fuel tap
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fuel tap
Has any one changed the fuel tap on a nc31 super four ??
i want to change it to a non vac one due to mine suffers from fuel starvation some times has any one done this ?????????
i want to change it to a non vac one due to mine suffers from fuel starvation some times has any one done this ?????????

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Re: fuel tap
There was a thread on this site about doing just that about 8 months ago. Try searching for it and you might find it. I presume you will have to buy a gravity feed tap rather than a vacum feed to start with. Then maybe re-arrange the fuel pipes.
Frank
Frank
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Re: fuel tap
Why dont you just remove the plunger on the small diaphram, on the side of the tap you have.
Thats the only thing that cuts the fuel off, when the vac is on it pulls it over to let fuel through.
I have never tried it but I think it would work. If your is no good you cant do any harm trying.

Thats the only thing that cuts the fuel off, when the vac is on it pulls it over to let fuel through.
I have never tried it but I think it would work. If your is no good you cant do any harm trying.

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Re: fuel tap
I had a problem with mine and stripped everything out cleaned everything and put it back together and still the problem recurred so I checked the vent pipes all the rubber overflow and breather pipes were clear.
The actual breather pipe diameter where it goes back into the tank is quite small so I put a small bore pipe onto it and tried to blow back into the tank and found it blocked.
What I did then was to get a length of broken throttle cable and try and push it through, I could not get it past the obstruction so I roughened up the end and as I pushed spun the cable at the same time I could feel it biting on something and it eventually cleared the blockage.
Its been running great ever since
The actual breather pipe diameter where it goes back into the tank is quite small so I put a small bore pipe onto it and tried to blow back into the tank and found it blocked.
What I did then was to get a length of broken throttle cable and try and push it through, I could not get it past the obstruction so I roughened up the end and as I pushed spun the cable at the same time I could feel it biting on something and it eventually cleared the blockage.
Its been running great ever since
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Re: fuel tap
Hi there, the easyest way round the fuel tap is to do the mod on it.....remove tap, remove diaphragm assy, take spring from back of diaphragm & fit it in front of diaphragm (between tap body & diaphragm).reassemble tap & refit. this then holds the tap on all the time so it wont need the vacuum to hold the tap on. you then can do away with the vac pipe from the head to the tap & just put a screw in the head (inlet manifol) to blank it of thus stopping any potential leaks from a vac pipe you wont be useing. Job done. just remember that you now have to phisically operte the tap to turn fuel on/off.
Hope that helps. ( if you understand what i mean).
Hope that helps. ( if you understand what i mean).

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Re: fuel tap
That's what I did.
Damned vacuum operated taps are a PITA.
Damned vacuum operated taps are a PITA.