455rocketv8

Hello All,

The heater blower motor on my 71 98 was growling and screaming for 3 months ... this morning there was a LOUD destruction sound ... then slience ... then a bad sulfer like smell. So I found blower motors to order ... but I can't find a reference to where the blower motor is located or how to get to it.

Can anyone help?

Thanks so much.

jaunty75

This is exactly why you should have the 1971 Oldsmobile Factory Service manual. It has all the diagrams and instructions you need to service this.

This is available all the time ebay, but you can also access it online at wildaboutcars.com. You need to join, but joining is free and well worth it as there is LOTS of information there.

jfb

1 it sounds like the motor burned up and the squirl cage is moving. 2. I might be wrong but is the blower motor over your passenger fender behind your inner fender shield.

MDchanic

1. Remove right front wheel.
2. Remove numerous 5/16x18, ½"-head screws holding plastic fender liner (and small plastic front fender liner extension) in place.
3. Flex liner and rotate it out of the fender area.
4. Unscrew numerous small screws holding fan motor to housing, disconnect ground and hot wires, remove.

Beware: The listed part number at the local auto parts store may or may not match - bring your old one to compare.

- Eric

Allan R

Dan makes an excellent point with the CSM. I actually prefer the OEM books because their diagrams are so clear.

To access the heater motor in your 98 you will need to remove the passenger side inner fender liner to access the blower motor and wiring. It's a bigger job with an AC car than with non because of the extra lines you need to move. When taking out the inner liner you really need the front wheel off, and the car jacked up as high as you can safely do that so the inner liner will come out easier. It may be difficult to remove some of the bolts because the clips that hold the liner in place may be rusted to the bolts. Pre treat as many as possible with a penetrating fluid like PB Blaster for a couple days.

BTW, that's a beautiful car, I really like the 4 door luxury sedans over the 2 door models. Color is fantastic too. Just needs a power polish??

68conv455

Be very careful removing the squirl cage off the old motor so you don't break it.

MDchanic

Otherwise the squirrel will get bored, then angry, and chew up stuff inside your car .

- Eric

455rocketv8

THANK YOU ALL so very much ... it was 19 degrees this morning on the way to work and I was COLD!

I have the Fisher Body book ... odd that the power windows and such are there ... but not the heater blower. Regardless, will order the motor AND the manual today.

THANKS AGAIN !

Byron

MDchanic

I would also recommend cleaning all of the electrical connectors, including the ground ring terminal that screws to the bod and the spot that it contacts under the sheet metal screw.
A tiny wire brush attachment in a Dremel moto-tool is ideal.
After the ground screw is tightened back up, you can spray a burst of black spray paint on the body to prevent further rust there - nobody will ever see it, so it doesn't have to be fancy.

- Eric

455rocketv8

One more question if I may ...

I see parts listing for motor just plain or "w/out a/c".

The pictures look the same ... and when I call the guys are "not sure on a car that old". Any idea if there is actually a difference?

Thanks again.

Byron

MDchanic

In general, the motors are different with and without A/C in GM cars of the period, but I will confess I never ran into one of these without A/C, so I can't say from experience.

- Eric

Yellowstatue

The A/C motor is slightly larger and has a 3/4 inch or so hole in the case beside the windings to insert the rubber hose that comes from the plenum to cool the motor...

Allan R

Yes, as Yellowstatue explained there are differences. The reason you don't see the difference in the web pics is they use a 'stock' photo, which means what you see isn't always what you get.

Ahh Eric! That's because most of the cars in the US had AC. Up here in Canada the vast majority of them didn't. So we're used to seeing them 'plain jane'. Also, just a note on the 98: AC wasn't a standard feature - it had to be ordered as an option. Lots of folks think that all the B/C cars came loaded with power features and AC as standard equipment which is not the case.

68conv455

Yellowstatue is correct.
The instructions on the fan I just bought from rockauto says to hook up the existing vent tube to the hole. It also says, insert the supplied plug into the hole if the vent tube is not present.
In my 68 cutlass application (no AC), I did not have a vent tube so I used the plug.
The new fan also has a much bigger motor than the fan I pulled off. No issues on fit though.

76 Regency

Going out on a limb here but I would think a/c vs non may have something to do with the winding of the motor. An a/c car's "max" setting kicks the fan into hyperdrive...maybe a non a/c motor can't make that kind of speed??

Allan R

Good question John. But based on the units I've pulled in the past I haven't seen much difference. I always thought that extra ventilation was due to the position of the blend doors and coolant bypass. Just guessing though. We could take one out of your car and take a look though...

MDchanic

Only the A/C cars had the relay for the high speed.

The heat-only cars had smaler blower motors which couldn't draw that much current.

