No, the solution would be to replace the worn arm and pin.
I had that happen to my MGA once, the overfolw at 3500 rpm that is (dunno
about the worn float valve arm) when autocrossing, and at full throttle
only. I was using an aftermarket fuel pump at the time that put out about
5 psi static pressure, 4 psi at idle, and more like 3 psi at higher flow
rates. I installed a fuel pressure regulator set to 2-1/2 psi and the
problem disappeared.
I don't thing the pressure alone would cause this problem, but probably a
strange combination of pressure and flow and worn parts could cause a
resonant vibration that would keep the float valve open. Changing any of
these parameters (like fuel pressure) would change the frequency where the
problem would occure, or likely eliminate the resonance completely.
Another change that might help in this case would be the type of float
valve. An all metal valve would aggrevate the problem, as it would readily
transmit vibration from the body (lid) of the float chamber through to the
float arm and excite the motion of the float. A grose jet for instance is
all metal construction, and I did have Grose jets installed when this
happened to me. Some float valves have either a spring loaded tip or a
rubber tip, and some have both. One of these valves would cut down on
transmitted vibration, and likely reduce the possibility of vibration
induced overflow.
Barney Gaylord
1958 MGA with an attitude
http://www.ntsource.com/~barneymg
At 07:06 AM 9/3/99 -0400, j r overcash wrote:
>So the solution is to replace the floats?????
>
>Ross Overcash,74B,NAMGBR 1172
>Ayer, MA
>http://www.tiac.net/users/jroverca/index.htm
>
>> -----Original Message-----
>> From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net]On
>> Behalf Of R Sovatsky
>> Sent: Thursday, September 02, 1999 12:19 PM
>> To: MG List
>> Subject: OVERFLOWING SU CARBS
>>
>>
>> This tech tip, by John Twist, was in the SOL Tech Page (wasn't one of the
>> listers having flooding problems at about 3500 rpm???)
>>
>>
>> OVERFLOWING CARBURETTER -- There is an unusual problem that will allow
>> the carb float bowls to overflow at speed. If the floats have the metal
>> fork, through which the axle pin passes, and if these metal tabs are VERY
>> worn, then the float can vibrate in a certain harmonic with the engine and
>> allow gasoline to pass into the float bowl, even if the bowl is
>> full. This
>> results in overflowing and a distinct gasoline smell in the cockpit.
>>
>> Bob
>>
>>
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