you use electricity to lock it up (plus all the conversion losses, and the minute amount for the "smarts" behind it. How much power does it take to turn the fan? It takes -at minimum- that much to couple the fan to the shaft... on top of that. Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 12 Share Posted February 12 Gary, I don't know if you ever measured the space between the water pump shaft and radiator. I believe I measured it at 7" on Darth. I was looking into using a Crown Victoria fan (big electric one) but the fan shroud was a perfect fit, except the fan motor and water pump shaft needed to occupy the same space. I ended up with a T-bird unit, same motor, almost identical fan, but narrower. Using it I would make a blanking plate on the right side with rubber flap valves to blow open at highway speeds. You have to remember, Ford never intended to use the 460 in these trucks, the engineers figured the 400 would suffice. If some work had been done to the 400, like a better cam, 4 barrel etc. it might have worked. My fan controls would be in the EEC-V with a 200° or AC on low fan and a 220° high fan. These fans use an 80 amp relay for high and really move some air. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 12 Share Posted February 12 Gary, I don't know if you ever measured the space between the water pump shaft and radiator. I believe I measured it at 7" on Darth. I was looking into using a Crown Victoria fan (big electric one) but the fan shroud was a perfect fit, except the fan motor and water pump shaft needed to occupy the same space. I ended up with a T-bird unit, same motor, almost identical fan, but narrower. Using it I would make a blanking plate on the right side with rubber flap valves to blow open at highway speeds. You have to remember, Ford never intended to use the 460 in these trucks, the engineers figured the 400 would suffice. If some work had been done to the 400, like a better cam, 4 barrel etc. it might have worked. My fan controls would be in the EEC-V with a 200° or AC on low fan and a 220° high fan. These fans use an 80 amp relay for high and really move some air. It's almost like they added a JDAM kit and dropped it in from 20k'. Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 12 Author Share Posted February 12 Gary, I don't know if you ever measured the space between the water pump shaft and radiator. I believe I measured it at 7" on Darth. I was looking into using a Crown Victoria fan (big electric one) but the fan shroud was a perfect fit, except the fan motor and water pump shaft needed to occupy the same space. I ended up with a T-bird unit, same motor, almost identical fan, but narrower. Using it I would make a blanking plate on the right side with rubber flap valves to blow open at highway speeds. You have to remember, Ford never intended to use the 460 in these trucks, the engineers figured the 400 would suffice. If some work had been done to the 400, like a better cam, 4 barrel etc. it might have worked. My fan controls would be in the EEC-V with a 200° or AC on low fan and a 220° high fan. These fans use an 80 amp relay for high and really move some air. Jim - It think it would "only" take 20 ft with the heft of that 460. Bill - I agree that the longer-stroked 400 would probably have done the job if they'd put a bit of work into it. Like you said, a cam and a 4bbl would have made a huge difference, especially if they'd put a straight-up timing set in it. (I know you are going to tell us about their cheating and its consequences, so I set you up for that. ) As for the clearance on the radiator, I can't easily measure it the way you did but I do measure 2" between the front of the fan and the rear of the 4-core radiator on Big Blue. So if someone found an electro-viscous fan clutch that is less than 1" thicker than the mechanical-viscous clutches we are using then we could see if we could figure out how to adapt it. And have the EEC-V ECU's control it. You can sorta see that 2" clearance here: Link to comment Share on other sites More sharing options...
Nothing Special Posted February 12 Share Posted February 12 .... How much power does it take to turn the fan? It takes -at minimum- that much to couple the fan to the shaft... on top of that. I don't know about electro-viscous clutches, or if you were talking specifically about that type of clutch or if you were talking more generally. But more generally, the power required to clutch in a load is usually much lower than the power to actually turn the load. It's still an adder to the whole system. As you say, turning a fan takes the power to turn the fan regardless of how (or whether) you clutch it. And if it's a clutch that requires power to operate you have to add that power requirement to the system (and the systemic losses to generate that electric power in the mechanical alternator). But that clutching power isn't necessarily that high. Take the clutch between an engine and a manual transmission. The spring in that clutch doesn't need to be all that strong to transmit the torque of the engine. It's still small enough that you can compress it with your leg, and there's no way your leg can do what the engine is doing. And the wrap-spring clutches that my company makes take a flat amount of power to energize no matter what load they are being asked to transmit. Again, I don't know electro-viscous clutches. I imagine that (unlike wrap-spring clutches) they do require more power to transmit more power. But they probably don't require as much power to operate as they are transmitting. It's an adder, but not a (more than) doubler of the required power. Link to comment Share on other sites More sharing options...
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