A7 ss 1960 500cc single carb

[groily]

An engine full of petrol is not unheard of.

A mate had to do a complete bottom end rebuild when it happened on a Commando without him spotting it  . . . 
He checks more carefully these days before starting off after a period in the shed - and makes a mental note of the fuel level in the tank when parking up.

Glad to say not something that's happened to my notrun SS with chopped Monos yet BS  . . . but am conscious of the risk for the reason you state. A timely reminder as I'm hoping to run her up today after lying fallow since November, and will check.

[BSA500]

Easy check is pull the petrol hoses off the carb and plonk them into a empty jar and see if any fuel leaks past the taps ??

[greeneunos]

Hi took hoses off and the left hand tap has slight leak , also took carb off and a small spacer fell out of the float chamber when I took the end cover off so not sure if it was detached allowing the needle to not close off properly ?
Obviously main cause fuel tap faulty , not sure if the 1/4 turn type are repairable ?

[greeneunos]

Update  , I have stripped the l/h fuel tap , the seal had gone rock hard and actually split into pieces when I tried to remove it , I have read that you have to replace with neoprene seals rather than an ‘o’ ring because of the modern fuel , I want to repair the tap as its original , does anyone know where I might get the seal and a new circlip for the 1/4 turn tap ?
Also I can’t tell if the seal is round or square section as it’s disintegrated as it  came out , I have a spare monoblock carb , it has the original brass float but a plastic needle , whereas the one on the bike had the new plastic Amal float but a brass needle , which would you think I should put back in the carb for the bike ?
Thanks Mike

[limeyrob]

I think its viton you need rather than neoprene but check.  I made this mistake on a fuel tank cap and the seal swole up and locked the cap.  Yours was most likely fitted with this type,: pull with a banjo and acorn nut, but it won't escape you that while the 1/4 turn are £15 these are £ 56! and that's without the acorn nut that's another £8.  I suspect that's why a lot got replaced.
https://draganfly.co.uk/shop/67589/petrol-tap-38x-banjo-1-plung-reserve-only-filter-no-washe/#42-8075petrol-tap-3-8x-banjo-1-plunger-reserve-only-with-filter