Electronic Fan Clutch for 6.5's

[hal stclair]

Not that I need another project BUT a guys got to do what a guys got to do. Anyway, I've been looking for a way to install an electronic fan clutch on
the 6.5 Diesel for a while, actually before I started the swap in the first place. I haven't found anyone that's accomplished the task, probably
because the 6.5's have lost favor with the Duramax coming on line and overshadowing the old IDI motor. Too bad the dimensions of the Duramax won't
work well for our applications but that's a story for another time.
I located an electronic clutch that was used on a medium duty 6.6 Duramax for three years that used the same mounting thread size as the screw on
thermo fan clutch used on the late 6.5's. The fan used is on this truck is 23" and about 2" wider than my current fan but shouldn't be too difficult
to trim to size if needed. I'd love to find a 21" 10 blade reverse rotation blade for it but sourcing fans seems to be very difficult for some reason.
The fan height spacing is within a half inch so the fan shroud should work fine. The mechanics of the swap seem to be pretty well ironed out, just the
electronics need to be worked through.
The GM fan used PWM for control and a hall effect sensor to determine rpm of the fan, all controlled by the PCM. Unfortunately, the PCM used by the
6.5 doesn't have the capability to interface with the fan drive so a stand alone system will be needed. Hayden sells a PWM fan controller that looks
like it may work but the jury is still out as of now. I'm curious what control the GMC Sprinter clutch kit uses. Any thoughts on this from some of you
talented folks would certainly be appreciated.
If it can be made to work as designed, this will be a nice addition for the Diesel folks here.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

 

[jim kanomata1]

Hal,
Contact Tom Pryor and see if the water pump shaft hs the same thread as
the unit. (248)470-9186

On Thu, Mar 15, 2018 at 2:39 PM, Hal StClair
wrote:

> Not that I need another project BUT a guys got to do what a guys got to
> do. Anyway, I've been looking for a way to install an electronic fan clutch
> on
> the 6.5 Diesel for a while, actually before I started the swap in the
> first place. I haven't found anyone that's accomplished the task, probably
> because the 6.5's have lost favor with the Duramax coming on line and
> overshadowing the old IDI motor. Too bad the dimensions of the Duramax won't
> work well for our applications but that's a story for another time.
> I located an electronic clutch that was used on a medium duty 6.6 Duramax
> for three years that used the same mounting thread size as the screw on
> thermo fan clutch used on the late 6.5's. The fan used is on this truck is
> 23" and about 2" wider than my current fan but shouldn't be too difficult
> to trim to size if needed. I'd love to find a 21" 10 blade reverse
> rotation blade for it but sourcing fans seems to be very difficult for some
> reason.
> The fan height spacing is within a half inch so the fan shroud should work
> fine. The mechanics of the swap seem to be pretty well ironed out, just the
> electronics need to be worked through.
> The GM fan used PWM for control and a hall effect sensor to determine rpm
> of the fan, all controlled by the PCM. Unfortunately, the PCM used by the
> 6.5 doesn't have the capability to interface with the fan drive so a stand
> alone system will be needed. Hayden sells a PWM fan controller that looks
> like it may work but the jury is still out as of now. I'm curious what
> control the GMC Sprinter clutch kit uses. Any thoughts on this from some of
> you
> talented folks would certainly be appreciated.
> If it can be made to work as designed, this will be a nice addition for
> the Diesel folks here.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> 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
http://www.appliedgmc.com
1-800-752-7502

 

[hal stclair]

Jim, the thread sizes are M36X2 on both fan clutch and water pump. I'm trying to work out a control system for the electronic fan other than just on
and off. Using PWM should afford that option if I can figure it out.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

 

[jim kanomata1]

On Thu, Mar 15, 2018 at 6:02 PM Hal StClair
wrote:

> Jim, the thread sizes are M36X2 on both fan clutch and water pump. I'm
> trying to work out a control system for the electronic fan other than just
> on
> and off. Using PWM should afford that option if I can figure it out.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> 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
http://www.appliedgmc.com
1-800-752-7502

 

[jim kanomata1]

We're working on a controller for our unit that will do what you're seeking.
Should you develope one soon, let me know and see how we can purchase them
from you

On Thu, Mar 15, 2018 at 6:05 PM Jim Kanomata wrote

> On Thu, Mar 15, 2018 at 6:02 PM Hal StClair

>
>> Jim, the thread sizes are M36X2 on both fan clutch and water pump. I'm
>> trying to work out a control system for the electronic fan other than just
>> on
>> and off. Using PWM should afford that option if I can figure it out.
>> Hal
>> --
>> 1977 Royale 101348,
>>
>> 1977 Royale 101586, Diesel powered,
>>
>> 1975 Eleganza II, 101230,
>>
>> 1974 Eagle Bus 45',w/slideout,
>>
>> Rio Rancho, NM
>>
>> _______________________________________________
>> 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
> http://www.appliedgmc.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502

 

[johnny]

Hal -
What benefit do you expect from doing a PWM controller? (You can think of the current setup as thatwith fairly long pulses) We looked a doing one,
but the projected benefits don't justify the cost and reliability in my opinion.

--johnny
--
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" - ol Andy, paraphrased

 

[Ken H.]

