Window lift motor replacement?

[geo]

Originally Posted by Sam410

The motors for my 410 windows work well, but I have had problems with the microswitches.

I only have experience with the later system used on the 412, but here the switches can also prove to be troublesome (as is the case on many other systems of the period). It is really worth taking them apart (watch for any springs and little ball-bearings!), cleaning them up with a contact cleaner (one of the glass-fibre pencils is also useful) and reassembling them — this always worked for me. The other problem on the 412 was that even the later type of motor got very wet and many of the connections suffered corrosion. After rectifying this along the same lines as the switches, I glued builders polythene inside the door to stop any water landing on the motors.

Originally Posted by Sam410

I spoke to Bentley specialist Introcar when looking for new microswitches (which they couldn't supply), who said they tend to junk the Piper system and fit more modern motors when they have to fix them. Might be worth trying them for suggestions?

As I currently have an R-type (anyone want to buy it?!!) I have had quite a few dealings with them and they are a pretty helpful outfit.

George

[RGSchmitt]

Hi all -

"The other problem on the 412 was that even the
later type of motor got very wet and many of the
connections suffered corrosion. After rectifying
this along the same lines as the switches, I
glued builders polythene inside the door to stop
any water landing on the motors."

Don't know if this applies, but an expert on
Imperial (Mopar) window motors found that the
window motors were corroding internally because
the hot motors drew in moisture when cooling,
which collected on the bottom of the casing and
could not escape. Fortunately, these same motors
were used in nearly all Mopars for about 20 years, so easily sourced.

There is also an Imperial owner who offers a
service to rebuild window switches.

Bob

[MYTA21]

Trsut my car, a 409, to have the odd ball units, ie the Piper motors! However that might mean some input from some RR contacts. These are chain driven- noisy. ( Sounds like a port cullis raising!)
Raising the glass is assisted by some coiled spring devices which resemble steel tape measures.

I have not taken anything apart yet, but the problem seems to be that on one window, the motor raises the galss to it closed position. For a couple of times, it will work up and down, never failing in an intermediate position. Then on closing, it fails to reopen-a click is heard.
Wind the screwdriver in the hole and it will work for a while.
So, am I correct in thinking this looks like limit switch?

[412usa]

Kevin,



I had the motors on the 412 rewound about 8 years ago and they still work fine. Is this an option?



Peter

[Kevin H]

Originally Posted by 412usa

Kevin,

I had the motors on the 412 rewound about 8 years ago and they still work fine. Is this an option?

Peter

I guess it might be, if I could get them out! Unfortunately All the motor fixing points are rusted solid. I'll post some pictures of inside my door shortly - do you remember of the 412 has a similar set up?

Kevin

[Kevin H]

As mentioned before, attached are the pics of my window lift mechanism and motor. The red arrow points to the "screw tube"

[Kevin H]

Originally Posted by MYTA21

Trsut my car, a 409, to have the odd ball units, ie the Piper motors! However that might mean some input from some RR contacts. These are chain driven- noisy. ( Sounds like a port cullis raising!) Raising the glass is assisted by some coiled spring devices which resemble steel tape measures.

That sounds very different to the 411 set up (as Sam said).

The 411 uses a screw inside a tube with a slot down one side. There's a bracket fixed to the screw which in turn is connected to the bottom of the window. (I'll post some pictures later from a different PC.) I'm sure it's not helped by the fact that the tube which carries screw is vertical but the motor is mounted horizontally, so the screw/tube has to bend through 90 degrees! But maybe they do that to stop water running down the tube into the motor!

Originally Posted by MYTA21

I have not taken anything apart yet, but the problem seems to be that on one window, the motor raises the galss to it closed position. For a couple of times, it will work up and down, never failing in an intermediate position. Then on closing, it fails to reopen-a click is heard.
Wind the screwdriver in the hole and it will work for a while.
So, am I correct in thinking this looks like limit switch?

That sounds like it is a limit switch issue. You could try Dick Smith or RS Components for something similar. When you do delve into the door can you take some photos and either post them here (or send them to me and I will post them for you - high resolution).

The limit switches on my 411 are fine, the problem is the motors operate very very slowly, but they're not noisy.

[Sam410]

Originally Posted by MYTA21

on one window, the motor raises the galss to it closed position. For a couple of times, it will work up and down, never failing in an intermediate position. Then on closing, it fails to reopen-a click is heard.
Wind the screwdriver in the hole and it will work for a while.
So, am I correct in thinking this looks like limit switch?

I had the same problem, but the other way around - the window would not shut from fully open. The bodies of the microswitches are made of an alloy metal of some sort which had broken up and collapsed (not for the first time it appeared, as it was already glued together with Araldite). These switches are handed left and right, and are unobtainable as far as I can see. As can be seen from the attached photos, I bodged it together with cable ties for a while, though I've now replaced it with a new switch, repositioned and with a new bracket made so that the window striker just acted correctly upon it.

Incidentally, I think these windows are unusual in having a limit switch at the top of their travel. Most windows do not have this, as can be determined by the slight dimming of headlights if you try to close the windows when they are already closed (at least on many modern cars I've tried.) As the problem on your 409 seems to be at the top, it would probably be possible to bypass the limit switch altogether, as the window frame will obviously stop the window going too far. Might be simpler than finding new microswitches?

[MYTA21]

Many thanks for the picture. At least I now know where the switches should
be.
Mike

[Kevin H]

Originally Posted by Sam410

Incidentally, I think these windows are unusual in having a limit switch at the top of their travel. Most windows do not have this, as can be determined by the slight dimming of headlights if you try to close the windows when they are already closed (at least on many modern cars I've tried.) As the problem on your 409 seems to be at the top, it would probably be possible to bypass the limit switch altogether, as the window frame will obviously stop the window going too far.

That Heath Robinson mechanism is amazing - makes the system on the 411 look so elegant!

On proper modern cars they usually use control circuitry to monitor speed of the motor and/or the power exerted by the motor (current drawn) and will stop the motor if it slows down too much or uses too much power.

I don't know how the 409 is wired, but on my 411 the windows were wired directly to the battery, not even on the ignition acc circuit. Nor were there any fuses or relays in the window motor wiring, so I wouldn't recommend removing the limit switch.

Originally Posted by Sam410

Might be simpler than finding new micro switches?

Definitely the way to go IMHO
here's a few 21A micro switches at RS Components

[penman]

Hi
I think a lot of manufacturers originally wired them direct so that windows could be opened/closed while parked up.

There were then a number of accidents where kiddies left in vehicles, who stuck there heads out of the open window, knelt on the up switch and throttled themselves.
Putting it on, a first key click accessory circuit or even the ignition on circuit removed/reduced that risk.

[geo]

I do not know how true this is of the Bristol implementation of electric windows (although I did it on mine), but on other cars, reducing the amount of effort on the electrics to raise and lower them makes them work better. In addition to keeping the outside of the window glass clean, mine benefitted from spraying a silicone lubricant on to the guides in the door frame where the edges of the glass contact.

After all, just think of the amount of effort required to lift a window with a non-assisted window winder, it is asking a lot of that relatively small motor.
George