Wow, some great in put here thanks Guys. David, as you know I have pretty much copied your set up with the electric pump for all the reasons I highlighted above, and a pressure regulator with filter. Previous to getting the tanks resinstalled and making up new fuel pipes, I was running it on a Jerry Can with a small electric pump on the top. Made as a "get me home for the DUKW, if I got fuel pump/tank/line problems whilst at sea. I didnt fancy gradually sinking as I tried to get to grips with where the problem lay, sorry I digress. On the Jerry can the Carrier ran well with no overfueling problems but it did feel odd at higher revs. Almost as thoughyou had to keep accelerating to maintain steady engine revs. I did wonder whether the main jet was blocked and it was only working on the power jet and accelerator jet, but since it is a brand new Carb and really perfect, I dont think it is that. This led me to think that the electric pump on the Jerry can was perhaps not producing the flow necessary and therefore after accelerating there was a momentary loss of fuel requiring a few miliseconds to recharge.
Anyway, without getting to the bottom of that problem I have now fitting all new, copper, fuel line, new original specification "junior" fuel filter and as already mentioned the electric "facet" and fuel regulator. I too , have set this at 3.5 psi.
If the pump is left on for too long without starting the engine, it will overcome the carburettor float valve and flood. It may well be that the engine was designed to receive fuel at this pressure but of course the advantage of a mechanical pump is that it will not pump unless the engine is turning over, unlike the electric one.
I do worry that I may have too much head for the pump to manage to keep up with when the engine is running. In other words, yes it will flood when the engine is not turning over, but MAYBE as the pump and filterking are mounted high up it cannot keep up when engine is running? I have mounted the pump about the same height as the carburettor which is about 3 feet above the bottom of the fuel tank, which in turn is about six inches higher than the original fuel pump.
On the fuel return pipes, I fully get the advantage of returning unspent fuel to the tank, and have long been told that this will help remove the vapour locks back to the tank. However, since there is no obvious way to achive this without creating new pipes into the two fuel tanks ( or just one I suppose) I have left this alone. The Filter King advertises that it is able to negate the effects of vapourisation in its design.
http://www.demon-tweeks.co.uk/perfor...tor-and-filter
I am sure I am somewhere near achieving correct running but as Lynn says, it could be as simple as a vacuum leak somewhere or even a fault with the Governor. More digging is needed, and its stopped raining here in Kent, so I am off to play now. thanks chaps