Wiper motor brushes
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Wiper motor brushes
I had a wiper motor pack up today. For once it was after the MOT not before.
I guess worn brushes was an understatement. Both brushes had worn completely and on one side it had continued to work using the arm as a contact until the arm wore, and wore through and kept going until the arm was so short it didnt reach the commutator anymore
I tried a couple of places for brushes but gave up after 2 calls as it was 5pm... I did get offered a recon motor at over £60 plus VAT and delivery
So 1 new brusholder froma bit of tin plate (Blue Peter would be proud)
So heres the tip - keep hold of yopur old Dynamo brushes! They are easily cut into different shapes.
It works very well - plenty of force and runs the wipers on a dry screen. It used to struggle on a wet screeen, but now we know why.
I guess worn brushes was an understatement. Both brushes had worn completely and on one side it had continued to work using the arm as a contact until the arm wore, and wore through and kept going until the arm was so short it didnt reach the commutator anymore
I tried a couple of places for brushes but gave up after 2 calls as it was 5pm... I did get offered a recon motor at over £60 plus VAT and delivery
So 1 new brusholder froma bit of tin plate (Blue Peter would be proud)
So heres the tip - keep hold of yopur old Dynamo brushes! They are easily cut into different shapes.
It works very well - plenty of force and runs the wipers on a dry screen. It used to struggle on a wet screeen, but now we know why.
Ray. MMOC#47368. Forum moderator.
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
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where to break down next?
2013... managed to seize my 1275 just by driving it round the block
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block
- Scott
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Incraydible work !!
Scott
[url=http://img133.imageshack.us/img133/523/bo16vy.jpg]1948 Series MM[/url]
[url=http://img133.imageshack.us/img133/2484/dcp001046qp.jpg]1962 1000[/url]
[url=http://img207.imageshack.us/img207/9625/19705bp.jpg]1970 1000[/url]
[url=http://img137.imageshack.us/img137/7259/nullabor25ns.jpg]1959 Van[/url]
[url=http://www.morrisdownunder.com/forum/index.php]Aussie Forum[/url]
[url=http://img133.imageshack.us/img133/523/bo16vy.jpg]1948 Series MM[/url]
[url=http://img133.imageshack.us/img133/2484/dcp001046qp.jpg]1962 1000[/url]
[url=http://img207.imageshack.us/img207/9625/19705bp.jpg]1970 1000[/url]
[url=http://img137.imageshack.us/img137/7259/nullabor25ns.jpg]1959 Van[/url]
[url=http://www.morrisdownunder.com/forum/index.php]Aussie Forum[/url]
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The commutator only had about half its thickness left.. which is quite good after 43 years, but I was bearing in mind that the wear on the commutator would have been higher due to arcing on the brusholder arm.
With the repair it will mainly depend how well the brushes last, as I expect the comm will still outlast the brushes, but I reckon 20+ years or 10 years if it's used as a daily driver.
Electric motor brushes are normally 'fine tuned' by altering the ratio of copper and carbon to get enough life (ie now they use the cheapest material they can get away with whilst still meeting the spec )
With the repair it will mainly depend how well the brushes last, as I expect the comm will still outlast the brushes, but I reckon 20+ years or 10 years if it's used as a daily driver.
Electric motor brushes are normally 'fine tuned' by altering the ratio of copper and carbon to get enough life (ie now they use the cheapest material they can get away with whilst still meeting the spec )
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Yes, very good. I wonder if a modern equivalent would last 43 years?
It's a "chicken & egg" situation with that comm. now. State of comm. will wear down brushes which in turn leads to arcing from holder to comm.
I seem to recall carbon brushes being graded and care had to be taken with this. Too soft - rapid wear of brush, too hard - rapid wear of commutator.
I also remember being told that they are called brushes because that's what they originally were before being made of carbon - something like that anyway.
It's a "chicken & egg" situation with that comm. now. State of comm. will wear down brushes which in turn leads to arcing from holder to comm.
I seem to recall carbon brushes being graded and care had to be taken with this. Too soft - rapid wear of brush, too hard - rapid wear of commutator.
I also remember being told that they are called brushes because that's what they originally were before being made of carbon - something like that anyway.
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What were you thinking of!
I was thinking that I ###### wish I'd never bought this 4 door. Darn thing is going to cost me money unless I try really hard.
ps - the 4 door is for sale (well it will be next weekend when it's passed its MOT this week). All going well there should be a free parking space for the next one within a few weeks ;-)
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Re: Wiper motor brushes
rayofleamington wrote:I had a wiper motor pack up today.
----
It works very well - plenty of force and runs the wipers on a dry screen. It used to struggle on a wet screeen, but now we know why.
Oh heck, I wonder if this is on the menu 4 my Mog
1952 Split screen, clap hands wipers. Driver's side works reasonably ok [rubber split soon after replacement] but passenger side hits the outside screen rubber with a clunk [from under the bonnet]. It refuses to park at the same level as it's partner! Garage seemed puzzled after fitting new arms n blades. Said it'll be checked on next visit. Neither will work on a dry screen...
Squiggle
PS Need a workshop manual, must advertise in Wanted section eh?
Hi Squiggle,
If one side of your wipers is ok, then the motor's ok - there's a long mechanical link between the two wiper pinion boxes and the motor.
I'd sugest you change your local garage - what you have is more "slop" in one side than the other. The pukka cure is a new set of pinion boxes, wiper rack, and motor. Most of us turn the rack over 180degrees (re-greasing it at the same time). that can cure most of the problems! Also, make sure the nuts on the wiper spindles are tight (the pinion box is held in place by these).
There have been threads before about "resurrecting" wipers - hav a hunt for the collected wisdom!.
Colin
If one side of your wipers is ok, then the motor's ok - there's a long mechanical link between the two wiper pinion boxes and the motor.
I'd sugest you change your local garage - what you have is more "slop" in one side than the other. The pukka cure is a new set of pinion boxes, wiper rack, and motor. Most of us turn the rack over 180degrees (re-greasing it at the same time). that can cure most of the problems! Also, make sure the nuts on the wiper spindles are tight (the pinion box is held in place by these).
There have been threads before about "resurrecting" wipers - hav a hunt for the collected wisdom!.
Colin
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Thanks Colin,ColinP wrote:Hi Squiggle,
If one side of your wipers is ok, then the motor's ok - there's a long mechanical link between the two wiper pinion boxes and the motor.
I'd sugest you change your local garage - what you have is more "slop" in one side than the other. The pukka cure is a new set of pinion boxes, wiper rack, and motor. Most of us turn the rack over 180degrees (re-greasing it at the same time). that can cure most of the problems! Also, make sure the nuts on the wiper spindles are tight (the pinion box is held in place by these).
There have been threads before about "resurrecting" wipers - hav a hunt for the collected wisdom!.
Colin
Will do as suggested. Next on the agenda is a heater...
Optional extra on the 1952 Series MM's, so staying original.
Squiggle