I know power windows get weak. I’ve tested 10 or 12 through the years.

If i understand it, the windings & magnet tech for heater fan blowers is the same in principle, so I’m guessing they get weaker over time too.

After 54 years, I think the blower fan in my no a/c ‘66 98 might be wearing out...

It barely blows on low, works o.k. on Med, and works o.k. on high. I know the lack of flow is not the resistor, it’s new. I think that leaves the electric motor itself, since the system is so basic.

Would any of you have pointers toward a drop - in replacement motor?

thanks in advance...

cf

 

I've had more problems with the bearing squealing when it gets old. I think the blower fan & motor is available at many repop places. I've never installed one on a 1966 full size, but I have done a 1967 442. I removed the passengerside inner fender well and the blower motor assembly was easy to access. John

 

Your local auto parts store. Autozone shows availability of a blower motor for your car for $24. You'll have to transfer the fan wheel from the old motor. Rockauto also shows the same Four Seasons motor for about the same price. I'm sure you could get a motor through any of the major auto parts chains (NAPA, O'Reilly, Advance).

 

Before replacing it consider a couple of drops of oil on the motor shaft, cleaning and tightening the ground connection and measuring the voltage at high speed or running a jumper to it and comparing high speed through the controls vs. battery direct.

Yes, they can slow down over time but lowered voltage will give the same symptoms. If it sounds ok a voltage check and an airflow restriction check are worth the time.

Good luck!!!
​​​​​​

 

While brushes and internal bearings can wear, so can external bearings (like outside the motor), low voltage and airflow like said above, and gunk built up on rotating assemblies.

 

The blower motor on my '57 didn't work and so I took it apart and discovered that the grease was almost solid, so I cleaned it up and put almost fresh grease on the shafts and voila, instant repair.

 

Gents,
Genuine thanks for your suggestions about pulling and greasing the old fan. Naturally I saw those comments after I placed the replacement order. The good news is I redid my heater core about 9 months ago and had the system apart. I recall checking the motor then and it seemed ok, but the metal fan was a bit rusty.

Hopefully the new fan will be stronger. I’ll keep the old one just in case. Maybe some of you share my suspicions about modern replacement parts.

Just to confirm on the 65-66 big cars, the best time to replace it is when the fender is off, but replacing the fan is doable with a good couple of 1/4” sockets and patience with the (big) car assembled. I.e. with the passenger fender on the car. Just note that is a Non-A/c car, very simple system, not many screws or parts to go wrong.

cheers
cf

 

Now if you had a '57 or '58 you just lean on the fender and poof, it's out.

 

Yeah, I like those modern cars from 1966...

Still, fan out with fender on? Cool

cf

 

I replaced the blower fan on my '66 non-a/c convertible this morning. I was right that you can pull the fan without pulling the fender. But it's kind of a pain. Sockets & tiny screws love to fall deep down into the fender & get lost. Also a bunch of the screws are hard to reach up inside the passenger fender. It would have been much smarter to do this while the front end was off a few weeks ago, but I didn't have the new fan then...Sigh.

I forgot what a pain this is. My wife did not. She remembered you have to pull the heater box to get at the fan. I suspect she remembers my frustration at relearning this lesson time after time. All the other times I've done this I was replacing the heater core, so I've never really tried to just pull the fan. In those cases, everything was coming out anyway, not just the fan.

Instrutions here should apply to 65-66 big cars 88/98/Starfire without A/C. A/c systems are way more complex.

To replace the fan motor, you first remove the fan and squirrel cage from the heater box in the car. But there's not enough distance between the inner fender & firewall to extract the fan/motor assembly from the car unless the engine side heater box comes out first. What is a pain here, is that it looks like its possible, until you remember it's not. Equally you cannot reinstall the heater box and fan as one unit. The fan/motor assembly has to go back in first. Also look out for the tender brass connections on the heater core, they're not strong.

My recommendation is as follows:
1) Unhook the heater power wire (orange in my case)
2) Remove the 4 or 5 1/4 hex head screws that secure the heater motor and squirrel cage fan to the heater box. Slip it up & forward into the fender so you can access the heater box
3) Remove the 7/16's head speed nuts and screws that secure the heater box to the firewall. With the fan/motor assembly up forward in the fender a few inches, slip the heater box out of the engine bay
4) Remove the old fan/motor assembly from the car
5) On the workbench, secure the new fan to the old heater box. Then take a piece of blue tape or sharpie & make a mark that shows the orientation of the new fan screw holes on the heater box. It's no fun trying to orient this correctly when it's in the car.
6) Slip the new fan/motor assembly back in between then inner & outer fender first, before the heater box.
7) With the fan/motor mostly out of the way, slip the heater box back in and loosely secure all the 7/16's nuts. Once they're all threaded, you can tighten them, but leaving them loose makes it easier to get them all threaded
8) Using your orientation marks to get the fan screw holes lined up with the heater box, put the 1/4 hex head screws back in. I used the blue-tape-holding-screw-to-driver trick for all the blind screws. They're a pain & time consuming.

Short to say. 3 hours to do. When you pull the heater box, consider giving it a clean up in & out and maybe a shot of Satin Black to make it look nice.

Hope this saves some of you some time & pain. Or maybe you guys have something clever missed?

cheers
cf

 

I meant to post this diagram yesterday, but couldn't find it. Here's where the buried screws are for the heater case:

65-66 88/98/S/f Non-A/C heater case screw locations.

There are a couple of buried (i.e. hard-to-reach) screws to attach the blower fan too. If yours is still factory, they're 1/4" hex head screws.

cheers
cf

 

I would damn sure be testing the power supply to the resistor, and from the resistor to the fan; and across the high-speed relay or fuse if the vehicle has one.

I've never seen a fan motor get "weak". I'm not saying it can't happen, just that I've seen heaps of vehicles with voltage drop in the electrical systems, and just as many where the heater core is packed with leaves, debris, mouse nests, etc. that kill air flow.

Voltage drop testing would tell the story for the electrical system, but be sure to include the ground side as well. Hopefully it's not a packed heater box.

 

Power in the system is 14.3 volts plus or minus and the resistor is an NOS part about a year old. My fan was indeed getting old. But I kept it...

 

"System" voltage isn't the issue. The issue is voltage AT THE RESISTOR, and AT THE FAN MOTOR, with the fan RUNNING.