66 heater blower motor

[Mario #41504]

I have owned my 66 vert for 4 years now.

I'm in the middle of tearing out my heater core. Besides replacing gaskets, core, etc.. my blower motor never worked since I purchased car. I assumed the motor was shot, but since it looks like an original, I wanted to try and save it. Testing the motor by running test lines right to the battery, the fan works. If I switched to the original positive lead with capacitor, not working. I'm assuming that the original wire must be badly corroded because the capacitor is only supposed to suppress radio static right?

[Joe L.]

Re: 66 heater blower motor

Mario-----

Yes, the capacitor is there for RF interference suppression only. I don't see how it could be related, at all, to your motor problem.

[Jack H.]

Probe the wires...

Do you have voltage at the input to the capacitor lead wire? Voltage should change with position of blower switch. If there's no voltage there OR only when the blower switch is in certain positions, it's time to check the dropping resistor that's attached to the heater plenum.

If drive voltage is consistent and switches level in lock-step to the blower switch position, look for a faulty ground at the blower motor. If that checks out, try removing the RF capacitor and jumpering power directly onto the blower motor's power terminal.

You should be able to measure continuity (near zero ohms) across the lead wires of the blower motor capacitor assy. The capacitor runs from the input/output wires to ground via the cap's metal mounting bracket being about 0.25 uF in value.

BUT, if the capacitor has suffered internal dielectric damage, it could be 'leaking' so badly that power to the fan essentially short circuiting its way to ground through the capacitor. In that case, the cap needs to be replaced.

[Mario #41504]

Re: Probe the wires...

Thanks for the input,

Unfortunately, I have my battery and cables out of the car and will not have a chance to try the suggestions you mentioned right away but will certainly give it a go. I have ordered a new capacitor and resistor anyway, still waiting for delivery. I also had thought that if the capacitor was badly damaged it could be "leaking" as well.