Modern PS pump on neg earth car-will it work?

[DanCat]

Hi,
I'm intending to use a modern electric power steering pump on my DB6 as a friend has done to replace to engine driven pump. This is a far cheaper alternative to locating the origional pump that i don't have with the additional benefit of being able to switch it off on the motorway.
My friend has already converted his, however his car is +ve earth.
Will the modern pump work on a -ve earth car?
Will it work backwards?
Will it catch fire!!!!!!???
All thought, particularly those of an auto electrician(!) greatfuly recieved
Dan

[stevieturbo]

Unless you have a pressure accumulator of some sort...why would you want to switch it off ?

Steering assistance needs to be ready to go, at any instant regardless of road type.


And why would chassis polarity matter ? Isolate the pump and run 2 wires to it.

[wildoliver]

Is the car pos earth or neg earth?

Modern cars are neg earth. Therefore so is the pump.

[annodomini2]

All modern cars are negative earth as has been said.

If the pump has the ground connection on the connector there shouldn't be a problem with it.

The issue with a +ve earth system is you would have to isolate the housing of the pump unit from the chassis or it may power down.

The main issue you will face is getting the unit re-tuned to suit your car.