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Electric fan [message #354147] Sun, 26 April 2020 13:11 Go to next message
thigh19 is currently offline  thigh19   United States
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I drive truck for a living and on a semi, when the clutch fan kicks on, you can feel it in the power. Wondering if the clutch fan you guys are using, does the same? Why not just electric, and if electric, push or pull? Seems like push is the obvious,for space sake, but looking for recommendations.
Re: Electric fan [message #354149 is a reply to message #354147] Sun, 26 April 2020 13:43 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Thom,

(Me again) Wink

Several have tried electric fans, but I have heard of few that were truly successful. If you go that way be sure to upgrade to a 100 Amp alternator. You can get more, but then the case changes and that make is unsimple.

When I still had the iron fan and a typical clutch, I could both feel and hear it when the fan came on. With the electric clutched fan kit, I can still hear and feel it, but as bad as my hearing is I have to pay attention to hear it and feel it in engine power is almost not there.

At this time, I have three mods that I recommend for all the early coaches, reaction arms for rear brakes with no other changes, Pertronix 1181LS to replace the points, and the electric fan clutch set. The first I class as a safety essential, the second is a Major Convenience and the last is just really nice because it is quieter and you won't have to replace a fan clutch on the road (again).

My fan installation is a Mark 1 mod 0 and I am still working on a better control system. After I got it installed, #7 piston shed some rings and about the time I got that squared away, we broke a lower control arm 900+ miles from home (still working on the repairs from that). This season I am going to work on that when I can. Other people here may have good ideas.

Matt


thigh19 wrote on Sun, 26 April 2020 14:11
I drive truck for a living and on a semi, when the clutch fan kicks on, you can feel it in the power. Wondering if the clutch fan you guys are using, does the same? Why not just electric, and if electric, push or pull? Seems like push is the obvious,for space sake, but looking for recommendations.


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Electric fan [message #354150 is a reply to message #354147] Sun, 26 April 2020 13:48 Go to previous messageGo to next message
Hal StClair   United States
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Location: Rio Rancho NM
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It's been tried but with little success. It should be possible for certain but will take some engineering. The alternator in the coach will probably need upgrading for the increased fan amp draw and finding a fan that will provide the required CFM is an expensive endeavor. The electric fans are starting to be used in heavy duty applications like busses but they typically use multiple fans and have lots of room for the install. The HD fans are normally quite deep so space can be an issue. Jim Bounds at the Co-Op was rumored to have a system in the works but I haven't heard how if it's panned out.
It might be an expensive exercise, but good luck if you go there.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: Electric fan [message #354154 is a reply to message #354147] Sun, 26 April 2020 15:09 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Sounds like you are trying to save parasitic power loss. Best way is to not convert rotation to electric with heat loss and then back to rotation at the fan with more loss through heat. It’s a different story in passenger cars with low GVW they get away with cheaper electric fans, but last time I looked 3/4 and 1ton trucks still have clutch fans, with viscous clutches are now electrically controlled. The difference being the controls control valving for the drive fluid. The Peterbilt style is an electromagnetic clutch similar in action to an AC compressor clutch. Yes you feel the jerk and power rob when they engage. A working stock non electric thermal fan clutch is to a point a variable device only transmitting as much power as needed at the time. Unlike the Peterbilt type, even when they are fully engaged they are RPM limited as the gas engine can rev much higher than a 4 stroke Diesel.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Electric fan [message #354158 is a reply to message #354154] Sun, 26 April 2020 16:50 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Jim Bounds at the COOP has a new aluminum radiator and dual (I think) electric fan setup that he says is cost comparable to buying a new radiator.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com

________________________________
From: Gmclist on behalf of John R. Lebetski via Gmclist
Sent: Sunday, April 26, 2020 15:09
To: gmclist@list.gmcnet.org
Cc: John R. Lebetski
Subject: Re: [GMCnet] Electric fan

Sounds like you are trying to save parasitic power loss. Best way is to not convert rotation to electric with heat loss and then back to rotation at
the fan with more loss through heat. It’s a different story in passenger cars with low GVW they get away with cheaper electric fans, but last time I
looked 3/4 and 1ton trucks still have clutch fans, with viscous clutches are now electrically controlled. The difference being the controls control
valving for the drive fluid. The Peterbilt style is an electromagnetic clutch similar in action to an AC compressor clutch. Yes you feel the jerk and
power rob when they engage. A working stock non electric thermal fan clutch is to a point a variable device only transmitting as much power as needed
at the time. Unlike the Peterbilt type, even when they are fully engaged they are RPM limited as the gas engine can rev much higher than a 4 stroke
Diesel.
--
John Lebetski
Woodstock, IL
77 Eleganza II


