The Stovebolt Site Forums The Shop Area The Electrical Bay Fresh air heater wires ?

Are the blower motor wires on a fresh air system routed along side the motor through its own hole in the fiewall?

I do not recall that a wire goes through the firewall?

One wire is probably for power from the fan/blower-switch mounted on the dash.

The other wire is probably a ground wire (attach it to a screw into any cab sheet metal - a screw into a hole in the firewall would be fine).

Thanks Tim! I bought a 12v blower motor and a reostat type switch from jim carter,but I never saw how the old one was hooked up.Jimmy

Here is a clear picture of the wiring. Lead from motor to switch/power. Ground to heater casing.

http://good-times.webshots.com/photo/2950341320102454676ylsmYY

Thanks Brad thats a good shot of what I have.The replacment 12volt I bought also is a two wire and I now understand that one wire is a ground to the heater case or fire wall, but which way or how does the power wire find its way to the dash mounted switch? Jimmy

Jimmy, here is a picture of my stock 6v Harrison fresh air heater which shows the wire connections clearly.
http://www.pbase.com/dennygraham/image/121512986 The hot lead is terminated in a bayonet connector where it connects to the lead that goes to the heater switch.
In case you’re interested here are a few more pictures of it in various stages of disassembly.
http://www.pbase.com/dennygraham/harrison_h-02-47
Denny Graham
Sandwich, IL

Denny that was in nice shape, mine was a rust bucket! I had to do the core and control valve.I used the hammertone dark bronze because it matched my carpet,seat and door panels which are more gray than tan.I also had to get a new blower motor and barrel fan, sorry to say it's plastic, but it was all I could find.I got one of the repop GMC emblem/medalions from jim carter.It looks good, but I had to glue it on because it was made like a dome without the bendable ears to fix it to the heater box.Good pictures! Do you have any of the switch and wires.My originals were missing so I bought the reostat type also from jim carter. Thanks jimmy

Ask and ye shall receive sayeth Loui; http://www.pbase.com/dennygraham/electrical&page=2
It’s pretty straightforward Jimmy, pick up a hot wire from the ign. switch to the heater switch then straight to the bayonet connector to the motor which is grounded by a 4”pigtail to a SM screw on the back of the housing. That’s it.
The original switch for the AD Fresh Air Heater would have been a two-speed toggle switch. They are no longer available and not being reproduced so most of the guys use the earlier rotary switch which you can get from any of the vendors as you're doing.
Denny Graham
Sandwich, IL

Thanks Denny!! A picture is worth a thousand words,in this case ten thousand.I see what my problem is now. On the original 6volt motor the wires are fully inside the cab when the fresh air is mounted.On the replacement 12volt which is longer the wires are outside in the engine bay past the round motor seal.Sometimes I wonder if these guys that make repops and sell them as direct replacements have ever seen the original parts!Until now I had never seen an original fan switch! Simple,solid,and the perfect look for the truck which is why they aren't reproduced, makes mine look like a piece of junk.I'll be searching for one of those new old stock. Jimmy

Denny, what size fuse do you have in that switch? I need to get my wiring connected as well and these pictures are excellent! Thanks!

Don't know what belongs there for sure Kato, I have an SFE14 in mine at 6v. I'll see if I can find the spec somewhere.
DG