Fuel Pump Info

[blandy 29]

Bit of a strange one this but after a bit of reassurance to my logic.

 

I've a question over the health of my fuel pump. I've recently gone to fit a smaller alloy tank. My original tank was 3/4 full so thought I'd cheat as didn't have a suitable tray to drain the tank into so disconnected the rail fitting abc put 12v to the pump to remove the majority of fuel.

 

Now In doing so worked well for the first 20litre and then the pump slowed and virtually stopped and became irratic.

 

In my mind when the cars running the fuel pump would be running non stop like the above so in theory would suggest my pump is a prob on the way out?

 

It did cross my mind that in normal operating conditions there would be return fuel comming back which is fed on top of the pump which could cool the pump (not sure if it does cool) but if that's the case my new tank with 2x pumps is set up that one feeds the fuel into a centre chamber/baffle that is then fed to the rail with another pump to combat surge and the return goes into the centre so the standard pump again would be like my test above just sat pumping all the time with no fuel returning to the top of the pump

[welshpug 1,657]

the pump will always be submerged in fuel even if there's no fuel returning (there will be unless you can draw more fuel into the engine than the pump can pump)

 

 

how old is your pump and did you still have a good 12v+ going to it?

[blandy 29]

Yeah had a good 12v. Age wise who knows could be original (is definitely original type) so definitely wouldn't be unreasonable to be old and tired. I had a few fuel "surge" issues well what I thought was surge but may well just have been the pump struggling.

 

Just wondering as have another 2nd hand unit in my new tank as well as a new walbro unit so want to test it before fitting the tank - it sits in standard location but pumps are not accessible through the original access holes

[petert 586]

When empyting the tank, the pump will out flow the tray that the pump sits in. There is only a single 3-4mm hole in the tray. Thus it is time consuming to remove the last 15 or so litres quickly.

Edited January 2, 2017 by petert