Either debris in the float valve or a faulty valve preventing it from fully
closing, or a punctured float which is full of fuel and now won't - float
that is. The first can often be cleared by disconnecting the fuel pump and
running the engine till the carbs empty, then reconnecting the pump. The
resultant rush of fuel through the now wide-open valve (normally it is only
open a fraction, especially when idling) often clears it. If it leaks again
straight away it is probably a bad valve or float. If it comes back after a
while and affects either carb it is probably dirty fuel. The float is easy
to check by removing the top cover with everything in-situ, and check it is
free on its hinge. Replacement of HS valves is also pretty easy, compared
to HIFs. With a leak on a newly rebuilt unit check the float height is
correct, I suppose it could be so bad that something is stopping it rising
far enough to close an otherwise good valve. With the float chamber lid
removed and inverted, insert a 1/8" diameter bar across the diameter of the
machined lip of the float lid, parallel to the hinge pin and under the float
lever. The face of the float lever should just rest on the bar when the
float needle is held fully on its seating i.e. fully closed. If not, and
the float lever is metal, carefully bend the lever until it just is so. For
all-plastic floats you may have to shim the float valve with washers to
obtain the correct height.
PaulH.
----- Original Message -----
From: "Paul M." <rowman22001@yahoo.com>
To: <mgs@autox.team.net>
Sent: Saturday, July 10, 2004 4:08 PM
Subject: SU float bowls flooding
> ... what
> causes this and what is the diagnosis/repair
> procedure?
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