How to access Blower Motor in '91 RMW?

Hey Guys,

My blower motor gave up the ghost. I know it's in the dash, but I have no idea how to get to it.

I took out a ton of screws, but managed to get nowhere...slowly...besides get the panel below the glove box off and the wood trim on the dash off.

How do I get to this thing?? I'm good at taking electronics apart....cars....not so much.

I only have one working power window, so it's pretty horrible in the Roadmaster right now.

Thanks in advance.

Did you take a flashlight & look straight up under the dash behind the glovebox?

I followed the wire (the previous owner wired the motor directly to the battery via a switch), but I see no way to get it out....

Three whole screws and it falls out, unless I'm missing something.

You should get a used motor/fan, because the replacements have a shorter fan, and it does not get close enough to the bottom in the intake. It allows a lot of leakage, which reduces the flow of air to the vents.

The back screw is a little difficult to get to with the kick panel, and carpet in the way, but can be removed. the screws only grab plastic, so be gentle when reinstalling them. They should have ieither a 5.5 or 7mm head.

If you wire it back into the HVAC, you may have a more satisfying experience with the system. The issue with wiring it back, and why it is directly wired to the battery, may be the fan control module, which is next to the fan, and held in by 4 screws. I have a few good used ones for sale. You may need the connector(s) to hook it up as well. The HVAC system is really nice when it is working as it was intended.

My story::
Several years ago I bought a replacement blower from the dealer for my Caprice, and it was an entirely different unit than the original (had the white squirrel cage). It fit in the vehicle and functioned, but because it was an 'orphan' replacement, it made 'flute' type harmonic whistles when in the middle two speeds. It drove me nuts. Sorry, but I must have a quiet, "birdie-less" blower on my vehicles.
So I scored a working OEM unit from a forum friend on another board, drilled into each end bearing of the motor and used a hypodermic needle through the drilled holes and refilled the bearing felts with oil. It is still working as silently as the original one. I have done the same re-oiling technique on the blower in my Astro, and hopefully it will continue to give me good service. Got a spare, too. Call me anal, but I just want to have a known, good, "fluteless" replacement sitting in my garage for the day down the road when the current one says 'no mas'. This is my story.
I feel that I should add something here. If any of you guys value a 'quiet' vehicle, you can't appreciate what I was describing (the never-ending flute sounds from the incorrect blower) unless you experience it. It's like having a squeak somewhere in the interior that just keeps going on and on; it bugs the hell out of you because you know it shouldn't be happening and it's grating and it ruins your feeling of having a nice quiet drive. Like I said, if you haven't experienced it, you wouldn't appreciate how irritating it can be. Can you dig it?
Oh yeah, anudder thing... I found that if you are patient, you can get the old, pressed-on cage off of the shaft by drilling a small hole into the closed end of the cage, down to the metal shaft, and squirt some penetrating oil in the hole. Wait overnight & then try prying it up with two bf flatblade screwdrivers on opposite sides. The hole breaks any air lock, and the penetrant leaks into the open areas created by the screwdriver pressure. Worked for me.

Fred Kiehl wrote:

You should get a used motor/fan, because the replacements have a shorter fan, and it does not get close enough to the bottom in the intake. It allows a lot of leakage, which reduces the flow of air to the vents.

The back screw is a little difficult to get to with the kick panel, and carpet in the way, but can be removed. the screws only grab plastic, so be gentle when reinstalling them. They should have ieither a 5.5 or 7mm head.

If you wire it back into the HVAC, you may have a more satisfying experience with the system. The issue with wiring it back, and why it is directly wired to the battery, may be the fan control module, which is next to the fan, and held in by 4 screws. I have a few good used ones for sale. You may need the connector(s) to hook it up as well. The HVAC system is really nice when it is working as it was intended.

Fred, would a fan and fan module from a 91 or 92 OCC work? How about one from a roadmaster sedan or early 90s caprice?

The electronic HVAC requires an electronic fan control module. It is the same from 91-96. I do not know if it is the same for pre 91s.

The manual HVAC has a different fan control unit, which consists of a set of coils, and resistors. They are not interchangable with the electronic HVAC modules.

The fan/motor is the same for all 91-96 B body cars, I do not know if it is the same as pre 91 cars.

Rock auto show different part numbers for a 92 and 95 heater core.
They are not interchangeable? I kinda assumed the whole HVAC assembly was the same for 91-96.

To answer the OP: drop the hush panel (squeeze clips), disconnect the oval connector, remove the three 5.5mm bolts. Replace with new/used. Above info is correct: aftermarket blower cages suck (or don't blow).

For Jim: 91-93 and LT1/L99 heater cores are different.

I believe the 91-93 heater cores are designed for the "quick release" (not so quick PITA) connectors, and the 94-96s have a standard hose clamp.

Fred Kiehl wrote:

I believe the 91-93 heater cores are designed for the "quick release" (not so quick PITA) connectors, and the 94-96s have a standard hose clamp.

Ahhhh, I see. Sounds like some more 'cost cutting' during the Jose Lopez administration.

Dave, when we meet up, I'll show you how to change out the fan. Its actually not that hard (just took 15 minutes or so to access and remove the fan taking my time without instructions.)

