Yes we have done it on one of my 401 project cars as a dry run for doing it on my other 401 which is back on the road,that car had been equipped with positive earth led bulbs so we needed to retain the positive earth set up on the subject car, first thoughts went towards the later two speed positive earth wipers used in the later Bristols and others but the snag is none of them have the required angle of sweep in their gear wheels which according to the Lucas chart for the motor is 95 degrees. A fellow 401 owner said they had done their conversion with a two speed negative earth motor acquired from Stafford Vehicle Components but they had changed the rack as well which I didn't want to do, a quick call to SVC confirmed that the motor they supply has an insulated case so it can be run in the correct direction of rotation by wiring it directly to the battery via its control switch.
I decided to give it a go and ordered the following componants,
Lucas 14w 2 speed wiper motor ref SVC-LULRW1101,
14W Wiper drive gear 95 degree ref SVC-LULRW110,
Lucas flick switch 2 speed wiper ref SVC-LU35927,
14W Wiper motor mounting pad ref SVC-54701831,
14W wiper motor mounting strap ref SVC54701783,
Wiper motor connecting kit ref SVC-WMK,
There is a wiring diagram on the SVC site and and one of the MGA forums showing how to wire this up, needs slightly revising if you have and are retaining the car as positive earth.
One thing that this motor has in common with the later positive earth motors is that the recess in the casing to retain the outer sleeve of the wiper rack is larger than the original motor, so you will need to devise a simple clamp to make sure it is secure to the motor.
The other factor is that the motor is physically bigger than the original and has a different mounting method, an insulated strap.
If your car is like mine with the wiper motor on the left hand side below the dash there is just enough room to fit it in place.
We removed the old motor and its mount and made a mounting plate to fit the original bracket, determined the best angle for the motor and drilled the mounting plate to accept the new mounting strap.
The motor has two live feeds as one is needed for the park function. It occurred to me that as we were no longer going through a circuit controlled by the ignition key one of these feeds at the motor( and the switch ) would still be live with the control switch in the off position. This was easy to overcome as we used the existing single speed wiper switch as an isolating switch.
The whole set up seems to work well the only thing we noticed that it parks the wiper blades next to the centre pillar of the screen. Have not asked SVC if that can be adjusted but it is no problem because with the isolator set up I can stop it anywhere I want to.
By the way if your old rack needs replacing I am told that one of the early morris minor racks is a direct, or almost replacement, if I can find the suppliers name I will add it to this reply.
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