The V3 valve is a development of V1 with a simple return system tapped 1/8” NPT for standard AN-4 or other pipe fittings.
It has been used as a return for trapped air or low volume fuel from carburettors, it is not suitable for most current fuel injection systems.
There may be some cross feed on the return as it is a very simple drum valve for low pressures and volumes.
The main valve uses the range of special SPRL pipe fittings, see the accessories tab for details.
Available as –3P (3 Port) with LEFT-RIGHT-OFF or –4P (4 Port) with LEFT-RIGHT-BOTH-OFF positions.
Note: The main valve comes with 3 AN-6 male adaptors, see "Accessories" tab for other available fittings. Must use Newton fittings. Standard AN Fittings do not fit except on the return system.
Rotax now specify -6 as the minimum pipe size for all their engines, supply and return.
FAR 23 conforming
The SPRL Valves, as designed, have a very nice 'feel' and are logical in use, many pilots prefer our standard with a lift and turn between selections. However there is a requirement in FAR 23 whereby the fuel valve must be turned from OFF to an ON selection simply by turning it, i.e. it should not have to be lifted up, pushed down etc, and it should also not be possible to turn it from an ON position to OFF without a detent. See V1/V3/V4V9 and V10 valves with a 'conforming' selector and –C in the part number.