Heater Fan Motor

Mtpockets

New member
I saw a post a while back discussing replacement of the heater fan motor in cj's with one from a '73 GMC Blazer. I replaced mine in my CJ7 and wow, I now have a turbo charged heater/defroster. Thanks to whoever passed that info along. I would recommend this upgrade to anyone who hasn't already done it. Evidently there were two different fan motors on the blazer. You will need the shorter shaft, I believe it was the blazer w/o AC.
 
I wish there was such knowledge back in the '80's when I had my '77 Steppenwolf CJ (an artist friend painted a very lifelike likeness of the wolf on the Steppenwolf Live album on each side of the hood.
Now that I have 'Black Betty' a '78 with this knowledge I went in to take care of the defrosting issue only to find the P.O. had already bored out the hole somewhat for a different fan, but not the Blazer one. It took only a little cutting and I was in business the volume of air now overrides any poor design issue of the defroster ductwork.
 
Amen Turbogus. That thing moves some air, but I also understand what 78cj71ton is saying about recirculating cabin air to cut down on window fogging. I just opened the vent as far as I could to try it. It hasn't been cold enough here yet to put through a good test.
 

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LOL!! It would be kind of like sticking your hand in an unfamiliar dogs house. You may get bit!!
I still haven't been able to see how well the new fan will heat the cab. Before I start cutting I'm want to see how it does.
 
My fan blower is not working for the heat and air

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Welcome to jeepz.com.
have you checked for a blown fuse ? Also , you may have a bad blower motor resistor or bad blower fan switch . A motor , switch or resistor will pull more amps than the fuse is rated for and cause fuse to blow . It's likely the fuse is on the same circuit as a relay that feeds the a/c which causes more draw too . Another circuit with excessive draw can feed back to the same fuse and cause it to blow . First check the fuse and change it with the proper rated amp fuse and see if the problem re-occurs . If so , you'll need a wiring diagram to find what's on that circuit that may be contributing to overdraw. Usually , it's just the switch , resistor or motor. If you need to post back , please start a new thread and tell what year , model and engine . Updating your profile to include vehicle info is helpful as well . Thanks for your membership .
 

In reply to the bad fan:
You could also have a bad or loose connector on the blower resistor or even on the fan itself. I had this issue for a while until both fan and resistor finally went out and I replaced them both.

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2000 Wrangler 4.0,I have checked the fuse and also have changed the resistor. I was wondering if I can straight wire it right to the battery to check blower motor,but not sure how to do that.

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So this is a TJ that has many possibilities for heater issues.
The resistor. Whe switched melt as well as the wires.
You could start by cleaning the ground and inspecting the wiring and switch module.
You could jumper 12 V to the motor to see if it is ceased.
Does it work on high speed?

Mods might want to make this it's own thread so it gets attention and doesn't confuse the above mod write up.


JPNinPA
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