Pump not chattering

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RedMM
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Pump not chattering

Post by RedMM »

Hi, I'm new to this forum. Trying to get my 63 morris up and running again. The pump sparks at the points but doesn't click and chatter away. The car doesn't start - so pump isn't working. What's my best next step?
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svenedin
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Re: Pump not chattering

Post by svenedin »

The first thing I would do is remove and clean the filter in the base of the pump and check that the metal fuel pipe from the tank is not blocked. Then if that is ok, disconnect the flexible fuel pipe from the carburettor float bowl, put the pipe into a suitable container and try the pump again. If the pump has sat for a long time with stale fuel in it, it can become totally gummed up with a sticky fuel residue which is like varnish. You may be able to rescue the situation by squirting carburettor cleaner in through the pump inlet, with the pump off the car and giving it a good shake. Usually a full strip down is needed.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
philthehill
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Re: Pump not chattering

Post by philthehill »

Your best bet is to replace the pump either from the likes of ESM or even club spares.

panky
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Re: Pump not chattering

Post by panky »

Try a little bit of percussive maintenance, a few sharp taps with a small hammer or other blunt instrument sometimes gets them going.
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myoldjalopy
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Re: Pump not chattering

Post by myoldjalopy »

panky wrote: Wed Jul 16, 2025 6:36 pm Try a little bit of percussive maintenance, a few sharp taps with a small hammer or other blunt instrument sometimes gets them going.
Yes it does, and maybe good for get-you-home in an emergency, but its not a long-term fix. Once it starts playing up, it will continue to do so until it fails completely unless the problem is deal with properly.
I remember years ago driving down through Cornwall on the A30 and having to get out and hit the pump about every mile or two for the last 30 miles. Not fun.
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geoberni
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Re: Pump not chattering

Post by geoberni »

"Percussive maintenance" is for a pump that has been ignored and is overdue a service, it's no use for a pump that has sat for years, and likely dried out and stuck itself together.

It needs a proper overhaul, kits are about £70 including shipping.
If you don't feel able to do that job, buy a serviced/recon one, Club Spares have them.
Basil the 1955 series II

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simmitc
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Re: Pump not chattering

Post by simmitc »

Remove the fuel line from the carb and place in a suitable container. Switch on, does it pump now? Strangely enough, I was working on a Minor this afternoon that started perfectly on 5 year old petrol but then stopped. Float chamber empty. The pump was OK, but the needle valve in the carb was gummed up - it was open initially, then closed as the level was reached. When the float fell again, the needle stayed in place.

Also, the diaphragm in the pump may have gone hard - obvious if cleaned, but some WD40 squirted into the ports and left to soak has been known to work.
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svenedin
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Re: Pump not chattering

Post by svenedin »

It's probably also worth mentioning that if the points are obviously arcing then whatever arc suppression device the pump originally had is either missing or no longer working. Some very old pumps did not have a spark suppressor. Arcing at the points seriously reduces the working life of the contacts. New pumps or refurbished pumps from club spares are fitted with a Transil spark suppressor that greatly reduces arcing. The transil is also included in a full rebuild kit. Also the modern contact breaker assembly is dual contacts rather than the original single contact. If you cannot get the pump to work well with simple remedies it is much better to either rebuild it or replace it because an unreliable pump will just lead to repeated trouble and breakdowns. Keep the old pump as you may wish to rebuild it as a spare at a later date.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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