The flowlock is threaded each side with female?M14 1.5 pitch threads bottoming in a flare. On the tank side this receives an olive which is compressed around the steel end tube incorporated into the "U" shaped composite pipe from the fuel tank banjo. The olive is sealed to the flowlock by an M14 compression nut. According to the various parts diagrams for the pre-86 cars, on the pump side the flowlock is sealed to teflon pipe using an olive as well. However in the flowlock I bought, on this side the M14 thread is converted to 1/4 BSP by means of a double male adapter: The M14 1.5 side of which has a terminal male flare to seal into the olive space inside the flowlock without an olive and converts to a male 1/4 BSP male thread, again with internal olive compression flare. This privides the same thread as that on the pump where the internal (female) 3/8 bsp thread is converted to 1/4 BSP male, by means of an adapter which seals by compressing the O ring on the pump against the flange of the 3/8 to 1/4 BSP adapter, again terminating the a 1/4 BSP male thread with an internal flare to take an olive. This presumably allows a simple pipe with bsp 1/4 compression joints at each end to be fitted. Although necessary to convert to Lotus compression unions this although this . If replacing the M14 adapter in the flowlock with a sealing washer, the length of the flange to thread end cannot be more than 8mm or the thread will bottom out in the flowlock before it compresses the sealung washer. Similarly, if doing the same in the pump the 3/8 BSP thread should be no longer than 0.7 mm and the flange should be larger than normal to compress the O ring evenly.
I sold the car before I solved this fitting conundrum!
