Before wasting even more time and money trying to solve the problem
by trial and error, MEASURE the fuel pressure! Look for a pressure gauge
in the parts place, or improvise with something like a dial tire pressure
gauge, etc.
If you have no luck finding one, try this: Get about 20 feet of thin, cheap
clear vinyl tubing,
connect one end with a T-fitting to the fuel line at the carb, and attach the
other end
to the garage roof, a tree, etc. so that it goes straight up. (Leave the far
end open).
Then see how far the fuel rises in the tube. One PSI of pressure will lift
water about
two feet, so I suspect gasoline will rise about 2.5 feet. (The density of
gasoline is about 0.69).
If you have a correct value for the density of gasoline, this pressure
measuring technique
is very accurate.
Doug Braun
'72 Spit
At 04:22 PM 10/30/2003 -0500, Paul Meyer wrote:
>Hello again everybody.
>
>In my last post, I explained that my stock ZS carb had given up the ghost, and
>3 rebuilds had not been able to resolve the main problem - that of raw fuel
>overflowing from the carb vent after a few minutes of running.
>
>I replaced the carb with a new Webber DGV 32/36 and was amazed that it started
>and ran quite well - for a few minutes. While waiting for the engine to reach
>full operating temp, I observed that raw fuel began to drip from the
>secondary, and then the primary. Once it started the car began to belch and
>cough.
>
>I have a mechanical pump - one I paid a little extra for back in April. 3
>rebuilds and now a new carb is having a similar problem. Oddly, I've put
>several thousand miles on the fuel pump and old carb before this started.
>Could the pump have suddenly begun putting out a higher pressure? or am I
>simply incapable of checking a float height correctly?
>
>How many votes for swapping the fuel pump?
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