My coupe coughs and splutters sometimes when on full or partial throttle. I was thinking this was probably dirt in the carb etc. But last night it happened a few times and after stopping and restarting i limped it home where it stopped altogether. I have noticed my fuel gauge isn't very accurate, and sure enough I think I ran out of juice despite the guage showing a bit under a 1/4 of a tank left. As it was dark and getting late i didn't investigate further. I wonder if i'm getting partial fuel delivery when the fuel in the tank is getting low due either to the fuel sloshing around or lack of pressure maybe. I'm pretty sure I haven't noticed it when the tank is reasonably full. Anyone else noticed this? I have a facet type pump and a cheap plastic filter. No pressure regulator. I know I should probably be stripping the carb down and cleaning it all up but am reluctant to as most of the time it runs fine.

Ed

How high is the pump from the bottom of the tank ?

I know some of the facet pumps can't suck very well, they really need to be low down. Look for the "prime height" for your pump

http://www.fuelsystem.co.uk/web-facet.pdf

Also is the tank/cap vented ? Its not a case of building up a vacuum.

Thanks Ken, Don't think my tank cap is vented- would it be obvious? And do you recommend getting a vented one if not?
The pump is situated in the engine bay. There's a steel fuel line that runs under the car and pops out in the back and bends up slightly. The pump is on the end of this so it's probably about the same height as the tank. The pump is a square one and is mounted vertically. I notice from your build pages that you have your pump behind the tank up front. Maybe this would be a better place for it?

Ed

You would know, if you open the cap after a long run, do you hear air being sucked in. I would guess that if you have the standard (MK2 Escort) cap them it will be leaking anyway, so no need to worry.




That could be the cause, these pumps are "pushers" not "pullers" it needs to be as close to the tank as possible.

The square ones are the "solid state" one, so need to be 300mm up from bottom of the tank, max, otherwise they won't prime.

Thanks Ken, I have repositioned the pump up the front next to the fuel tank on the subframe. I have replaced some of the pipes and the filter which did look to be quite clogged. I now have two filters, one just before the pump and the other just before the carb. Anyway after getting a gob full of petrol it was primed and sounding much healthier than it used to. I ran the car briefly to test that the carb is not blocked and she ran very nicely so hopefully it was a case of poorly positioned pump and clogged filter. Oh and I topped the tank up a bit as I'm sure this was a factor aswell.

Ed