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View Full Version : need advice/discouragement...electric motor repair (blower) issues///



ryan roopnarine
04-12-2005, 11:22 PM
i managed to f' three things up so far. first, due to age, one of the brush leads came off its solder joint. wasn't manhandling on my part, just was gonna die if handled. this one is a bit deep inside the motor (why oh why couldn't it be the easy to get to one?). second, one of the points on the brush holder broke off. this was easily remedied by the other one NOT breaking off (there's still holder to be bent), so this isn't really a problem. third, perhaps the biggest, in trying to solder the brush wire back on, i burned a small chunk of the blower fan blade off.

in spinning the fan to check for off-balanceness, the burned side SEEMED to generate only a small noise. im hoping it isnt ghetto sounding, but realise the fan spins a lot faster than i can spin it by hand. my problem (potential) lay with the way i repaired the broken off brush lead. after burning the cage blade off (despite my heatsink on the contact point of the iron and blade), i realised that i wasn't going to get the iron in the space (the angle is too obtuse for it to go in without hitting the blades). my solution? push the wire into the little notch it fits in, try to jam it as tightly as it will fit. here comes the questionable part.....i took the hot glue gun, put a drop of glue on the end of a screwdriver, and secured the wire to the point. i took my vom, and checked for continuity......meter reads unity! (meter leads read .3-.4 ohms touching). the brush lead to contact point reads .4, which is usually the case for wire. i decide that hans and fritz had better in mind for my car, so i manhandle it, meter it, unity. put more glue, manhandle, meter (repeat 4x). all in all, the lead to point, as well as lead to commutator read .4 ohms, brush to brush across commutator is .4. i guess my question (s) are these.....

i can't afford a new blower motor......should i start looking for a used one?
can the cage be taken off? this would have prevented a lot of crap.
is the unbalanced condition going to cause bearing failure ( i ghetto-rigged pumped lube into the bearing)
do YOU think (subjective) that four layers of hot glue will hold a semi-stressed wire on through vibration of driving.

Paul in NZ
04-13-2005, 04:28 AM
well ryan have you got any choice?You may as well try it and start lookin for a used one.Hope it works out!

ryan roopnarine
04-13-2005, 09:10 AM
ok. i mounted it up, but didn't put the clamp on the motor. the motor sounds ok, it just has a little, almost inaudible whine. im thinking that its because i replaced the brushes and didn't put a contour on the (ie, they're flat, the armature is very round). could this be the cause? sitting in the car with no director baffle on it produced a tiny bit of air, i guess i have to completely mount it in to see if i wasted my time or not.

oh, ps....
as far as "operation" goes, its spinning real good and fast. inside the car it sounds like a turbine, nice and purposeful, mostly air noise.

SRR2
04-13-2005, 10:19 AM
Ryan, how did you find the condition of the commutator? I'm gonna have to pull out my fan assembly one of these days to remove the nesting materials some critters left behind and as long as the thing is out, I may as well have a go at the brush replacement as long as the commutator is in good enough shape to make it worthwhile. If the commutator is in poor condition, like the one on the web page where the guy describes his brush replacement, I'll prolly just opt for a new blower. So that's what I'm wondering -- what are the chances I'm going to find a serviceable commutator? FWIW, I usually run the blower below "2" on the dial.

Jon K
04-13-2005, 11:01 AM
Ryan contact TheGeak (Jason) he has the blower from his M5 we're parting out. *shameless plug for a friend*

632 Regal
04-13-2005, 11:14 AM
here comes the questionable part......

I think this whole project qualifies.

ryan roopnarine
04-13-2005, 12:31 PM
Ryan, how did you find the condition of the commutator? I'm gonna have to pull out my fan assembly one of these days to remove the nesting materials some critters left behind and as long as the thing is out, I may as well have a go at the brush replacement as long as the commutator is in good enough shape to make it worthwhile. If the commutator is in poor condition, like the one on the web page where the guy describes his brush replacement, I'll prolly just opt for a new blower. So that's what I'm wondering -- what are the chances I'm going to find a serviceable commutator? FWIW, I usually run the blower below "2" on the dial.

i'd have to say that its likely going to be the same. mine is. however, if you clean the carbon off of it, and use a sandpaper stick or pencil with sandpaper on the eraser, you can get it quite serviceable. i certainly wouldn't throw mine away after i cleaned it up a bit.

TheGeak
04-13-2005, 03:36 PM
I have my blower motor for sale. PM me if you're interested. I'll cut ya the bimmer.info special ;)