Hal,

I've neither studied nor fooled with those fan clutches, but my OPINION is
that you should be able to use 'most any cheap PWM controller for them just
as if they were motors. PWM is really just a way of controlling AVERAGE
current into a DC motor. The result is the same as if a rheostat is placed
in series with the current input, with a couple of exceptions: The
rheostat reduces not only the voltage and the average current into the
motor but also the peak current. The PWM controller, during the time its
square wave output is ON (at its normal voltage), does not reduce the peak
current. Thus, the PWM controller can probably allow a motor, or a fan
clutch, to produce more torque than would a rheostat.

Johnny Bridges has been working on this very project, so can surely tell
you (US) more than I'll ever know. But, if I had one of the fans
available, I'd rig a way to run it (perhaps on the engine), and use a cheap
controller, similar to this (or cheaper) to experiment:

https://www.amazon.com/dp/B0779RJKYW/ref=twister_B0779QWCD7?_encoding=UTF8&psc=1

Oh yeah: I see in that description that the PWM can be controlled by an
external 5VDC signal also -- that opens very simple temperature control
possibilities too.

Not really much chance of hurting anything, IMHO.

Ken H.

On Thu, Mar 15, 2018 at 8:53 PM, Hal StClair
wrote:

> Jim, the thread sizes are M36X2 on both fan clutch and water pump. I'm
> trying to work out a control system for the electronic fan other than just
> on
> and off. Using PWM should afford that option if I can figure it out.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

 

[hal stclair]

Johnny and Ken, thanks for your thoughts. As for the advantages of PMW control, it should be possible to vary the speed per heating requirements-the
fan wouldn't have to be all on or off. Varying the speed with engine temperature requirements would really be nice. If you look at the Hayden 3655
controller possibly with the 355 temperature sensor it looks like that could accomplish this. An A/C over ride which brings the fan on for A/C use or
a switch to manually turn on the clutch looks to be a useful feature also.
The controller you linked Ken was on my radar (although yours is a more robust one than the one I found there) but I didn't find one with the
temperature sensor of high enough capacity.. The Hayden unit seems to have most everything in one package but is a little pricey. I really haven't
totally figured out the clutches operation to be honest. I don't know if it needs a 5 volt reference for the hall effect sensor which won't be used or
just needs the 12 volt PWM to drive the solenoid. Still trying to get a few more answers from Hayden.
I understand GM uses a somewhat different approach than Ford or Chrysler so I don't know if the Sprinter clutch would be the same.
All fun, helps keep the Gray matter moving anyway, thanks again, Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

 

[Ken H.]

Hal,

From the little research I've now done, it appears that a simple PWM
control can set the ratio of input to output speed of the clutch. The
purpose of the Hall effect output is allow limiting the output speed to a
fixed value (variable by the external controller, of course. Even that
could be accomplished pretty easily by comparing that frequency with an
externally generated signal and applying the result to the 5VDC control of
the PWM. Add in all the other parameters that some manufacturers
reportedly add in and one soon reaches the point that an Arduino, or
similar, makes more sense than discrete logic; i.e., build your own ECU.


Ken H.

On Fri, Mar 16, 2018 at 3:13 AM, Hal StClair
wrote:

> Johnny and Ken, thanks for your thoughts. As for the advantages of PMW
> control, it should be possible to vary the speed per heating
> requirements-the
> fan wouldn't have to be all on or off. Varying the speed with engine
> temperature requirements would really be nice. If you look at the Hayden
> 3655
> controller possibly with the 355 temperature sensor it looks like that
> could accomplish this. An A/C over ride which brings the fan on for A/C use
> or
> a switch to manually turn on the clutch looks to be a useful feature also.
> The controller you linked Ken was on my radar (although yours is a more
> robust one than the one I found there) but I didn't find one with the
> temperature sensor of high enough capacity.. The Hayden unit seems to have
> most everything in one package but is a little pricey. I really haven't
> totally figured out the clutches operation to be honest. I don't know if
> it needs a 5 volt reference for the hall effect sensor which won't be used
> or
> just needs the 12 volt PWM to drive the solenoid. Still trying to get a
> few more answers from Hayden.
> I understand GM uses a somewhat different approach than Ford or Chrysler
> so I don't know if the Sprinter clutch would be the same.
> All fun, helps keep the Gray matter moving anyway, thanks again, Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

 

[johnny]

What yall propose will work. It will be substantially more complex, thus substantially more subject to failure. I simply don't see - on our
gasoline engines - that the benefit will come close to the price whether in money or sweat.
Hal, it wants a separate 5volt supply for the speed output. You'll get - if I remember correctly - a pulse train which represents six pulses per rev.
Ford uses the ground lead to control via the pulse train, I suspect their circuitry is a bit less expensive that way, but it's a guess.
Remember, on a gas engine, the fan will spin as fast as 5K, reducing the load will improve economy, I suspect by a very small amount. On something
Turning as slowly as our coach engines I don't see it's going to make a great difference.
That being said, a three pin 5V regulator will work quite well. I have one with this setup and run the pulses throuigh a divider (flip flop) and then
feed a tach set for a 6cyl engine. Now you have a true indication of fan speed.
All that being said, I look forward to yall's results. I can be convinced

--johnny

--
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" - ol Andy, paraphrased