fixing noisy blower motor

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photo_van
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fixing noisy blower motor

Post by photo_van »

As usual, this site rocks! My blower has been making intermittent noise for a couple of years now. Finally started making bad noise all the time at the end of this last three week dust fest of a road trip. So I searched here and found this;
CaptSquid wrote:Well, it was posted on the <rule6b> website, but since we don't need no stinkin' Rule 6b...

(This works on ALL years)
You'll need:

1 -- sharp knife (for removal of conformal cover on later years)
1 -- 7mm (I think) nut driver


AND

1 -- new blower moter
1 -- blower wheel (we call it a squirrel cage fan)

1. Remove both overflow tank and washer tank. Empty contents into separate jugs. Now is a good time to clean out the overflow tank. I didn't drain
2. Unplug wire to ground lug at the 2:00 o'clock position AND the power cord. no ground lug on mine
3. (on later models) CAREFULLY cut the conformal coating around the motor on the dotted line.
4. Remove the hex-headed screws surrounding the blower motor. DO NOT LOSE THE GROUNDING LUG!
5. CAREFULLY remove the blower motor and blower wheel. The factory wheel is plastic. The replacement wheel is metal.
6. Install motor and wheel.
7. Reinstall screws and grounding lug.
8. Plug in motor and ground.
8a. Check motor for proper operation.
9. Replace overflow and washer tanks and refill.
10. Close hood.
11. Clean up and replace tools.
12. Consume barley pop and pat self on back.
Totally spot on! It's a bit intimidating at first, but what looks like a hard plastic housing is actually soft rubber, easily cut by a sharp utility knife (just cut between the two little ridges that run circumference of the front of the unit. A very slight Chinese puzzle but you can get the motor and fan out in one piece.

Rather then taking the 2 hours to drive to town and back, and due to the fact I'm cheap and don't like to throw things away, I opted to fix the old one. If it's making noise, there is a good chance that the motor bushings are dry and or gunked up.

I really kick myself for not taking photos, but if you are the kind on guy that likes fixing things, you don't need them.

Remove fan from motor shaft
Remove spring/retainer washer and thrust washer from shaft
Straighten the 4 sets of bent tabs holding the motor halves together
Pull halves apart
Remove armature from remaining half
Blow all the dust out of everything
Clean bushings and bushing surfaces on shaft (the bushings are oil impregnated and are surrounded by a material to be saturated with light oil, I would keep any solvents out of there)
Saturate said material with light oil and dab a little grease in the bushings
Check the brushes (mine still had a lot of life)
Insert armature back in the brush side of the housing (you'll need to hold the brushes back)
Put housing halves back together (the magnates are really strong so this can take a bit of futzing)
Flatten the spring/retainer washer with a hammer (or use a new one if you've got it) an press it and the trust washer into place.
Press the fan back on the shaft and put the whole thing back together

In less then the time it would have taken to drive to town, it was done and I have $50 left over for beer!!
1998 AWD/4WD
4" lift, 31x10.50's, NP 242j/c hybrid, 4.10 gears, S10 front disconnect, rack & pinion steering, trans cooler, rock sliders, ARB fridge, house battery and 100w solar, swing out rear rack with foldout camp table, bed and passenger swivel chair
dirt bag camping rig
1981 Toyota 4x4 pu
1974 John Deere 710
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