That took a bit more than 15 minutes

Thanks to CK, the Beast now has a new fan. Well, a junkyard fan and resistor pack. It all works, with the stock climate control hooked back up. Turns out the stock resistor pack was dying and that's what caused the low fan speed.

The fan came from a '93 Sedan, but it was the same fan as what we pulled out, and it gives plenty of air for me.

We had almost got that door sill out, and then it cracked in two places, so we just broke it into 3 pieces. Much easier to handle now, and I'm not too concerned with cosmetics.

THANK YOU THANK YOU THANK YOU. I could have never done that myself. I'm too damn fat to fit in there anyway.

I got a couple of marching color door sills, and cut/trimmed them like the 94-96 variety. It makes the car look nice, and makes it easier to work on as well.

Whoever designed that all in one door sill/ B pillar cover/ kick panel/ lower c pillar cover should be shot. Like dave said, it came out in a few pieces.
I also unhooked some questionable aftermarket wiring (for alarm and fan switch)
The P.O. had unhooked the fan and wired in a switch with a 30 amp!!!!!! fuse on it. The fan would work for 2 seconds then cut out. So I hooked the new fan into the factory system and got nothing. Then I replaced the blower speed module, and lo, the fan came to life.

There is one more issue. I believe the fan on these cars blows very slowly to circulate the fan in the cabin. Well, sometimes it blows very slowly even when the car is not running. A couple times it turned off when the ignition was turned to off, but sometimes it would keep running very slowly. Is this a problem in the climate control head unit or computer for the climate control, or is this a problem with the ignition (the key is heavily worn?)

If it runs at all without the key in the lock, that doesn't sound good. A roadie guy will come in here & tell you what to look for. Chevys are simple machines, with no electronic controls for the blower. I DO know that solid-state switches (like the transistorized blower control in the roadies) can tend to fail in the 'on' state, so maybe that is your issue.

SON OF A-I just went out for a drive tonight, and the fan came on great, then slowed down rapidly. Turning it up and down again made it come up, and then do the same thing.

Sounds like a bad blower speed module (again)... At least I hope thats what it is. I'm not that familiar with the electric climate control in the roadies. If thats what it is, I guess we'll have to make a trip to speedway and grab several of them.

What happens if the fan is not on the fastest setting (if its on medium or low)? Will it stay on then?

You should be able to turn the fan off at any time the HVAC is off. There could be issues in the control head if you cannot turn the fan off.

The speed control resistor packs are available new (aftermarket) at a reasonable price, and I would paint liquid insulation around the base of all of the coils to keep them from corroding. You can get the electronic modules new also, but they are at least $100.

The easy way to tell if you have a coil resistor pack, or the electronic module before removing it, is that the electronic module has 2 connectors, and the resistor pack has one.

It slows at every setting.

Get your VOM out and start checking volltages.

It almost seems like voltage sag, that the voltage source can't handle the strain? In my world that's a bad MDA, but I doubt that this uses an MDA. Something in the electronic control system? I haven't dug into it.

It has the electronic ones, not the resistor pack (wasn't sure what to call it since all of my vehicles have had the resistor pack with the 3 wound wires.

Have you tried another motor control module? How about another fan? You can run it up before you install it, just hook up the connectors and get a good grip on the base of the fan.

We did run it up. Not for a long time, but we did run it up. We tried the original motor control module and the one CK picked up, the one CK picked up allowed it to spin up very strongly.

If it is the automatic control, it will use a sensor in the dash to determine how fast to run the motor. It is as it says automatic. You should not be able to select a "speed" setting, except in the manual mode. Even then, it is incremental as you press the speed button. If you are running in auto, the motor and internal vanes will give you the temperature on the head unit, at the sensor in the dash. If you lower the temp, the fan speed will indrease until it gets to that temp, and then the fan will slow down to maintain the temp. The fan speed can also increase if the car calls for a lower temp.

I do know how the system works in basic terms.

This is in as close to manual mode as I can get: 60 degree setting, econ on, so no compressor, fan turned up as high as it will go, it spins up great, then dies out a few seconds later.

I think we figured out the problem with the fan cutting out after a couple seconds. The only constant between the 2 fan systems (P.O.'s fan on a switch and the factory system) is the toggle switch which I installed to cut the power to the fan when the car isnt on. I had not tested the fan system after installing the switch, and we know the system worked fine before the switch was installed.

As for the trickle of power occasionally going to the fan when the key is not in the ignition, would this be a climate control head issue or an ignition issue? I imagine the ignition is worn because the ignition key is worn out from being jammed into the ignition.

Other issues notwithstanding, bypassing the switch got the fan working correctly. That might have been the problem all long. Damn.

I'm still not sure what's up with the climate control unit, but I've got air again...and in a wagon with one working window, that's a damn nice thing.

Update #2. it worked for a few seconds while driving, then it went slow. Later on in my drive I was moving the wires around and pulled them a little. That was the magic touch! I pulled on the wires and how hard I pulled dictated the fan speed before it went dead.

I'll replace all the wire I can find, as well as solder the connections the time (no butt joints, which there are 4 in the positive side right now).