Blower motor upgrade with in cab motor

[billyocup]

Was looking at another forum and found a thread about upgrading the heater blower motor on a heater with the motor mounted inside the cab and not through the fire wall. The guy used a 90 Blazer motor, then installed a 3 speed switch and heater switch resistor to make it all work.

Was thinking of trying this for 2 reasons. 1: more efficient motor 2: the Painless harness I got is set up for the 3 speed switch with the resistor and 1 wire to the motor and not the old Hi/Lo 2 wire motor and toggle switch that was stock on the 75.

Was wondering if anyone here had any experience with this or any suggestions or words of advice?????

Thanks - Bill

 

[IOPort51]

just one complication I think, the Blazer motor runs in the wrong direction for the in cab heater. I have thought that it is possible to wire the motor positive to ground to make it run the right way.

Was looking at another forum and found a thread about upgrading the heater blower motor on a heater with the motor mounted inside the cab and not through the fire wall. The guy used a 90 Blazer motor, then installed a 3 speed switch and heater switch resistor to make it all work.

Was thinking of trying this for 2 reasons. 1: more efficient motor 2: the Painless harness I got is set up for the 3 speed switch with the resistor and 1 wire to the motor and not the old Hi/Lo 2 wire motor and toggle switch that was stock on the 75.

Was wondering if anyone here had any experience with this or any suggestions or words of advice?????

Thanks - Bill

 

[billyocup]

IO - according to the thread I was reading, the 90 Blazer motor supposedly turns in the right direction for an inside mount. Here's the link to the thread:
76/77 cj5 heater upgrade blower (in cab) - JeepForum.com

My other thought was to try to hook up the 3 speed switch and resistor to just one wire on the existing motor. Any thoughts on that?

 

[IOPort51]

just one way to tell, for sure, buy one and check the rotation. I can not guarantee but it seems that when I did the research for my 77 the rotation was wrong. but the information was a bit sketchy so please prove me wrong and I will speak well of you to people you don't know.

the resistor is a good idea but I think a rheostat may be even better, do away with a lot of extra wiring.

Word of caution, the blazer fan, more than likely pulls more amperage. I would consider a fused, relay controlled circuit from the battery with the relay controlled by the accessory circuit using 12 or maybe even 10 ga. wire. the existing is 14 ga. which may or may not be heavy enough. The rheostat needs a good heavy heat sink as I would guess this draw 10 or 15 amps DC with not much problem but you really can't determine actual amperage on the load until it is driving the fan wheel and is in the volute moving air.

Please let me know which way the motor turns from the shaft end. If I am mistaken, this is a very good idea!

 

[tarry99]

Was looking at another forum and found a thread about upgrading the heater blower motor on a heater with the motor mounted inside the cab and not through the fire wall. The guy used a 90 Blazer motor, then installed a 3 speed switch and heater switch resistor to make it all work.

Was thinking of trying this for 2 reasons. 1: more efficient motor 2: the Painless harness I got is set up for the 3 speed switch with the resistor and 1 wire to the motor and not the old Hi/Lo 2 wire motor and toggle switch that was stock on the 75.

Was wondering if anyone here had any experience with this or any suggestions or words of advice?????

Thanks - Bill

Billy,

I have heard guys using the later motors like out of a 93 YJ which are supposed to be the same size and are also a 3 speed and have a ton of power & wind.
:

 

[gert]

Billy,

I have heard guys using the later motors like out of a 93 YJ which are supposed to be the same size and are also a 3 speed and have a ton of power & wind.
:

I would like to add to the switch discussion, your switch controls how much voltage your blower motor gets, so your existing motor will not care that you swapped to a 3 speed switch to clarify that portion, I have done the Blazer swap on my 83 and it makes a huge difference

 

[billyocup]

Thanks for the help guys

I got a resistor and hooked that up with the 3 speed switch I had. I hooked the heater lead out of the Painless harness to the high lead off the existing motor and it all worked just fine.

Thanks again - Bill

 

[IOPort51]

so, did you use the blazer motor or not?

Thanks for the help guys

I got a resistor and hooked that up with the 3 speed switch I had. I hooked the heater lead out of the Painless harness to the high lead off the existing motor and it all worked just fine.

Thanks again - Bill

 

[billyocup]

IO -

I used the original motor. May try to upgrade the motor later.

Bill

 

[IOPort51]

I am going to have to do something one day , it blows OK but it is pretty noisy.

When you are using the heater do you pull out the "Air " cable?? It moves a lot more air that way.