Morris Minor Owners Club

When the polarity is reversed - the points should be filed flat again before use on the 'new' polarity.

bmcecosse wrote:Don't think so - they seem to be sold for specific earth arrangement - but you could ask the supplier - there may be an internal switch. The general opinion on here is that electronic SU pumps are to be avoided like the plague! Far more reliable with a good old pump fitted with new points.

burlen fuel systems will sell you for 38 pounds a new board to swap over the polarity.. my dad has been using an electronic one on his MO for three years now no problems.. it does very little mileage ( no idea if that is good or bad for pumps? )

charlie_morris_minor wrote:it does very little mileage ( no idea if that is good or bad for pumps? )

Probably doesn't matter with an electronic one. With points, regular usage is good to prevent oxide building up on the contact faces.

Heres a can of worms! Just wondered, whats the advantage of negative earth and alternators. My Pickup is still positive earth with the dynamo.

I have got a pair of high power demanding 7" Lucas SLR700 driving spot lamps on the front bumper and the pickup doesnt get started for most of the year and "touch wood" Ive never had any battery issues to even think about an upgrade to an alternator.

Ok I know my dynamo doesnt charge at engine tick over speeds but I use the glowing ign warning light to set my tickover speed.

Steve B

Mine is neg earth and dynamo and spotlamps but still never had an issue starting.... Got the crank handle if I do though

I suspect your p/up is only used in summer ? And so - the lights will rarely be used ? Even so - I used to do all-night rallies - with 2 of these extra spotlamps (they are hardly 'high power'!) and a dynamo - never had any real issues - but obviously I doused the lights when ever not needed to allow the battery to be kept up.