In the NOC shop part no. SS14 C3 041323L is described as "Petrol tap: Lightweights only: 7/16 petrol tank thread - Use 1/8 BSP fittings: Lever type: All metal plated brass, New". I have bought one as my old push-pull tap continued to leak even with a new cork insert. The description is incorrect and has mislead me. I have found that the petrol tank thread is 1/8 BSP and the 7/16 thread is the one on the outlet. Unfortunately I have bought a Dowty washer that now won't fit the tank end of the tap and a 1/8 BSP spigot and nut that don't fit the outlet. The outlet thread od seems to be suitable for a nominal 7/16" thread but the TPI seems to be 19TPI according to my thread gauges. Does anyone know what this thread is so that I can buy the correct nut to clamp the spigot? Someone else must have bought one one of these taps.
Hi David, l also bought this tap, 2 actually, and found the problems you have. After a lot of trial and error l discarded the nuts and tails and used old ones. It solved my problem but does'nt address the question of why the originals are incompatible. Neil
You were lucky to have "old ones". The Ewarts tap I'm trying to replace has an integral spigot on the outlet.