Morris Minor Owners Club

My '68 Minor has recently developed a fault; if I'm stuck in a traffic jam for any more than a few minutes the fuel pump starts to tick erratically, speeding up and slowing down as it does (for a couple of seconds) when you turn the ignition on after the car has been standing for a week or so. When this happens the engines starts to idle erratically as well, so I have to keep the revs up to stop it from stalling. Once traffic is moving normally it's fine again.

Any ideas? The only one I had that it was dirt in the float chamber.

the symptoms sound like fuel vapourisation but I struggle to believe that is the actual fault - it's Winter! Brr.

Therefore it is either something that gives similar symptoms or maybe you have a big overheat problem going on.

It would be worth checking the points in the fuel pump - clean them with a bit of card, and check the gap (30 thou').

As Ray says, it's unlikely to be fuel vapourisation, but check the filters are clean (remove & blow through).

(Has anyone ever had problems with the valves in the fual pump?)


Colin

The fuel pump is relatively new - about 2 years old. I don't think it's overheating as it hardly uses any water, and I reversed flushed the radiator and fitted a new thermostat about 3 months ago.

The fuel pump is relatively new - about 2 years old

Ah that's it! Probably well worth cleaning the points!

My car had a new pump fitted as I bought it, after 3 years I had those problems - it seems that the new ones need a bit more tlc (try cleaning annually - just a bit of card between the points, or new points if needed).

NOW I keep a spare set of fuel pump points in the car.


Colin

Thanks Colin, I'll try that at the weekend.

Most likely the little float valve in the carb is leaking slightly - when you are driving the engine uses enough fuel to make it not matter - but when stopped the carb is 'flooding' - hence the poor running. So I suggest a new float valve asap !

Most likely the little float valve in the carb is leaking slightly - when you are driving the engine uses enough fuel to make it not matter

not a bad idea - it would also fit that it only happens when warm, as the engine would complain more about the extra petrol

I've got a feeling the carb might need a good clean out and rebuild anyway, so I might just get a kit from Burlen. Anyone know if a float valve comes with the rebuild kit?

Ask Burlen - but I would leave well alone and just get a new float valve. Not much to be gained by fiddling with the carb - unless you are going to 'Vizardise' it.

Fuel pumps - Arrgghh.
Mine drove me scatty, it cut out in the most awkward places and wouldn't start until it was ready. I cursed it, I cleaned it, I thrashed it, all to no avail. I bought another one in the end. When I can bear to look at the old one again I'll take it apart and try and rebuild it for a spare.
If I think of it too much I'll be back on the tablets