Thanks Denny, Having built the machine from plans, I do speak
hombuilt.
And I agree with your list of potential problems.
However, I will send you a beer if you can point me to a vendor who
will sell me a new diaphram for the pump. I sure have not been able to
find one. Do you think there might be an automotive diaphragm that
would work?
At this point, my money is on the inlet check valve leaking.
Sometimes. At shut down, the pump seems to hold pressure between
itself and the carb.
I hate to replace the pump not knowing that it is the problem, but I
am running out of ideas.

Thanks
Tim.


On 18 Dec 2006 08:33:20 -0800, "Denny" wrote:

Not necessarily... The leak can be contained and yet the pressure will
be down...
There are other possibilities: worn eccentric on the cam, worn plunger
rod, bad spring on the regulator, etc... But if it had been fine and
suddenly the pressure turned up low it is likely something sudden such
as a cracked diaphragm...
Parts can be had from a number of repair shops and or vendors.. Look in
Trade-A-Plane... Check on Sacramento Air Ranch, as one source of
parts...
The first thing is to pull the pump and have someone who speaks
homebuilt aircraft help you inspect it... Usually something will be
apparent...

denny

Tim Hickey wrote:
Thanks, Don, Good advice. I will


Zenith CH-300 Driver.