Blower / Fan wiring problem

[Rox Crusher]

I just rebuilt my heater box and installed a new heater core. At the same time, I removed my heater fan switch to lube the cable etc.

I didn’t pay attention to the wiring connections when I disconnected everything and now when I have it all back together I have two problems;

Fan runs on low speed when switch is in high position
Fan runs on high speed when switch is on low position

More importantly, I think the fan is rotating backwards. When fan running on high, with defrost duct disconnected, defrost cable pulled so flap is allowing for defrost.........I put my hand over port where defrost duct is supposed to be connected and I can feel the fan pulling air rather than pushing air out.

What wires did I correct wrong when reassembling ?

 

[mhinchliffe]

Switch the 2 wires on the fan speed selector switch and then reverse the connections on the blower motor.
DC motors will reverse if their polarity is switched.

 

[Rox Crusher]

Switch the 2 wires on the fan speed selector switch and then reverse the connections on the blower motor.
DC motors will reverse if their polarity is switched.

I think the motor itself is wired correctly as there are only two wires.......the ground wire and the orange power wire. Having said that, I may have connected the wires to the resistor backwards. I’m thinking that’s why the motor is running backwards but that’s just a guess on my part.

The low / high speed fan situation I’m not really that worried about. In fact I’ve always found it strange that the first position is high and the second position is low.

 

[66CTBronco]

Resistor direction won’t matter at all. I thought these fan motors were universal because when I rebuilt my heater I drilled the rear cover to get some oil down into the bushing and hooked up to my six amp charger. Only spun in one direction regardless of polarity... ymmv...
C
Btw was glad to see an October 1966 date on the motor matches my dec 66 truck yay!

 

[Rox Crusher]

any additional input guys ?

 

[66CTBronco]

Did you take the squirrel cage blower off the motor? When I got mine running it “seemed” to run backwards but blew air out the vents and defrost I thought that was strange.... but I have heat lol!
C

 

[Rox Crusher]

At the risk of complicating the discussion........

I replaced the original motor with the one from mid nineties Ford F-250. I reused the original fan cage.

 

[Rox Crusher]

I removed the heater box and turns out I had the connections to the resistor reversed so I corrected them.

I also had the connections on the switch backwards but chose to leave those as is so the fan comes on in low mode first.

All good now. The new fan seems to move more air and I don’t know if it’s any louder.

Thanks for the help guys.