please build a cam onto the valve stem (of the return valve)

and have the cam turn on the pumps (via switches) so that

fuel source

follows fuel return automatically.

Another way to do this is to use one of the pump switches

to also turn on an

electric solenoid valve, thus switching the return to

that tank.

John Slade
Cozy IV

John,
do you have any particular type of solenoid valve in mind? The

upside is that one switch would switch tanks and  fuel return.

The down sides are that there are more electo-mechanical

devices to break, is there a provision to run both pumps for
critical operations?. And, there might be fuel return issues- too
much fuel back to one tank, resulting in an overflow.

 But, in a worst case scenerio, the worst I could do is dump

only half my fuel. : )

Other people have suggested using the  manual fuel return

selector to actuate the apropriate fuel pump through the use of
some sort of microswitch or some such thing. If I can figure out
a way to build a robust enough setup, that might be the way to go.

Decisions, decisions,....

Brian Trubee

John Slade wrote:

Yes. I got one from my local hydraulics suppy store for about $70.
the valve is made by Vickers. If the valve is off or fails, fuel will return
to the right tank by default. If it's on, fuel goes to the left tank. Its
available from Aero Hardware Supply tel. 800-507-9651. Part numbers are VICK
SV4 10 3 0 00, VICK 30545 and VICK 20197AA8. The AN flare adapters are part
number AQP ADP 6M ORB 6M JIC. When assembled with the flare fittings it
weighs in at 33 1/2 oz. See http://kgarden.com/cozy/chap21b.htm about half
way down for pictures of it installed.

The manual six port valve you mentioned is probably the one by Andair. It's
nice, but it's $400+ and there have to be a lot of pipes in the cabin for a
pusher.

Andair has a torque tube arrangement that allows the valve to be mounted aft.
Unfortunately also expensive.

Paul Lamar
 
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