Morris Minor Owners Club

hi there.

the guy before me hit the petrol pump with a birmingham spanner and got it to work when he demoed the car.

it's always started up real quickly and on the button but today i cranked her after the winter in the garage and the petrol pump doesn't seem to be pumping juice on starting. she was looking low on petrol. i went for some emergency petrol can and filled her up and tried again, is the petrol pump self priming? can i run a bit of wire from the positive to the pump, clean the tiny contacts inside with a nail file and see if that works? otherwise, how much is a new petrol pump for a morris minor '68 series 2?

cheers!

xpress

how do i wire up a pump to a car battery to check if it ticks? is it just the positive terminal used or does the pump need to be earthed? i can only see one electrical wire (+?) going to the thread.

It should 'tick' whenever you switch on the ignition. Good idea to clean the points - but do it with the Ign OFF!

Switch off the ignition and disconnect the wire from the end of the petrol pump. Disconnect the fuel line from the carb. float chamber and place the end in a jar.
Switch on the ignition then touch the wire back onto the terminal on the fuel pump which should tick rapidly and pump fuel into the jar. If it does not pump then switch the indicators or wipers on. If they do not work either then check the fuse, if they do work then the pump needs servicing or replacing.

does it tick once or repeatedly? that wire going to the pump is that positive terminal 12v, i can't see where the negative earth goes, is it just earthed by being connected to the chassis? please advise. how can i test if it ticks out of the car with a car battery? thank you for your replies.

i was going to try and clean all the contacts with a magnifying glass and a nail file, i might even try a bit more birminham spanner and wack it a few times! maybe i should have clunked it a bit harder before taking it off the car! i have a spare one that i am trying to test as well that looks in better shape.

i put the car back in the garage without blocking the fuel line will it be ok, it can't vapourise in a day can it?

i came back to the car after six months and it went from a third of a tank to nearly all gone! how quick can half a tank vapourise, or is this also for safety?

It can certainly 'vapourise' - but are you sure the tank isn't slightly porous - and it's been leaking through ? Check to see if it's 'wet' with petrol underneath. Just connect the pump terminal to a battery - and earth the body of the pump to the other battery terminal. When running 'empty' - it should tick steadily - it onlt stops ticking when back pressure from the carb inlet valve, holds the points on the pump open.

Hi,

I've just fitted new points in my SU pumps...

The following page is essential (didin't see it until I had 2 pumps not working)..
http://www.sucarb.co.uk/TechnicalDetail.aspx?id=49


Now I have 2 working pumps, you're welcome to make an offer(?)

Alos, there is (on all of mine) an earthing wire from the contacts to a small screw on the body (the bottom - largest diameter), from there to a ring that fits over one mounting bolt.

HTH

Colin

well this is a good point. i realise that clunking the pump isn't really a long term fix, also .. if there's no earthing wire, it's relying on the contacts of the pump to the mounts on the engine bay, and if they are not good clean metal that might affect the connection? i will get some wire and test the pumps with an old car battery. thank you for the offer of a pump i might have to sort something out with you if these ones need cleaning up and overhauling, might get me going quicker. seems like a good idea to have a spare pump in the boot in case of emergencies!

i cleaned the points up a bit and got the pump ticking again but the mechanism seems to take a while to release back, on the battery whilst testing it's not ticking as fast as i thought it would, should it tick a few times a second?

hmm. how many times a second is the petrol pump supposed to tick when the 1st position ignition is put on and also when starting? i don't think it's ticking fast enough maybe once every couple seconds, and is that enough to pump the fuel up?

also, how long should i be able to crank the car andn try to start it with a good charged battery? i am getting a couple minutes and it's going dead again.

The pump will tick quickly at first when you turn ign on then settle to about once every 10secs - same when running. You battery sounds like it is going flat too quickly so probably needs replacing.

is quickly like once every 1 second or 2 seconds when first turned on?

Depends on how long since you last cranked. If a day then you would get rapid fire ticking... If only an hour then not much priming required....

You shouldn't need to crank the engine for two minutes to start it - 3 to 5 seconds should be enough! No wonder the battery goes flat. And yes - the pump just ticks as fuel is used up. Look to reasons why it's not starting - plugs/points/condenser etc etc.. Make sure the choke control is working as it should.

is it just earthed by being connected to the chassis? yes just make sure the bolts are tight and the area is free of oil and rust

Hi,

if the pump is "no load" (i.e. no fuel line connected) - it will actually hum!

That's lots of ticks/second. The rate of the tick (when in use) depends on how much fuel is used up. The float valve in the carburetter detenims how much fuel comes from the pump - when the pump reaches the end of it's stroke it should make contact and re-fill.

First thing in the morning, the pump will tick once or twice when I turn on the ignition, then stop until the engine has started...

Colin

cheers colin. i am not getting that amount of ticks per second when i connect the pump up to the battery, a slow tick then a slow retrieve of the pump and another tick .. and so on. maybe time for a new pump because i think the diaphragm is looking a bit snail like too. although it is ticking so i might work out this no spark problem first. going to check the resistance of the coil now.

i realise that clunking the pump isn't really a long term fix

Years ago people avoided having frequently to lift the bonnet and hit the pump with a spanner by using a large nut and a piece of string.

Tie one end of the string to the nut and the other end to somewhere underneath the bonnet so that as you drive along the nut swings about underneath the bonnet and as it does so hits the body of the petrol pump. Problem solved!

lol! i could always train a little bird to sit in there and tap it with its beak as i drive along!

The pump will be fine - worry about the sparks!!

i am worrying about the sparks ...