Facet Fuel Pump, Plus Other Fuelling Question!

[m.i-man 0]

I bought all my carb bits second hand. How would I go about testing that the fuel pump is working? Do I just connect it to a battery, and see if it spins? Also as there were no instructions for the pump, when you install it in the fuel lines, do you have to somehow prime the pump first? Or will it just draw the fuel through on it's own accord?

 

After reading the carb conversion article on the main page, I'm a little bit stumped of where to put the 8mm copper tube? Does it rest in the actual tank, or inthe blue pick up where the baffle part is for the original pick-up pump?

 

Basically I don't want to carry on and do something completly stupid and cock something up and risk damaging parts, or the general result of the conversion!

 

Cheers guys.

[Guest CB-Dave]

the last time I did anything on a carb conversion on a gti, we took the fuel pump out of the tank, took the pump itself out of it's carrier and jammed the 8mm copper pipe from the top of the carrier (where the fuel lines connect to) out of the bottom of it, so it was sititng in the bottom of the tank.

 

If you don't do this, then it will idle when you first start it up with the carbs on (provided the pump is disconnected) but as soon as you move it'll misfire and generally run crap cos it can't suck the fuel through the pump (as it's not operating)

 

As for the facet, easiest way to test if it's working is to plumb a couple of lines to it, get a coffee jar full of petrol and an empty one, slap 12v on the pump (far away from the petrol, natch!) and see what happens, if it blows bubbles in the petrol the pump is the wrong way round, if it transfers the petrol from one jar to the other then it's all good...

 

the solid-state facet pump we used on the conversion I helped out on primed itself, as long as there was fuel to suck up it would suck it to the pump and cut out

[m.i-man 0]

Sorry I didn't mean drawing the fuel through the old pump. I meant where the old lift pump located is like a baffle, I guess to stop fuel surging away from it during corners etc.... Does the copper pipe feed from this part, or literally just anywhere in the tank?

 

Also you say the fuel pump will cut out? Why does it do that when fuel gets to it?

 

Cheers.

[Guest CB-Dave]

I duno why it cuts out when it's primed, just remember the one we had did

 

As for the baffle - yeah, keep that submerged in the tank, and put the copper pipe from the top of the pump carrier into the baffle (which will be immersed in petrol anyway)

 

I guess once the engine is running, the fuel pressure is lower so the pump will activate - bearing in mind, this was a rallycross car and as such had fuel cut-off switches and everything all over the shop!

[m.i-man 0]

Right, cheers for that mate. I checked it last night and I don't think the pump works!! So i've put an in-line t-piece for the fuel return and the FPR to run from the original lift up pump.

 

So have fuel working now, just got to sort out a spark tonight!!

Think the coil is suss, or suppose it could be the dizzy.