Classic cars forum & vehicle restoration.

FAB Cruiser · Joined: 03 Jul 2008 Posts: 77

Hi,

I’m converting a 1966 MGB to negative earth following the instructions in a kit from Moss.

It says that if the car has a later SU pump (as mine does) this should be converted by reversing the diode under the cap.

Having taken the pump out, there is no diode under the cap.

My pump is an SU model AZX 1307 with points. SU list it as ‘dual polarity’ as opposed to the electronic versions (e.g. AZX 1307EP and AZX 1307EN) which are polarity specific.

On this basis, can I just leave the wiring connected to the existing terminals, and all will be fine?

Many thanks
David

ukdave2002 · Joined: 23 Nov 2007 Posts: 4105 Location: South Cheshire

yes

Diodes and capacitors were fitted across the points to reduce electrical noise and reduce points wear. but the don't affect the workings of the pump. The pump its self is not polarity sensitive

Dave

peter scott · Joined: 18 Dec 2007 Posts: 7119 Location: Edinburgh

Hi David,

Yes, the only thing you will need to alter apart from the battery terminals is the ammeter connections.

Peter
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

MVPeters · Joined: 28 Aug 2008 Posts: 822 Location: Northern MA, USA

& the coil connections - it will sort of work reversed, but not very well.
& check the clock & radio, if any.
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Mike - MVPeters at comcast.net
2002 MINI Cooper 'S'

FAB Cruiser · Joined: 03 Jul 2008 Posts: 77

Thanks guys, I've completed all the other conversions which included dynamo to alternator, coil and tachometer. I just want to ensure I'm not going to fry the fuel pump or make it run in reverse.