Sure sounds like carb bowl heating up. Radiant heat from the exhaust
system is not being dissipated by any flowing air, so the carb bowl
heats up, boiling the fuel and pushing it out of the jet. See the
recent threads on heat shields for preventive measures.
One other possibility is a missing insulating spacer. There should be
a phenolic spacer between the carb and intake manifold, IIRC.
Donald.
> Date: Sun, 25 May 2003 17:25:06 -0600
> From: Alan Lemen <ralemen@cableone.net>
>
> I am having problems with my front SU HS4 carb. Rear one is OK.
>
> It only seems to happen when I stop the engine. Plugs are perfect
> colour, carbs are in sync.
> I did check and even replace the float valve and the fuel level in the
> float bowl is fine ( identical to the rear one), even disconnected the
> overflow pipe while it was running and it did not overflow. So stopped
> engine ( was double checking the sync so it was running for a short
> while at temp) and after a minute or so the fuel comes out the jet -
> easy to see with the filers off. Since top of jet is higher than the
> float bowl level surely it's pressure but where from and why only the
> front. Nothing appears blocked.
>
> Ideas anyone?
>
> Alan
>
> ps. No excessive fuel consumption as I just got 33 mpg on fill up.
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