Fuel starvation(float needle+valve)?

[ove]

Hello all need some help if possible. I have a fuel starvation issue, It`s a 28PHBH carb and a fast flow fuel tap. I checked the flow rate just through the tap and fuel pipe, and I`m getting approx 450mls per minute. I take the main jet bolt out of the bowl and test it again, 300mls per minute!! Take bowl,float assembly and needle out leaving valve in and re test approx 450mls per minute. Thinking may be float is sticking on bowl so I assemble it float and needle so nothing is obstructing it and its open, 300mls per minute.
The float valve is a 350(largest I have) Needle is green tipped, is there any point in trying a larger size or drilling out a 250? Or faster flow fuel tap??

Any suggestions on helping my fuel flow problem would be most welcome.

cheers ove.

[tonydevon]

450ml a minute, doesnt sound a lot, sure mine was lot faster, will try and find the info in my notebook

didnt take long

1 pint in 38 seconds. 1 litre in 1 minute 13 seconds

[eden]

Ive been having the same issue with starvation at sustained high RPM so yesterday I dug this out of the garage and fitted it, when its turned on it flows 30% more fuel through the float valve than when its turned off. It still flows when the pump is off via the bypass pipe which is also there so the fuel can circulate when the pump is on and the float valve is closed. Ive wired it to the lights so the pump is only running when the lights are on for testing purposes to see if it cures the problem.
The pipes are so long because I want to be able to put the fuel pipe back on to the carb if the pump fucks up which it may do because I broke the exit part of the pump and had to glue a narrow copper tube in to the hole to connect the petrol pipe to
Its a bodge and looks shite but I'll find out if it works on the way to Cobblesoul this weekend, if it doesn't its only cable tied on so it wont take long to take it off and f@@k it over the nearest hedge.

[tonydevon]

love it

[ove]

Fookin hell Eden, that might be beyond my capability but nice work fella.

[Mr G in NYC]

Whoa ! the way things are going looks like these lambretta's
are gonna be running EFI systems soon…….that pic looks like
something from the Russians first outing into space 'Sputnick 1"
Nice job G. and let us know if worked

[eden]

be interesting if the fuel line gets dragged round the back wheel

[fastfrog]

don't forget to fit a "smaller" 200 float needle if a bigger one was in place before.

[eden]

no need because ill only be using the pump when im running over 7500 rpm.
if I find im riding in the dark before ive had time to add a switch I will just take the live connection off the lighting circuit.

[fastfrog]

ok capito... Nice tweak....