Heater motor operation

V8 Bob

Well-known member
I have what I believe is a '42-'48 Ford car heater. The switch has 4 positions for what looks like indirect and direct, F (fast) and S (slow). Question-does the motor have 4 speeds in one direction, or two speeds CW and two CCW? Just how does this unit work? I have several service and reference manuals, but heaters are not covered in any of them.
Is there a direct 12 volt replacement motor available, or one that can be adapted? Thanks.




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2 speeds each way. I eventually figured mine out by hooking up pairs of wires to a battery until I had forward and reverse (color code looong gone). Once attached, the slow position just adds in the resistor.
Find a sympathetic NAPA person who can locate the catalog for heater parts...they list motors by size, shaft characteristics, etc. I don't know it there are any suitable ones!
 
V8 Bob - I believe you're correct on the heater age. It's just like the one I have in my '46 Tudor. I think you'll find the motor is 2 speed, two directions. I have used a voltage reducer on mine which I got from Patrick's Antique Auto Parts. It reduces 12v. to 6v. quite nicely but does generate significant heat. If you use one like this, be sure to mount it with sufficient space around it to allow air flow. Also, dont forget to change the bulb inside the knob to a 12v. one. Good Luck! Henry.
 
Thanks Bruce. I tried running the motor but it's shot, as all 4 wires act open.
So...in direct, the blade fan pushes air out the front, and indirect allows the cage to force air out the top for defrost? :confused:
 
V8 Bob - I believe you're correct on the heater age. It's just like the one I have in my '46 Tudor. I think you'll find the motor is 2 speed, two directions. I have used a voltage reducer on mine which I got from Patrick's Antique Auto Parts. It reduces 12v. to 6v. quite nicely but does generate significant heat. If you use one like this, be sure to mount it with sufficient space around it to allow air flow. Also, dont forget to change the bulb inside the knob to a 12v. one. Good Luck! Henry.

Henry,
Thanks for the info. My motor is bad, so I'll look for a suitable 12 V as the heater is going into my '40 which will be 12 volt. ( I'd like to use a '39-'40 heater, but their prices are through the roof at this time!)
 
There is no such thing as a 12V reversing motor .You can find a 12 V from a 56 up car it will be the same size and would work for either the heater or defrost depending on it's direction .The best bet is a resister on a 6 V reversing motor.However there is a guy who used to sit on the barn who says he can make a 12 V one way work both ways .The 48 heater was different in that it only went one way and the heat was controlled by a by pass. Johnny.
 
I have the same heater in my '40 (yes, I know, but it sure keeps me warm), and it has two speeds in either direction as mentioned. Has the same switch shown above, but without the defroster knob, which is instead mounted at the top left side of the heater case. The odd thing about it is that the knob is constantly illuminated when the ignition is on (powered through the ignition switch), goes out when I switch it to "Fast", and shines dimly when switched to "Slow" in either direction. I assume I have it wired wrong, but it is functional, and I haven't yet run it down with a volt meter. Seems to me it should be dark at the off position, lit brightly at the "Fast" positions, and dimly at the "Slow" positions. Anyone have any info on this, or do I have something bizarre and inexplicable going on here?
 
OldDad - It sounds as though you may have the polarity reversed to your heater. My heater knob is dark in the "off" position, dim in either "slow" position and bright in either "fast" position. I followed the wiring code in the replacement wiring set I purchaced from Mac's about two years ago. Try revefrsing the "Hot" and "Ground" wires. Good Luck!
 
Thanks Henry, sounds very plausible and I'll give it a try. I wired this up 25 years ago with only the old frayed wiring to go by, and the car sat until early this year. Figured I had it wrong.
 
awhile back a barner posted the direct 12v replacement heater motor for 40-48 ford was napa # 655-1022 made by belkemp..12v 1/4 shaft...
 
I have that heater in my truck, I need new or good used knobs like those. Anyone know where to get some? I have not seen re-pops.

thanks.
 
If having the "look" of an original heater is all you want but for a 12v system, I mounted a new 2-speed heater behind the outer skin of the 42-48 heater - the heater came from one of the aftermarket AC suppliers. I cut out a portion of the bottom of the heater box to allow heat to escape from the enclosure - you can just see it in the pics. The doors can remain shut at all times if you want.

It works great and you could modify it for defrost ducks if mounted upside down from what I've done.
 

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I have that heater in my truck, I need new or good used knobs like those. Anyone know where to get some? I have not seen re-pops.

thanks.

Here's the whole control set used on Ebay: http://cgi.ebay.com/ebaymotors/1942...r_Truck_Parts_Accessories&hash=item4aa63922d7

Here's a new defrost knob from Mac's: http://macsautoparts.com/early-v8-w...ger-51a-18562-c/camid/F30/cp/JS0R3CHL1076840/

Here it is from C&G: https://secure435.hostgator.com/~dlvry40/ufolder/ShowProducts.php?c=1&s=34&g=284&t=1670&tn=
 
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Thanks to all for the very helpfull info and part numbers. I will be heading to the local NAPA soon to check out/purchase that 655 1022 motor.
 
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