Piper electric windows on 410

[David C]

I have finally got around to sorting intermittent window operation on my 410. Although Piper electric windows were fitted to a fair number of Bristol cars I have not seen a wiring diagram for their use so attach the one I drew to make sense of their operation.

If anyone is interested I can post a few hints on stripping the mechanism and motor.


https://www.bristolcars.info/forums/...1&d=1768150924

[Sam410]

Thanks David, I can foresee that being useful!

My Piper windows have been mostly reliable (grasps tree), the only issue has been with one of the limit microswitches and getting it correctly aligned after I had to replace one on the driver's side.

Do you mind if I share your diagram with a chap I know restoring a Facel Vega with Piper windows?

[David C]

Very happy to share the diagram. It would be nice if my name stays with it.

I don't know if the Facel Vega has the same motor. There is another Piper motor for which I found a diagram on line that has two field coils and three microswitches with a "last inch" switch.

If you do end up servicing the Bristol unit there are a few points that may help.
The lower chain gear needs to be removed to get the motor off the back plate. There is no room to get a spanner or socket on the bolt that retains the tapered pin. I just managed to get a BA box spanner on, undo the nut until level with the end of the thread and then use a parallel punch to break it free.

Stripping the motor is easier once you understand that the key is to remove the field coil. Remove bakelite side plate and unsolder the two coil wires then the coil can be levered out. It has a locating pin on one side so can't be tilted.Once the coil is removed the top screw that retains the gear housing can be removed. Once the housing is off the split pin retaining the worm gear must be removed before the armature can be withdrawn.

[Kevin H]

David,
Would you mind sharing a photo or two of the motor itself, before you opened it up - I'd like to compare with what is on my 411.

[David C]

Try these:

https://www.bristolcars.info/forums/...1&d=1768814262

https://www.bristolcars.info/forums/...1&d=1768814262

They are both of the driver side unit. The passenger side is a mirror image.