The 'E' Type Forum

Trying to stop an overflow situation on the middle HD8 carb (not starting the car frequently enough, probably encouraging sticking shutoff). The brass float appears to be doing its job, but I have a query regarding the adjustment of the float lever. My carbs have a plated needle with a sprung ball bearing one end and a black coloured conical point at the other (see photos). The lever arms appear to be set at the stated 7/16 (11mm), but according to my workshop manual, at this setting, it is important that the straight portion of the lever is flat. On my car, this is not the case.

So my question is whether keeping the lever flat portion parallel to the lid mounting face is important for my setup, as I believe earlier needles may have been different. I can see that this may not allow the valve to close reliably as the fuel level rises, but before I mess with the lever, I'd like to understand a bit more.

Having watched this, in the past, taught me everything I wanted to know about SU's, hope that helps.

I think its more important that lever is set with the correct dia bar, that detrmines the float levelo, not whether the lever is horizontal or not. Check that the float needle is not sticking or seating properly . If you hold the float chamber lid upside down with light finger pressure on the needle you shouldn't be able to blow through from the inlet side. Connect everything up & remove the dashpot & switch the ignition on, fuel should not rise above the jet level. If it does, or it it flows out the vent tupe you could try a slightly thicker bar, i dont think its that critical . Also check that you have the serrated fibre washer below the vent tube banjo.

Just another thought is that if the needle is short like yours is, the lever coul be exerting sideways force causing it to stick, some judcious bending of the lever near the pivot end might help, or get another needle.

Thanks for that - I did find that I was missing the fibre washer under the vent tube banjo, which I guess explains why predominantly the inlet path filled with fuel rather than expelling via the vent.? I'll see if I have one and reassemble and check. I had checked by blowing down the fuel inlet, and that seems ok.

Hi Richard....there are different covets and forks i think you may have a mis match between the float bowl cover and the float fork.....its not uncommon to have the incorrect ones fitted....look up Joe Curto su float bowl cover video on YouTube...its all explained in detail.. Steve

Richard, if you end up buying parts from Burlen you might wish to check on what they see as compatibility with ethanol. Viton tips, change from brass floats and other bits seem to be what they suggest from discussions at Beaulieu last weekend. Good luck.

Geoff

Thanks Geoff...sounds like another tin to add to my can of worms collection!