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Re: Electric fan [message #354174 is a reply to message #354147] Mon, 27 April 2020 07:49 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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The viscous clutched engine driven fans - temp or electric valved - will run between about 10 percent of engine RPM to a bit over 90 percent of engine RPM. The M - B electric clutched one which Matt refers to moves substantially more air than the OEM, and it's lighter and quieter. Applied sells a kit. So far I've heard of only one failure, which was mine. The internal connection to the valve coil failed someplace. I gave it to the originator of the idea (Tom Pryor) to do some destructive testing. Ain't heard back, but I know he's busy. The Mark 1 Mod 1 that Matt has uses a fairly simple off - on controller which is switched by a temp probe in the engine water jacket. Set points are determined by the probe spec.
Some folks, Pruor included, are investigating a variable speed controller for it, much the same as is used on the pickups mentioned above. This is accomplished by feeding the fan pulsed 12 volts and varying the pulse width. Given the hysteresis in the valve system this results in partial opening, with the amount dependent on the pulse width. You could consider the on - off setup the same, only the pulses are much wider than the reaction time of the valve Smile
I note, the few electric clutches I've seen on big rigs have the fan in a separate set of bearings, not on the crankshaft. The clutch engages all at once, and the shock of the fan mass is eased by the drive belt. I wouldn't want that sort of thing on the front of a 455, I'd fear for the pump bearings.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: Electric fan [message #354178 is a reply to message #354147] Mon, 27 April 2020 10:26 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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Just to throw in my 2 cents worth...i know from our company vehicle testing that going from viscous fan to and electric setup gained 10% more fuel economy even with having to add bigger alternators.

As for the trucking industry alot of the 2020 trucks you will see with closed loop cooling systems and electric fan now. Highway Coaches have been on e-fans now for a couple years now as well.

So perhaps you may need to go to the 100amp alternator but if the fan shroud is done correctly you should be further ahead in my opinion.


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: [GMCnet] Electric fan [message #354182 is a reply to message #354174] Mon, 27 April 2020 10:31 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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I have been running the Electric Fan Clutch for over a year and over 12,000
miles and can tell you the fan does not SLAM on or off.

On Mon, Apr 27, 2020 at 5:50 AM Johnny Bridges via Gmclist <
gmclist@list.gmcnet.org> wrote:

> The viscous clutched engine driven fans - temp or electric valved - will
> run between about 10 percent of engine RPM to a bit over 90 percent of
> engine
> RPM. The M - B electric clutched one which Matt refers to moves
> substantially more air than the OEM, and it's lighter and quieter. Applied
> sells a
> kit. So far I've heard of only one failure, which was mine. The internal
> connection to the valve coil failed someplace. I gave it to the originator
> of the idea (Tom Pryor) to do some destructive testing. Ain't heard back,
> but I know he's busy. The Mark 1 Mod 1 that Matt has uses a fairly simple
> off - on controller which is switched by a temp probe in the engine water
> jacket. Set points are determined by the probe spec.
> Some folks, Pruor included, are investigating a variable speed controller
> for it, much the same as is used on the pickups mentioned above. This is
> accomplished by feeding the fan pulsed 12 volts and varying the pulse
> width. Given the hysteresis in the valve system this results in partial
> opening, with the amount dependent on the pulse width. You could consider
> the on - off setup the same, only the pulses are much wider than the
> reaction time of the valve :)
> I note, the few electric clutches I've seen on big rigs have the fan in a
> separate set of bearings, not on the crankshaft. The clutch engages all at
> once, and the shock of the fan mass is eased by the drive belt. I
> wouldn't want that sort of thing on the front of a 455, I'd fear for the
> pump
> bearings.
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me
> in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Electric fan [message #354197 is a reply to message #354147] Mon, 27 April 2020 17:45 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Most highway busses (Prevost) are 24 VDC or mixed 24/12V. Makes a big difference when powering HVAC fans and cooling fans.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Electric fan [message #354204 is a reply to message #354197] Mon, 27 April 2020 18:50 Go to previous messageGo to next message
Hal StClair   United States
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JohnL455 wrote on Mon, 27 April 2020 16:45
Most highway busses (Prevost) are 24 VDC or mixed 24/12V. Makes a big difference when powering HVAC fans and cooling fans.
The 24 volt alternators used in buses range from 270 to 400 amps-that would be 540 to 800 amps 12 volts. Lots of juice....
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: Electric fan [message #354205 is a reply to message #354204] Mon, 27 April 2020 19:53 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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Sure but we run anywhere between four X 20" to nine X 11" [they pull all together about 230amps at start up and then settle down to around 80amps once spinning if they are all needed].....i can tell you that the 18" fan on my 66 Barracuda street car doesnt draw much or even run that often [its on a stock rad with the old style 45amp stock alternator with a motor that makes over 500hp]

If you really think about it...how much does the fan run? [Any design...mechanical, electric or other]. Realistically its only one at idle or slow speed once the thermostat opens....so without actually watching it, my guess is the fan is only freewheeling at highway speeds.

