The fuel pump on my 87 2cv appears a little weak. When left for a couple of days, the fuel is seemingly draining back through the pump, and then needs to be primed before it'll restart. Also, whilst idling there is only a small trickle of fuel through the pipe.

Is this a sign of impending fuel pump failure?

Thanks, Ben

Sounds like classic symptoms, Ben. I haven't checked the 2CV's output, but on every other mechanically-fuel-pumped car I've owned, the output is very obvious 'squirty-pulses' even when cranked slowly. 'Trickle' doesn't really apply.

I take it the hoses look ok - no obvious leaks - and the pump itself is securely mounted?

Worth looking at this thread too:

viewtopic.php?f=7&t=1881

If you decide to replace it, get the correct one!

At tickover, there's so little demand for fuel that the fuel pump 'idles', with only the required trickle of fuel passing into the carburettor bowl.

If you test the fuel pump with the hose disconnected from the carb, that's a different game altogether...

ken

Check the pipe where it exits from the tank.
One of our local group members at this years registers day thought he'd got a fubar'd fuel pump.
It turned out the rubber pipe had split.
It needs the tank dropping to check ....but at around £25 for a new pump .....


Edit .....my pump "died" a couple of years ago,the first symptoms were a misfire when cornering enthusiastically ....I put it down to the pump delivering so little fuel that it was "sloshing" around in the float bowl,and thus causing fuel starvation symptoms.

T.

Hi Ken. I'm assuming he is testing the flow with the fuel pipe disconnected from the carb.

Yes, worth checking the flexible hose from the tank. Just thinking aloud - can this be given a perfunctory check by gently blowing down the fuel line - say where the rubber hose from the pump inlet connects with the main fuel pipe, and with someone holding their palm over the filler neck to block it, and a third person under the car listening for...

Ok, just drop the tank...

(And Waxoyl under there while you're at it )

Yup .....and clean/replace the earthing wire/connections from the fuel guage while youre at it ....

DA,
Terry may not be aware of the fact that I suggested blowing into the filler pipe of that car which had conked out at Registers' Day, but was overruled by someone already wielding spanners to remove the pump.

It was only after a new fuel pump had been purchased and installed, without any success, that the aforementioned 'kiss of unleaded' was carried out...

No need for anyone to listen, as petrol flowing onto the ground underneath the tank was probably enough evidence...

ken

I missed out on that bit Ken .... I was too busy draining 25 litres of deisel outa my own 2CV ....
That Farmer must now have the Fastest Fergie in Fenland ... ....[he got 25 litres of 80/20% diesel/petrol mix ......for free.]

For the benefit of anyone who missed out on the episode ...
I rather stupidly put 20 litres of deisel into my 2CV .....surprisngly,it made it the 2.6 [satnavved] miles to the campsite,running on 80% diesel fuel.
Upon which,realising what I'd done .....I drained the fuel outa my car [thank heavens for "in line" fuel filters in the front wheel-arch].
Mike Johnson then took me back to the garage for a gallon of petrol .... [Nahhh ....2CV's dont run too well on weasel juice] .....And on the way back Mikes car died as a result of a leaky fuel pipe..... [Which resulted in in us having to call one of the RADARS ....(Rotherham And District Assocition Of Roaming Snails) .....to tow us back with his C5]

Anyway .....Mikes fuel pipe got sorted [after he'd bought a new pump ....and found it was a leaky pipe ] .....and after three hours "draining" my tank was clear of deisel.
And my 2CV was non the worse for a "deiseling" .....

T.

>hrumph<

missed all the fun

yet again the fuel pump takes the blame
Ben if its a pump that can come apart take it out and dismantle , clean the non return valves with a squirt of carb cleaner and see how it goes...youve nothing to loose

often its crusty deposits from drying out and crud thats made it thru the filter in the tank that cused the valves to play up, the actual pump seems to go on for ever( with notable exceptions)

Hi Ken. Let's see now, what's easier: one person blowing through a disconnected fuel line low down on the filthy chassis rail with two other assistants - one sealing the filler pipe and t'other on ground listening for leaks - or, er, um, *cough*, doing what you suggest...

I dunno - I think I've got myself into the 2CV frame of mind, where every job just has to be an awkward bu@@er.