Blower Motor Review: Four Seasons 75089, a worthy replacement!

[Salvagedcircuit]

My original OEM AMC blower fan started making unpleasant squealing sounds and did not output much air on the lowest and second lowest fan setting. After removing the fan, I noticed it did not freewheel very much. A simple hand spin would lead to a stopped fan in about 1/2 rotation. Not a good sign. The plastic blower wheel was also melted a bit across 3 fan blades, indicating there was another problem along the 37 year life span. The rubber air tube and blower surround gasket were still in great shape, which is pretty incredible.

 

I took the tube out and lubricated the rear bushing on the fan. The original fans use bushings, not the ever present ball-bearings of most modern day fans. Adding oil certainly helped, and with a hand spin, resulted in slightly more than a full turn before stopping. Still not a great result. It is possible this fan motor could go for another few years if I was able to get the plastic blower wheel off safely and properly disassemble and lubricate the fan, but I was not able to remove the blower wheel.

 

After looking around, there are a lot of replacement fans available. However, the designs are not consistent. 

 

1. UAC BM00007c is a bad design, and features holes on the rear face of the motor, allowing water and debris to enter the rear of the fan. The hole for the air tube also looks too large, as stated by some reviews.
2. TYC 700126 blower has a connector embedded into the motor housing and has the air hole clocked wrong, so the cooling tube will not reach.
3. Unimotor 12474 looks like a worthy successor but does not include the plastic blower wheel or connector. I believe this is relabeled as a Four Seasons 35474.
4. Four Seasons 75089 features a unimotor motor with the correct hole size for the rubber air tube and is sealed from the back like the original fan. I believe this kit uses the above unimotor 12474 and just adds a blower wheel. Luckily, autozone still sells this fan and it seems readily available.

 

Plastic Blower Motor Wheel: Four Seasons 35534, BW9334, BW2098, 7135534, 70102. These should all be the same.

 

Comparison of the new 75089 fan vs OEM:

-0.5in shorter in height

-No gasket included

-Same connector as stock

-Correct 19mm air hole diameter, correct location

-Same 3in height blower fan

-Same 6in dia blower fan

-Blower fan Held on by crush washer instead of spring clamp

-stock blower wheel: 32 blade

-New fan blower wheel: 44 blade

Includes Canadian Maple Syrup 

 

[ghetdjc320]

I’ve been using this blower motor for several years and it works excellent. Also has less current draw than stock. I don’t recall the numbers but iirc, it was about 30% lower amp draw with at least equal if not higher airflow. 

[Salvagedcircuit]

2 hours ago, ghetdjc320 said:

I’ve been using this blower motor for several years and it works excellent. Also has less current draw than stock. I don’t recall the numbers but iirc, it was about 30% lower amp draw with at least equal if not higher airflow. 

Very, ahemm, cool!

[89 MJ]

4 minutes ago, Salvagedcircuit said:

Very, ahemm, cool!

I see what you did there

[ghetdjc320]

56 minutes ago, Salvagedcircuit said:

Very, ahemm, cool!

[AnotherOldJeepGuy]

Thanks, glad to see this post!  I am pretty sure mine is going to need replaced sometime soon.  I replaced the thermal resistor block about 6 months ago when I lost all but high speed.  With the new resistor block I got back all 4 speeds, but lately I have to switch to high, or high-1 to get it started, then I can dial it down and still get the slower speeds.  And sometime the fan gets a little noisy for a while when I start it, but not that often (yet)!  So, it's on the list.