Wiper motor on 12 v?

[bobthompson]

I want to run a 6 v Lucas DW3 wiper motor on a 12v negative earth car. Can anybody advise what type of stepdown gizmo I need to achieve this?

[Tony Griffiths]

There are many compact "made-in-China-buy-at-your-own-risk" units on eBay: https://www.ebay.co.uk/itm/333863355574?...SwaIRZss1X
I have a 6-volt to 12-volt unit to run the indiactors. I keep a spare in the glove box.....

[bobthompson]

That one states 3 Amps at 6 volts. Do you know how many Amps a DW3 is rated at anybody?

[Bill Dixon]

I would look out for a 12volt motor,then sell the 6volt unit. There are more 12v units about than 6v ones. These cheap units from China can be of poor quality.

[andrew34ruby]

My 6 volt wiper motor runs fine on 12 volt, but it does get a bit hot. I have purchased, but not yet fitted, a resistor to go in series with the wiper motor, 25 watt 2.2 ohms.

https://www.ebay.co.uk/itm/122180980450

[Dave Wortley]

My 6v "pull and spin" motor has run on 12v since 2003 without any problem. But it doesn't always rain when I go out in the car.

[Tony Griffiths]

David, on 12 volts, does it wack around faster than on 6? I connected ours to the fuse box and it worked OK, but direct to the battery and it was a good deal better So, that's where it is, on its own fused circuit. Another member of the Sheffield group has his arranged in the same way.

[Dave Wortley]

Hi Tony, I haven't tried the Ruby type motor on 12v but suspect it would not be as robust as the "pull and spin" type. Perhaps it would be better with a resistor in the circuit. Someone on here will be able to give a resistor value.
Cheers,
Dave.

[Bob Culver]

For a heavy current device resistors are not ideal. To lose 6v at 3 amps is 18 watts; equivant one original headlamp!
I trust everyone  at least owns one of the very cheapest analogue meters suitable for old car use (esp if  not adjusting any voltage regulators) To lose 6v at 3 amps is just 2 ohms, but the loss peaks with current so tends to drop volts at the part of the sweep where most needed, accentuating the speed variation. 18w or even 10 gets hot..

[Tony Griffiths]

Hi Tony, I haven't tried the Ruby type motor on 12v but suspect it would not be as robust as the "pull and spin" type. Perhaps it would be better with a resistor in the circuit. Someone on here will be able to give a resistor value.
Cheers,
Dave.

Our Ruby has a pull and spin type - it was on the car in 1970 -  and I believe it to be original; am I correct? BTW, the later wiper that's fittedon the '29 Chummy works very well indeed.