Modern Vespa

My lx50 2t started flooding itself on startup and the fuel tap is leaking.

My vespa uses a fuel tap with 2 poles, top for fuel, bottom for air but when looking online for a new part all I'm seeing is this one with what looks like only a fuel line on top and a black ring on the bottom like this

https://www.sip-scootershop.com/en/product/fuel-tap-piaggio_PI575321

What one is right for my model, should I just get one like what I have because I know where the air line goes or not?

I'd also like to change my fuel, air and 2T oil pipes so what size and diameter should I get.

Thanks

That's the tap thats in my bike

Lower down on that page is the one you want:

https://www.sip-scootershop.com/en/product/fuel-tap-rms_14455100

I think the one you're looking at is a manual tap.

Ok thanks

Also the reason I'm changing it is because when starting it'll flood and I have to remove the plug for a few hours and let it dry.

Could the flooding be caused by the fuel tap or something else?

when you pull the fuel line, if fuel comes pouring out then that's a sign that the tap is bad. so that might be part of the problem.

the other part of the problem might be that the needle/seat or the float in the carb is some how compromised.

start with the tap and see how that does.

also, you may need to drop your exhaust and drain it if fuel has accumulated in there.

I tried testing the tap and some fuel came out but then it stopped. This was with the bike off but then when cranking it comes out steadily.
I'm going to disassemble my carb which ice never done before.
I'll give it a clean but what should I do with the float?

That's what I was thinking it was after some research

Thanks

it actually sounds as though the tap is functioning correctly. it should flow only when pulling vacuum. however, if it's original I'd recommend replacement as a matter of course.

visually inspect the float to be sure that it's not compromised: full of fuel, mangled, missing a part or otherwise. then check the needle and seat to be sure there's no trash obstructing it and causing it to hang open. look at the tip of the needle and the seat to check their condition and suitability-- does it look like they seal? it's not all goobered up? from there, check that the float is operating freely and not catching or hanging up anywhere, and that it is set at the factory level (this is in the FSM).

Great thanks

The fuel tap was also replaced about 11 months ago

which tap did you get? there's an updated one that is more complaint with ethanol fuels-- I don't know if that's a worry in your area, but a consideration to take.

anyway, I'd immediately suspect the carb. poke around here and on the 'tube and see if you can find a tutorial. if you get stuck let me know and I'll post up some pics-- I have few kicking around that I can open up.

Hi when I bought the bike it was bogging down and my mechanic put in some old one he had lying around so I'll probably change it coming into spring.
I'm searching on YouTube but extra help from you would be fantastic.
Also any chance that I don't need to replace the float and it just needs cleaning?

Thanks

it's a possibility that it might just need a cleaning.

what kind of carb is it-- brand & size (it should be marked)

Great as far as I know it's a dellorto PHVA 17.5mm

The little black thing comes off and you install the vacuum line.

Thanks

the dell PV 17.5 is a good carb. there's TONS of parts available and there should be a bunch of info out there about it.

that's the carb I run and recommend when doing kits on these.

Great

Tested the fuel tap again and it's definitely broken on open so I got a new one.
Could this be the cause or should I open the carb and check the float or just leave it.

Thanks

likely your problem there.

knock it in and ship it. if there's still a problem then tackle the carb. at least you'll know you eliminated one possibility.

Great thanks

Will this (rich because of too much fuel) cause more blue smoke when riding

only if something (ie a setting or jetting) in the carb is incorrect.

it will smoke like crazy until it burns off all the extra fuel in the motor and exhaust though, so be ready for that.

Ok thanks so much
62 jet because of performance exhaust and malossi double filter sponge, I get a great spark plug colour

Hi,

Found out it wasn't my fuel tap the rebuilt the carb, after sitting up for a week it was still flooded.

Could it be the CDI?

Did your carb rebuild kit include a new needle?

Yes but the original one still looked perfect but changed it anyway

I would pull out the carb again and clean out the needle seat with a cotton bud soaked with alcohol or brake cleaner. Be careful you don't leave any cotton threads in there. There maybe just a spec of dirt or debris on the brass needle seat.

Not familiar with this exact carb, but some floats have a metal tab to adjust the float height. Generally speaking the float should sit even with the edge of the carb bowl when you hold it upside down.

edit: I would avoid any abrasive on the cotton bud like brass polish, toothpaste or baking soda that so many people recommend. Those all just leave smaller bits of grit and debris in the needle seat.

Done all that

Could it be the CDI?

Thanks

CDI has absolutely nothing to do with fuel flow.

Ah ok thanks

I'll check the carb again so

Thanks

I'm going to try the carb again, can you please give me some tips on checking to see if the float is sticking and how to fix it,

Should I press the spring on the needle to see if it's feee?

Thanks so much

I just stripped the carb and cleaned out everything.
I removed the float needle from the seat and cleaned it, but when I put it back in it was much more loose in the seat and would move really easily.
The bike now won't start and just cranks.
My only thoughts on this is that the needle is too loose so it needs to be taken off and put back or the seat part squeezed with a pliers.

If not I'll try the air filter.

Any other thoughts or advice?

Thanks