Electric seat troubles

[BigPete]

G'day guys. I am having trouble with my electric seat in my 62, and I am hoping somebody here might have a solution. The seat only goes forward and up, and just clicks if I try and go back or down. Problem is, I am 6' 6" and 115kg!!! I got a new (secondhand, but tested) rear coil from T Bird Ranch, as both the auto electrician I took the base to, and John, via email, at the ranch, thought it may have been that. Unfortunately not, as upon installation it is still doing the same thing.

The auto electrician thought the switch was OK, so I guess that only leaves the relay, but I would have thought nothing would work if the relay was shot.

It would be great if somebody had some suggestions, or advice or tips on how to diagnose it. Thanks guys,

-Pete

[simplyconnected]

Do you have limit switches or not?

This motor is typical Ford, having two fields (one for clockwise and the other for counterclockwise rotation). The relay passes Armature power (Green wire) which is always the same regardless of direction. You're right, if the relay does not work, no motion.

So, the switch only passes low-amperage Field power. It feeds the motor's Field windings and the relay coil. Mechanical/magnetic Solenoids engage the motor shaft to power either vertical or horizontal motion. If you get UP, then DOWN must also be engaged. Likewise, if you get FORE, then AFT must also be engaged.

If you get motor rotation in one direction, the Relay must be ok, one Field winding must be ok, and the Armature must be ok. Draw your attention to testing the Red and Yellow wires on the Motor. With a volt meter or test light (and one prod on ground), work the switch and test for voltage at the motor. You should find +12 on Red with the switch in one direction, then +12 on Yellow with the switch in the opposite direction.

If you're missing voltage, trace back to the switch. If you have voltage to satisfy all conditions, your motor's Field winding is shot. I hope this helps and I will wait for your answer regarding the limit switches. - Dave

[simplyconnected]

Big Pete, are ye right? Get a chance to check out your seat motor?

[BigPete]

She's right now!!!!!

Gents, thank you very much for the detailed responses, especially Simplyconnected, couldn't have done it without you!!!! Not that it matters, but no limit switches. As it turns out, one of the windings in the motor looks like it is shot, so I will be looking to get a rewind done here in Australia... American prices for parts are great, but the postage kills it, so exchange is probably not cost effective. Thanks again for your help, and the project goes on!!!!!

[simplyconnected]

...Not that it matters, but no limit switches...

Glad to help a fellow restorer, mate.

Having limit switches does matter because if you have a dirty/broken one, the symptom could present itself as a bad motor. I don't like throwing parts or money at a problem unless they are truly needed.

We hear all kinds of horror stories about the difficulties and challenges restorers abroad face, so I look up to guys like you who turn old junque into jewels. If you ever need something sent, I would be glad to help. - Dave Dare