blower motor problem

[Mo]

Well, it was -2* yesterday and the heater didn't want to come on. Great.

So in the process of sliding the switch from defrost down to heat, noticed it kicked on for the AC setting...

Questions:
1. Same blower motor for heat and AC, right?
2. Anyone else have this happen where the AC setting turns the blower on, but the heater setting doesnt?
3. How much of a PITA is this going to be to swap out if it's the HVAC switch?

[joe]

Originally posted by Mo:

Questions:
1. Same blower motor for heat and AC, right?

Can't help on the fix but the heat and AC each have their own separate blower motors.

[Mo]

thanks for the quick reply.

Not the answer I wanted, but thanks.

Looks like it's going to be a cold day with the multimeter.

[Hand's End]

This happened on mine a couple months ago. The heater blower locked up when the magnets inside came loose and locked armature. This blew the thermal fuse located inside resistor assembly, which controls the different fan speeds.

The fuse marked heater blower on fuse panel is actually the AC blower on my '89, not the heater blower.

Anyway, I got a new blower motor at Advance Auto that was similiar enough to work, but not same as original. Original was vented, this one isn't. Around $30 I think.

The resistor assembly is mounted on the plastic heater core box passenger side engine. The positive wire comes from it to the blower motor. If you take it apart there is a thermal fuse inside you can replace with one from Radio Shack. Part # 270-1321, $2 I think. Cheaper and easier than finding a new resistor assembly if you are handy with a soldering iron. You can test the fuse with your meter to be sure it's bad.

Thanks to member fitron74 for passing this info to me originally!!!

[ January 29, 2005, 07:57 AM: Message edited by: Hand's End ]

[andy d]

try turning the heater control onto high, then give the fan motor a rap with a screwdriver handle. This has worked for me many times. the brushes stick. If no joy then try the other stuff.

[Hollywood Dave]

And if that doesn't work get a bigger screw driver!!!

[HOOT]

Check fuse.
Pull motor out if possible.Mine had frozen itself into a huge ice cube last month.Have no idea how it happened other than it worked great that day driving into work(35 miles) during a hard snow.14 hours later in 10 degree weather with the snow still falling I found I had no heat for the drive home.Longest and coldest 2 1/2 hours I have ever drove.Following morning discovered it frozen solid and the fuse blown. All is well now but it still baffles me how it happened.

[Mo]

Well, a few quick smacks on the blower motor and it was spinning again.

Took it out, sprayed the inside of teh motor gently with some WD40 and put it all back together. Works better than before.

thanks guys.

[andy d]

doncha love the cheap easy fixes

[Mo]

esp when the WX makes it into the double digits!!!

[GWChris]

It'll probably do it again, mine quit in the ice a couple of week ago. The brushes stick in their sliders, and the armature contacts get all gunked up. Take it apart when it warms up a little bit, and free up the brushes - use a small srewdriver end to clean out the grooves on the armature contacts, and scotch brite the surface (gently). Spray it with brake clean to clean it up. If you want to take the armature out of the front plate/bearing (you don't need to), be very careful - use a file/scotchbrite to clean off the shaft so it does not damage the front bearing, and don't force it through. If you push the spherical bearing out of it's spring retainer, the party's over (well, not rally, but that's another story...)