- Eric

76 Regency

Haha sure. Trust me if it was simple to do, I would but not the way it's hidden away in there.

Allan R

Haven't we ALL wondered why GM engineered the blower motor that way without putting an 'inspection/maintenance' cover in the wheel housing?

jaunty75

Probably for the same reason GM never put a drain plug on the transmission pan. They figured the blower motor would fail or need maintenance so rarely that it was cheaper to build cars without easy access so long as it could be accessed at all.

With the transmission fluid, changing it was required so infrequently (compared to, say, oil changes) that, again, the greater concern was cost instead of ease-of-access. It was less expensive to build the pans without the plug when you multiply the cost per pan by the number of pans that had to be built. And it's not like you can't change the transmission fluid at all.

Plus, without a drain plug, changing the fluid is a messy job, which would make do-it-yourselfers more likely to take the car to a shop than do it themselves. Some fraction of these people would take their car to a dealer instead of the corner garage, so, voila, a little more money for GM dealers.


Or perhaps none of this is true.

Allan R

Actually GM did get smart with the transmission drain plug - at least with the Saturn SL line (now defunct). The trans not only had a drain plug but a spin on trans filter similar to an oil filter. Changing the fluid is actually easy on that car. May have applied to other car lines in the 90's and up? Oh yes, good thing to note, the occasion drip on the Saturn trans is from the case gasket, not the drain plug or filter.

455rocketv8

Hello All,

The A/C has been "beltless" since I acquired the car ... and it is supposed to be 16 degrees tomorrow and 13 on Friday ... so I am going with the "no A/C" version which seems to be the only one I can find that comes with the wheel.

It sounded an AWFUL lot like the wheel disintegrated as well ...

So, IF I fix the A/C this summer ... I will re-fix the fan motor ... for now ... I'm COLD.

Thanks so much for all of your help ... I will post results ... vacation day Thursday to repair.

Byron

MDchanic

I would not advise this.

The motor might not physically fit.

Most of the time squirrel cage noises are caused by leaves or debris inside of the fan housing not by a broken squirrel cage fan.
You may not need the fan at all.

I would strongly recommend taking the motor out first and bringing it with you to the auto parts store. That way you can be sure that the one you get is going to fit.

- Eric

PS sorry if the punctuation is a little bit weird I'm just learning to use the voice input software on my new cell phone while driving.

jaunty75

Hmmm. The solution to this might be staring us in the face. Perhaps it would be easier and cheaper to just move to a warmer climate.

455rocketv8

Hello All,

Just wanted to say THANK YOU for all of your advice. Replaced the heater motor this morning ... 3 hours with one of them spent pulling a metal shard out of my finger ...

Couple things: I bought 3 motors (Advance let me return 2) in order to make sure I had the right one. There IS a difference for sure in A/C and non A/C ... the motor is larger, the fan is larger, and the cooling hole is there. The original fan was indeed still good and I used this fan on the A/C motor and saved 30 $. There are a LOT of bolts holding on the inner fender !!

It's good to be warm.

Thanks again.

Byron

MDchanic

There ya go! Great work! And, yes, those cars can really throw heat when everything's working right.

And, yeah, there are an awful lot of screws holding that darned liner in, aren't there?

- Eric

Al Graaf

OH that's good!! Didn't know when I did mine. Lucky now I guess

Al Graaf

I think perhaps!

Al Graaf

Hmmmm-only if you don't need AC. Just a thougt.

Al Graaf

Voice of experiene? Don't hold back Allan !

Al Graaf

sounds like you trying to hinder a relationship between other Olds fans and their dreams...hmmmmmm

Al Graaf

That Fisher Body Books was worthless during my restoration-The Assembly Manual yes!

Allan R

Byron, so glad it all came together for you. So now I know there's a difference between the fans. Crap - I'm going to have to check the replacement one I bought a while ago, I think I remember seeing a vent hole in it. Oh well, I could prolly just plug it and use it anyway.

Yup, first hand. Wanna buy a used Saturn? Very well maintained - only used by my lil ol lady; very low miles. (the car, not the ol lady)

Nope, never. Y'all know that.

Majority of really useful stuff to a restorer is CSM and AM. FBM is ok, just have to know how to reference stuff in it.

MDchanic

Just in case she's looking over your shoulder, I'll help you clarify:

Regardless of miles, the ol' lady LOOKS like she just came off the showroom floor, right?

- Eric

Allan R

Hee hee hee, Eric! If she WAS looking over my shoulder, she would be my eternally young and gorgeous trophy wife and STILL be the envy of the showroom l!! I would choose her all over again (not the car, silly)

The car's in really good shape too though....... OH! Did I mention there's a down side to having a brew whilst typing?