I'm switching from 1.25 inch to 1.5 inch carby. The old carby just had one fuel line connection, the new carby has two. So which is the 'in' and which is the 'out'?

The fuel IN is the higher of the two brass tubes on the float bowl. The other is an air vent.

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I assumed it was a fuel return line. So do I just leave the bottom brass fitting disconnected?

I bought a reco 1.5 inch carby from Minisport, I've just hooked it up and it is leaking fuel, looks like it is coming through the seal at the top of the float bowl, is this because I have blocked the vent or is it unrelated?

Leave it disconnected. The 1 1/4" Carb you took off actually has the same vent, only no tube on it. It was for the Evaporative Control System.

Does sound like the bowl gasket, for what ever reason, is not sealing.

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yeah, don't block it - it needs to be open so that the air has somewhere to go when the fuel goes in...



question isn't why isn't it sealing, it's why does it need to seal.... how's the float level? is the needle & seat sealing?

take the lid off the bowl on your old carby and swap it over.

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Aussie Leyland, Aussie Factory, Aussie Mini S.