While in Sacramento this weekend I took my ailing Holley 2 barrel to a
carb rebuilding shop. I explained my problem, namely that the carb
gaskets were all leaking, that gas was pouring out of the throttle
shaft, and the car was getting lousy milage. I was informed that one
possible cause for these faults was excessive fuel being delivered by
the fuel pump. I never bothered to check the fuel pump, but of course it
makes sense that if the pressure is too high, gas will find its way out
at the weakest point. I was also informed that worn throttle shafts were
generally not a problem with Holleys.
I was also told that the rule of thumb for determining proper fuel
pressure was to hold a quart jar at the end of the fuel line and let the
fuel pump run for one minute. The jar should just fill up, and not
overflow. This formula, coincidentally, is equivalent to the 15 gallons
per hour rating listed in the Tiger Shop Manual for the stock fuel pump.
I haven't tried this experiment yet, but my guess is that with the after
market fuel pump on the car, it probably is pumping too much gas into
the carb, and therefore causing the fuel leaks. Anyone else with a
similar gas leakage problem may want to check their fuel pump pressure
first.
The carb shop I went to was called the Carburetor Factory, and they seem
to know their stuff.
Peter Silva
'66 Alpine / Tiger conversion
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