HS2 Float Chamber "Leaking" from the Bottom ?

[Polarsilver]

Fired up the 1275GT today first time this 1300GT engine has run for 1 year .. prior startup I pumped out the tank & sucked out the HS2 Chambers then filled with 5 ltr of fresh fuel & Engine fired up without issues quite pleased .. until checking under the Bonnet to see Petrol heavy leaking out from the "underside" of one float chamber this fuel leak is engine running or stopped & when leaving the ign on to get the pump supply .. with a Mirror i could see petrol emitting from where the Jet supply pipe joins into the underside of the Float Chamber .. took off the Carbs to get access & then tighten the Hex Nut securing the pipe into the float chamber it took 4x Flats to tighten up .. so refitted carbs & with Pump On this dripping fuel leak has stopped... for safety i will take the carbs off again & give all components a through inspection check.
I have run twin HS2,s for many many decades & have never had such happening before & now asking the Forum .. Do we have any similar experiences why a loose gland nut just became a leak after a year standing ..or is this something with the current fuels attacking the SU fuel transfer components from the Float Chambers to the Jet ?

[AndyPen]

Was it E5 fuel, or E10 Norman? I foolishly left some E10 in for a good few weeks and spent a while pumping out a mix of acidic water and old fuel. It softens the rubber internally as far as I am aware.

[Polarsilver]

Fuel was probably from Shell their good stuff with overwintering Fuel Fit included but even with that added i am not that confident any more to use with these modern fuels .. anyway after winter i now suck out all the stored fuel even from within the Float Chambers .. becomes patio weed killer.
What was proven is the standard HS2 Heatshield did its job & deflected the Petrol Leak away from the LCB Manifold.
Looking on the Burlin & MS sites there is no mention of their "new" Jet assemblies being E10 safe so assume they are ? .. i will now try to find a better solution as there is a Petrol Station in Buckingham that sells "Pace Leaded Petrol" so they will be supplying my fuel from now onward & maybe the patio weeds will also be happy

[gs.davies]

My only experience is with fitting the jet tube and not locating the o ring correctly. This led to the same fuel leak you saw on your car.

I use E10 almost exclusively and haven’t had a problem since going through the fuel system and making sure everything is renewed and compatible.

Might just be that your o ring has disintegrated.

[timmy201]

From SU: