Wiper motor

[Concrete-crusher]

Hi my wiper motor which is a DR3 didn't seem to have a lot of strength or torque over the past few years only working on a wet screen, and then a few days ago it stopped altogether. So I have removed it and taken it apart. The brushes are worn but not completely gone, I gave the armature a clean and for now put it back together.

The result is it runs again but not starting immediately and I suspect with no real power.

So is this a sympton of brushes needing replacement, the armature windings shorting out or the field coil shorting?

Also apart from ebay where can you get lucas replacement parts or can't you.

Lastly is there an aftermarket motor that fits the S3

Thanks for any advice Steve

[sakadela]

Hello Steve,
I sent you a PM with the address of somebody in the UK that has all the spares and overhauls these motors.

[john.p.clegg]

Try it directly across a 12v battery.that wil eliminate all dodgy switchs.connectors and wiring.and give you a good idea or the motors condition.
John

[MarkDa]

I think you have answered your own question when you say the brushes aren't completely worn.
Perhaps comparison to pictures of new will help?
Probably plenty of retailers - main thing to check is the throw on the gear wheel.
They're not that expensive when you consider new brush plate is ?12 + post?
Mine must have been changed in the past because the sweep was wrong - you can buy new but i had the post refixed in the right place.
Could be a lack of lube in the tube?

[661]

Alan Turner is the wiper motor man, I'm sure that it's his name with which you've been furnished.

[Concrete-crusher]

Thanks all, on the subject of brushes there is at least 3mm of brush extending beyond the holder on both sides, new brushes would in my opinion only increase the brush pressure on the armiture if for example they extended by 5 or 6 mm

So on that basis I can't see it making a difference, but have I got this thought wrong? I have had other motors needing brushes which also don't look completely gone

Steve

[RichardHawkins]

Steve,

My Elan is an S4 which has been off the road since 1979. The lubricant was nearly solid in the flexible drive between the motor and the wheel boxes. After cleaning, everything moved much more easily. Could this be contributing to your problem?

Hope this helps,

Richard Hawkins

[Concrete-crusher]

Thanks Richard actually I stripped and cleaned the motor and re greased it around 3 years ago when I rewired and fitted a new dash so lubrication should be ok

There is a nasty kink in the rack wire right at the connection to the tube, I'm not sure if it's because of the alignment or a po has bent it, but this time round I will replace the rack also

Steve

[Concrete-crusher]

I am going to try to fix the motor myself in the first instance by replacing the brushes. I have taken some readings with a multimeter which are below and might be enough for somebody to verify if theres another problem. Also the rack is kinked so I will replace that as well. Lastly I'm not sure its an original fitment as most on here refer to DR3 A , mine is just DR3 N square type.

Wiper markings DR3 N
12V 3 64
>>>>>

Motor seems weak and does not start immediately

Armature has 10 segments , resistance between adjacent segments is 0.6 ? , resistance on all opposing segments is between 1 and 1.1 ?

The insulation between segments and shaft is ok , no short circuit.

On the field coil there is a Yellow , White and Red
Resistance between Yellow and White is 18.8 ?
Resistance between Yellow and Red is 10.4 ?
Resistance between White and Red is 8.7 ?
Brushes measure 6mm x 6mm in section and are both 5mm in length.
Brush holder looks like 3mm in depth so exposed brush looks like just over 2mm

Thermal cut out looks ok , but hard to test.

Help always welcome. Steve