Betsy Fueling System


I have aquired a yammah dual diaphram pump.


This pump runs off of 100 psig compressed air. Supposedly it can pump upto 6 gpm. And can pump up to 100 psig. The wetted arts are all polypropaline and PTFE. Should be able to handle anything thrown at it.

The hope to is that the large head that this pump can handle also means that the flow rate is insensitive to small flow restrictions. Flow restrictions have been the bane of Betsys pumps, causing excesive fill times. The other problem has been priming. As this pump is supposed to be self priming to 10 feet there should be no problems.

Pump has been tested. As typical with things bought off ebay nothing is certain. Running the pump at 100 psi results in a flow rate of 3gpm which is exactly half the expected flow rate. Plus the pump has trouble priming. I suspect the one of the diaphrams is not pumping correctly.

Next step is to check the ultimate pressure. Most likely I can buy a rebuild kit for this pump. Definitely looks like one can buy replacement parts and stuff.


Disasembled the Yamada pump. Turns out the the exit manifold is cracked. The valves and other pump parts look okay. Haven't pulled the air system appart yet. Definitely need to replace the cracked manifold.


Ordered a new manifold and o-rings from:

Flo-Line Technology 530-887-2240 - Ph. 530-887-2243 - Fax