Another blower motor question

[Magnes]

1972 Satellite Sebring Plus. Came with AC but AC is disconnected.

My blower motor isn't kicking on. If I run a jumper wire to the positive connection at the motor, it kicks right on. It squeals a bit then then quiets down. It blows hard through the vents when it is jumped in this fashion.

I've tested the wiring and everything seems to be working as intended. The resistor in the box on the pass side interior warms up. Testing for voltage from the power wire at the fan motor connection shows 11.2 V with the engine off. I've tested the ground and am getting continuity.

It seems like it is getting the power it would need but it's just not kicking on.

This car had set up for a number of years in dry storage before I got it. Apparently it has had issues with the Heat/AC circuit before. When I got it, the resistor was unplugged and in the glove box. The fuse box had apparently melted on this circuit before and the PO had a circuit breaker installed to bypass the melted connection at the fuse for heat/ac. I removed the circuit breaker and installed a new fuse holder in its place because I didn't trust their wiring job. I soldered all connection where I had made the repair. I used the appropriate sized fuse in the new fuse holder. Everything should be working fine now, and like I said, I am getting power through to the motor but no motor. I even tried a different resistor from my parts car. Same thing.

I guess my question is: Could the motor be bad even though it kicks on with a jumper wire? Like it needs too many amps to run through the wiring or something?

I'm NOT good at diagnosing these electrical problems so forgive me. I appreciate any help you can give. Thanks

 

[slepr1]

Since you are getting power to the motor it should work. You mentioned you are getting 11.2 V at the fan. That seems a bit low imo. What is the voltage you are supplying it when you jump it? My first thought would be the motor needs higher voltage at start up. The squealing could be indicative of motor problems. Yesterday I bought a new fan motor for my Cordoba and it cost me $20 from a local parts store.

 

[Magnes]

Oddly enough, I was looking at the wiring diagrams and on a hunch went and pulled the AC/Heat controls and dropped them down. I turned the key and nothing. I wiggled the wires at the fan control switch and boom, it works. Don't ask me why it wouldn't work before... Probably just not good enough of a connection to get the power the fan needed.

Anyway, it works fine now. I am just going to use it temporary and will be dropping the AC/Heat box soon in order to replace all the seals, clean it out, check everything and replace as necessary, and I will go ahead and replace that motor while I have it apart. It's old. It squeaks for maybe a second as it starts up.

Anyway, Thank You Slepr1. I appreciate the tip on the fan. I will definitely be checking with the local parts shop.

 

[Photon440]

Good news on finding the wiring problem. You might not need to replace the motor, just check the brushes and lube it. The squeak is probably dry bearings, you've got a steel shaft turning inside a bronze bushing.