Is my fuel pump knackered?

[Paul Coleman]

I've just tried to test the fuel pump for my S1. It works and there's a reasonable amount of pressure there but I've been told by others that after a while the pump should stop ticking but mine doesn't. If I leave it with my thumb over the outlet it just keeps pumping away.

 

Does this mean it's knackered? If it is, I'll just buy another it's not cost effective trying to repair it.

 

Thanks, Paul.

[jonwat]

Assuming you're doing this with it pumping fuel, not air, then yes it should stop ticking.

If so, it sounds like there may be a leak in the diaphragm, but they are easily repairable :-)

[Paul Coleman]

Yes I had a pipe connected to the input which was immersed in fuel. I ran it until it started pumping into a container and then put my thumb over the outlet to simulate the carbs being full. I expected it to slow and then stop but it didn't and there was actually quite a bit of pressure behind it as well?

 

Cheers, Paul.

[Paul Coleman]

Okay I've figured out what was going on. One of my makeshift connectors had a bit of an air leak. I found this website with lots of useful info... http://homepages.donobi.net/sufuelpumps/sufuelpumparticles.html

 

After reading this and getting a better understanding of what it should do I've now tested it and it seems to work correctly. So I'll fit it for now and then when it packs up at 11PM on a dark and rainy night in the middle of nowhere I'll think about replacing it

 

Paul.