Intermittent Windscreen wiper fault

[Nimrod]

Not sure whether this is mechanical or electrical, so I'm posting to both!
The wipers switch on OK but at random intervals they stop at whatever position they are in, and again at random intervals, start up.
Is there any way I can do a definitive test to find out whether this is an electrical or mechanical (ie motor) problem, without getting another motor? (Expensive!)

thanks

[bmcecosse]

Check all the electrical connections first. And when running - are they going at normal speed - or 'struggling' ? Could be brushes - not expensive and easy to replace.

[Nimrod]

Check all the electrical connections first. And when running - are they going at normal speed - or 'struggling' ? Could be brushes - not expensive and easy to replace.

normal speed.........

[Kevin]

The other problem that can occur is that the grease used in the original fitting becomes very thick with age and can gum things up a bit, taking it apart and then removing the old grease and replacing it will often improve things, also the gears can wear and by turning them 180% you get an unworn section of the gears and dont forget to mark the motor covers position as this affect the parking position.
It just sounds like yours needs a good old fashioned overhaul.

[paulhumphries]

Some wipers have a switch that cuts off power for the self park facility.
On later Lucas units it's a small white box on outside of motor.
If your's is different then there will be some other switch for the self park.
Maybe worth also checking that isn't faulty / sticking ?

Paul Humphries

[bmcecosse]

If it's normal speed - then seems more likely to be loose electrical contact - or brushes. Next time they stop (and it's never going to be somewhere convenient) worth checking if power getting to the motor - and if wiggling the connections makes it go again. If it goes when you give it a 'dunt' - then suspect the brushes.

[minor_hickup]

If its any help my wipers did the same, just stopped and I got them going but they kept doing it. It was the pin on the gear wheel inside the wiper gearbox taht was at fault. It had no lubricant and was seizing up.

[Nimrod]

It was the pin on the gear wheel inside the wiper gearbox taht was at fault. It had no lubricant and was seizing up.

Is there a lube point for this? (I don't have a manual at the moment....)

[Willie]

Nimrod, the wiper motor is 'live' at all times when the ignition is on(Green wire)and when you switch the wipers on you supply an earth via the 'E'
terminal on the Control Box. This earth is via the Black lead which you will
find about 7" below the fuse box behind the vertical wiring loom on the bulkhead where it is clamped under a bolt head which often makes a bad
connection due to rust. Worth a look. A similar fault I had on one of my Minors was due to the fact that one of the clamp nuts on one of the wheel
boxes had worked loose which allowed the outer cable to jam on the inner and lock up whenever it felt like it! Difficult to get to though.

[minor_hickup]

Nimrod, there is no grease point, simply remove the lid from the wiper gearbox and take the arm off the pin and grease it. Probably worth removing the horrible old gummy grease and replacing it with new.

[Kevin]

simply remove the lid from the wiper gearbox

Whatever you do dont forget to mark its position or you may have sweep problems.