Blow Motor Issue

The blower motor in my Skylark has not worked in nearly 15 years. I always thought it was the blower motor. I replaced it a while back and it still doesn't work. Before it went out I recall it always blowing and wouldn't change speeds.

The fan switch on the dash feels loose. Do you think it's the switch or the relay? Is the relay on the center of the firewall the one for the blower motor? Does the blower motor need to be grounded? I only recall one wire plugging into the motor.

Thanks for any input.

 

Check for a ground running to the firewall. The relay on the firewall only affects the high speed position.

 

On my 68 Electra with standard ac the relay did in fact control the other speeds as well. I didn't realize it was an issue until I had the relay in my had one day while I had my neighbor changing speeds inside the car. The dang thing zapped me from a short somewhere inside the black block of plastic that made up the bottom of it. 18 bucks from Napa later and its FINALLY working as intended.

The way you can tell if its the switch, resistor or the relay causing the problem is by having someone go through the different speeds while using a tester light right there at the connections to the relay or resistor itself. If it changes like it should the problem is in the relay.

 

if you take apart the switch be extremely careful because it is super easy to break the little metal tabs holding it together.

The blower motor does have just one wire going to it but the relay controls all sources of electricity going to that wire. My advice is just to run a tester light on all the connections going to the relay because that was the exact problem with my car.

 

Thanks for all the input...answered all my questions! Hopefully I'll have it done this weekend.

 

Negative --on a 70 Skylark the relay only controls the high blower speed. The other blower speed circuits do run to the relay. If there is a meltdown in the relay itself, or a connecting plug, it is true that this can have an effect on the other speeds. The resistor array controls the non high speed position. If it is an AC car, the array is under the hood in the AC box. If it is an non AC car, the array is under the dash.

 

So I installed a new relay and still no go. I can hear a "click" when I turn it on high....but that is all. Do you think it may be the resister? One of the prongs has rust on it. Originally thus wS an A/C car. Now it had a delete panel. Am I missing something?

 

Take a pic of the blower motor area on the passenger side of the firewall. I want to see if the ground wire is in place.

Do you have a good ground for the relay with the sheet metal screws in the firewall? Obviously one screw is currently missing.

 

Ground wire? The relay clicks when I turn the fan on high. The relay is shaped differently...the mount is wider and upside down...only one screw fits. I plan to cut a hole in the delete panel to mont the resister when I can get everything to function. Thanks for your help. Let me know if these pics help:

 

Another view.

 

Is this the ground wire?

 

Yep, that's it! But that one grounds the whole car.

 

The braided ground usually goes from the firewall to the passenger side head. The blower motor ground wire may be behind the delete plate on the firewall.

 

Got it going. There was no ground wire going from the blower motor to the firewall. Thanks for your help!

 

Be careful that you do not short that thing out! In your group of 3 pictures I can see your 3 lower fan speed resistor just hanging naked by the valve cover/hood hinge, it used to be safely mounted inside the a/c box that was deleted.

 

Thanks for that. I have it mounted in the a/c box again.

I now have another problem. I have all 3 speeds but it will not turn off. and my selector isn't functioning. Any suggestions?

 

I know in some models with AC, it was never designed to completely cut off. Do all of the speeds work and change the air flow rate?

 

Well that's good news. I do indeed have all three speeds. But I am only getting air through the floor vent. When I try to get the vent or defrost working....nothing changes.

Is the selector vacuum controlled or electronic?

 

There are vacuum controls and there is a cable/wire control that runs behind the radio.

 

Could be that vac hose from the 'canister' on the firewall to the carby is disconnected? I had that problem on my '69 AC 'lark.
With hose off all I got was air from the floor outlets, hooked the hose up and all was working as it should.

Cheers

Chris