One of the last steps in my dual weber project is finding out how to mount and wire in the fuel pump. The previous engine had a mechanical fuel pump so I don't have any old fuelpump wires I can repurpose. I've got a big white/pink wire that used to go to the manifold heater. I've read that I can use this circuit for the fuel pump too. So if that is correct, what is the best course of action? - Should I mount a fuelpump against the firewall so I can use the pink/white wire? - OR should I place one closer to the fuel tank and pull a new wire? - What kind of fuel pump is best suitable? Hope to hear, thanks in advance!
What's the car? The pumps definitely push better than they pull, I always put the pump as close as possible to the tank. Like where VW put the high pressure pump on a GTI. If you get some of the original gti loom, you'll be able to wire it in as per factory.
As Tristan says, I think you will struggle with the fuel pump in the engine bay. I also think you will struggle without the pump in the fuel tank because the fuel has to come up and out the top of the tank. Without the lift pump to help you may suffer with air locks or "priming". To me the the VW design of fuel coming out of the top of the tank is weird. I am happy to be corrected here of course and I’m sure someone more knowledgeable will be along soon.
I've done it with the pump sucking from the original pickup, with the put mounted where VW fit the injection pump, with no problem.
Thanks for the replies guys! Car is a mk1 convertible. The original engine was I believe a 1.6 RE engine. So I don’t have a pickup in the tank or otherwise. What I’ve seen on other forums and posts is a pump located under the car near the tank. Just in front of the rear wheel. But then I’m wondering how to get the wires there. So you guys also recommend getting an intank pump? I suppose I can salvage any version from injected models?
That's how vw do it on the gti, fitting it there. Run the wires under the carpet and out through a Grommet is the easiest way. And tap into the existing fuel supply to the engine mounted pump.
It's much less likely to leak if the lifter/ pump assy is in the top of the tank. Nearly all the plastic fuel tank bike and cars I've worked on have the sender in the top (only one that springs to mind otherwise is RSV Mille).
the old heater wire is a good one as its fed by the big spade 'N' on the fusebox which is powered by the fuel pump relay on a gti, so all you do is fit a non-rev limiter type mk1/2 kjet 8v fuel relay and you're all set. put a fuse inline though. as above probably want it at the back though, so locate the wire at the fusebox, cut it to insert inline fuse then run the output to the rear as desired
or if you feel up to the challenge source a pin for E/14 fuel pump power on the fusebox, then you can use the factory GTI fuel pump fuse on the fusebox. the terminal is a 'mate-n-lok' and suppliers such as polevolt.co.uk can supply. or dig one out of a donor loom. https://clubgti.com/forums/index.php?threads/fusebox-faq.219775/
