22 dellorto sticky float?

[a7grenade]

hey chaps; stopped using my 175 top ended 150 series 3 last year when my carb flooded-stripped it down on side of road and got home

used again a week or so later and again it bogged down-fuel pissing out of two overflows

stripped down carb at weekend and cleaned with carb cleaner-blew out jets

ran well-for a bit
did it again and ran out for half hour-parked up-left for half hour-started up and can home

very soon i realised carb was flooding again so kept throttle open to use the fuel up

I'm running a red tipped float needle and the float seems airtight (the needle is hardly used-milage wise)

needle seems to be clear in its hole

wondered what you all thought?

carb oiled up? from fuel/oil mix sitting?
red tip damaged? (looks fine)
float knackered? it is original 60s i think
float pin bent?

thanks

[hullygully]

remove the carb from the manifold with the fuel line intact, remove the float bowl, turn the fuel on & off & have a play with the float, if the fuel stops flowing then detach the float & place it in a container with fuel in, if it sinks then its punctured.

[a7grenade]

Will try that again, I did it once but it looked ok. Might be a tiny hole I guess
Cheers

[northernpete]

Mate had exact same problem and we mentioned it to lads at Scooter Restorations.....they reckon it may be ethanol in fuel causing float bowl to swell up and stick.
He bought a new jetex float bowl and problem seems to be solved...(fingers crossed)

[northernpete]

Just re read original post and noticed you had an original float......ditto my mates.

[a7grenade]

was beginning to think it might be ethanol as it ran fine for a year after rebuild-thanks
will get one

[Scooter Paul]

It was the ethanol, or highly likely. It eats plastic and rubber that isn't ethanol resistant. Ask Ducati they had to recall petrol tanks that were melting.

Paul

[Scooterslag]

Mate had exact same problem and we mentioned it to lads at Scooter Restorations.....they reckon it may be ethanol in fuel causing float bowl to swell up and stick.
He bought a new jetex float bowl and problem seems to be solved...(fingers crossed)

I've had this problem a couple of times- I just put it down to sedative causing the needle to stick, wonder if anyone will make a ethanol resistance float? maybe the new Scootopia 22mm carb will have such a thing? Paul

[northernpete]

Guys at Scooter Restorations reckon the Jetex ones are suitable..........

[Ivor the engine]

Hi,

I carried out a job on a bike and had this as a simialar / exactly the same issue.
I looked at the float, genuine Dellorto. no problems with the balance / weight. I had a spare genuine one from a parts fair and so I tried this as part of an elimination process.
Fitted / replaced the carb completely. Job done. no further gushing petrol from the carb. Although the large fuel sump 'O' ring / gasket looked worn or thin, this wasn't the issue.

On comparison between the two floats, where the float needle engages the float in the ' V ' slot, this appeared to be worn and looked like a ' U ', thus the needle was loose and although not seen when completely replaced, there appeared to be some slop in the needle engaging within the carb due to this wear.

After all this waffle, try a replacement float!

Hope this helps,

Regards,

Ivor.

[a7grenade]

Hi,

I carried out a job on a bike and had this as a simialar / exactly the same issue.
I looked at the float, genuine Dellorto. no problems with the balance / weight. I had a spare genuine one from a parts fair and so I tried this as part of an elimination process.
Fitted / replaced the carb completely. Job done. no further gushing petrol from the carb. Although the large fuel sump 'O' ring / gasket looked worn or thin, this wasn't the issue.

On comparison between the two floats, where the float needle engages the float in the ' V ' slot, this appeared to be worn and looked like a ' U ', thus the needle was loose and although not seen when completely replaced, there appeared to be some slop in the needle engaging within the carb due to this wear.

After all this waffle, try a replacement float!

Hope this helps,

Regards,



Ivor.

now that! makes sense-thanks
I've tried an old one from another carb and it flooded straight away but the needle is loose in both and that would make sense
as the needle is less than 500 miles old (red tipped too) but sloppy would make it sit badly
nobody likes it sloppy
thanks ivor

[maz]

Had similar probs on lots of Jetex carbs........... solved problem by polishing the brass tube that the float needle slides up and down in. I found the best way to polish the tube is to cut one of those ' cotton tipped bud/sticks ' in half and put the none cotton tipped end in a dremmel and dip the cotton tip in brasso before inserting into the brass tube and polishing............ worked a treat on all the carbs I've had probs with.

Maz