To each their own....stock works, so does electric with the proper shroud since it will really need to be a puller.


Hal StClair wrote on Mon, 27 April 2020 19:50
JohnL455 wrote on Mon, 27 April 2020 16:45
Most highway busses (Prevost) are 24 VDC or mixed 24/12V. Makes a big difference when powering HVAC fans and cooling fans.
The 24 volt alternators used in buses range from 270 to 400 amps-that would be 540 to 800 amps 12 volts. Lots of juice....
Hal


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: Electric fan [message #354211 is a reply to message #354147] Tue, 28 April 2020 07:35 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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JimK, you are using the electric clutched M-B fan, correct? It is very different from the electric clutches on semis. It has roughly the same engagem,ent time as the OEM one, it is merel;y controlled by engine temp instead of radiator air tep.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Electric fan [message #354213 is a reply to message #354211] Tue, 28 April 2020 08:55 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Yes, I’m trying to get through my old brain that the radiator method of
sensing is better.
Hope this concept will light up one day soon and get enlightened😁

On Tue, Apr 28, 2020 at 5:36 AM Johnny Bridges via Gmclist <
gmclist@list.gmcnet.org> wrote:

> JimK, you are using the electric clutched M-B fan, correct? It is very
> different from the electric clutches on semis. It has roughly the same
> engagem,ent time as the OEM one, it is merel;y controlled by engine temp
> instead of radiator air tep.
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me
> in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Electric fan [message #354218 is a reply to message #354213] Tue, 28 April 2020 13:08 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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jimk wrote on Tue, 28 April 2020 09:55
Yes, I’m trying to get through my old brain that the radiator method of sensing is better.
Hope this concept will light up one day soon and get enlightened😁
--
Jim Kanomata
Jim,

Let me try to work that switch for you. I did work in the cooling group at Jeep for a couple of years.

The reason for the thermostatic clutch on the fan being controlled by radiator temperature is a very simple explanation. It was the least cost method. As a supplier that got beat up by buyers for a one penny per piece price increase, I can affirm that they are that sincere.

Next, why the thermostatic fan clutch at all? One "word" -
CAFE (Corporate Average Fuel Economy)
A typical engine driven fan pulls a lot (~2~4Hp) depending on speed. The power drain is the CUBE of the speed. A bare engine without a fan will turn in much better performance values.

Lots of smaller cars had electric cooling fans years ago. Yes, and most were trans-verse engine so a engine driven would be impractical. That pried the door open.

Then, came along the ECU/C (Engine Control Unit/Computer). As these soon got to the stage where they were observing all the engine's conditions, adding a coolant temperature switch was only adding a couple of lines of code to book the size of a city phone book and another pass transistor on the heat sink. When engine power went up, the fan power had to increase too, so an number of vehicles had to have a fan control module to handle the load.

Then they could loose the **** thermal clutch and the associated calibration issues and warranty. And as an added benefit, not having the fan on the waterpump shaft reduces the load on those bearing and with it off the FEAD (Front Engine Accessory Drive) reduces the load that those components have to address.

Now, I going to intentionally muddy the water just a little...
When running test engines for a client, they were always run with a regulated coolant out temperature because that is what the client specified.
When running a development engine for our own use, we would control the temperature of the coolant in and monitor the coolant out just as a reference.
When I can finally do the study, I am going to change the control on my fan clutch to water in and let the thermostat be the control on water out.

If there is a question there that I did not answer, please ask away.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Electric fan [message #354253 is a reply to message #354147] Wed, 29 April 2020 13:41 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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Matt.

Out of curiosity, what would you typically see on water in temps?


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: [GMCnet] Electric fan [message #354265 is a reply to message #354253] Wed, 29 April 2020 16:37 Go to previous message
powwerjon is currently offline  powwerjon   United States
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What thermostat are you running?

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)



On Wed, Apr 29, 2020 at 11:42 AM Mark Sawyer via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Matt.
>
> Out of curiosity, what would you typically see on water in temps?
> --
> Mark S. '73 Painted Desert,
> Manny 1 Ton Front End,
> Howell Injection,
> Leigh Harrison 4bag and Rear Brakes,
> Fort Worth, TX
>
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