Mark Rand wrote:
On Tue, 08 Jun 2004 12:13:41 -0500, Jon Elson wrote:


Hello, all,


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This all works great, but the diaphragms keep wearing out.


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Just a thought... Did you design in too much movement on the diaphragm? What
sort of pressure limiting do you have in the system (1/2 psi ought to be
enough for the carburetor).


The little header tank for the carb is 1" copper water pipe, with a
float switch in it. If the fuel pump fails to shut off, the air
vent back to the tank becomes an overflow drain. The diaphragm
has a fender washer about 3/4" OD on each side of it, and the
stroke is somewhere around 1/8".

Thanks for all the useful comments, I'll have to do some
more research.

Jon