fuel tap/flooding problem

[PSNOWDONPAUL3]

hi people.recently joined the forum,so sorry if this thread already exists.ive been doing a restoration/refurb on a 1991 nc30.all body work mods are done and have come to start the bike today before new fairing goes on.theres a new battery,plugs and leads on.ive checked the reg/rec following haynes manual instructions.ive got good sparks and fresh fuel.the tank was swilled out 3 times before final filling.

on starting it just floods.ive checked theres a vacuum from the vacuum pipe and it sucks like a good en.i took the tank off,opened the fuel tap and petrol pissed out.i know that this should only happen if theres a vacuum applied to the pipe.so i stripped the fuel tap down and checked the diaphram for damage.its fine,with no rips or fouling.

to cut a long story short-i put it back on the tank,and when put on the on position it didnt leak fuel-as it shoulnt.back on the bike,after whipping plugs out and drying them.turned it over-nothing but the strong smell of fuel.stripped tap down again,and strectched the spring,built it up and had a friend suck on the vacuum connection,while i sucked on the fule out connection.when he stopped,the fuel out stopped-hey presto!!

last bit-sorry!

tried it again-nothing.so yet again stripped it but built up half of the tap,sucked on the vacuum connection and the diaphram moved,then returned v e r y s l o w l y.think that it is stopping fuel,but is letting too much in as it shuts? any ideas very welcome !!

[temeluchus]

You will have to have the carbs off and get the float bowls off.

Check the condition of the float needles, in particular the tips. If they have a worn step in them they will need to be replaced. The tips should be smooth with no obvious wear or shouldering.

Also check the condition of the floats and their adjustment. Do they float in some petrol, do they move freely?
____________________
Some shite cruiser. Now with guns and FREEDOM!

[PSNOWDONPAUL3]

cheers for that.should of mentioned-ive done no engine work and the bike started alright before i started cosmetically messing,about a month ago.i have got a new tap on the way just incase it is a sticking daiphram.

[Vincent]

[PSNOWDONPAUL3]

prime position? oh dear..........

[Vincent]

[PSNOWDONPAUL3]

hi guys.just a quick update......am now ready to sell this as a work in progress!! checked floats and carbs today,fitted new tap which works perfectly and checked sparks.had air box off,squirted easy start into carbs,and it "fires" but wont hold its own.so f*****g annoyed with it!!

any ideas please? ive said that if its not running by mid week its going-as its kept at my work its beginning to get in the way

[Vincent]

You could get yerself onto the 400greybike forum. What those guys don't know about VFRs isn't worth knowing. Careful tho, they don't suffer fools gladly and take no prisoners.

https://www.400greybike.com/

My first thought might be that the carbs are at fault, esp if the bikes been standing. Blocked pilot jets perhaps? Try starting it with no throttle and see if the plugs get wet.

[PSNOWDONPAUL3]

cheers for that vincent.im working tommorow so ill have a look.its got to the point that im nearly out of patience with it!

[Vincent]