Hey guys, Been driving my 77 Through summer and fall, Parked her for the winter and a few days ago decided to take her for a spin. When i bought it, never dawned on me to try out the A/C and Heat. Comes to find out the heat works but the blower motor doesnt turn on at all. Low, Med, Hi = Nothing. Found the A/C Temperature Relay under the passanger side of dash and replaced that and the L shaped connector that attaches to it and still nothing yet the electrical to the L Shaped connector has 12.4V running through it. Located the blower and checked all connections there as well and nothing, not even low speed fan or hi speed fan. Checking for broken wires and blown fuses or relays but nothing. Any ideas? Much appreciated.

 

Sometimes if the motor gets wet, the brgs. will rust and it will not turn. If you are getting current to the motor either the motor is bad or the brgs. are rusted solid. I had the brgs. in my blower motor start to rust on me and it screamed every time I cut it on. I ended up replacing it which was not an easy job since my truck has the AC evaporator coil in the way. I recommend replacing your heater coil, AC evaporator, expansion valve, and AC suction/discharge hoses. There is no way to access the blower motor from under the dash without removing the AC evaporator coil and heater coil. Also, be VERY careful when taking the fan off of the blower motor shaft! If you bend the fan, it will cause it to vibrate while running. The best way to remove the fan is to remove the set screw, then take a grinding bit and taper the end on the blower motor shaft like the end of a pencil. You may have to apply some penetrating oil and tap the fan down further on the shaft so you can taper the shaft; then soak the shaft w/ PB blaster or WD-40 for a while, after which gently tap the shaft with a hammer and the fan will pop right off. If you do not taper the shaft, the hammer will flare it causing it to prevent the fan from coming off. If you do this, you should be fine.

 

Ok, well im going to look into that tomorrow morning but the one thing i forgot to say in the last message was the A/C temperature relay that i had replaced, the one Before this new one i installed worked if you wiggled the pig tale that conencted, almost like either it has a loose connection inside of it or one of the wire on the old pigtale had a loose connection. The relay also would get warm so if i turned the heat on for like 5 minutes, at the five minute mark the relay warmed up so much i would just about burn your hand so i figured if i replaced the relay VIOLA! it would work but that has since happened. Thought the new relay was defective and tryed to go back to the old relay and now nothing works so i dont know if i fried something or what but tomorrow im going to test for power on the blower end of that wiring scheme and see if the blower end after the relay is getting power or not. I appreciate all the help i have gotten here guys, thanks!