My 3 litre AC fuel pump is playing up. Before I dismantle it and cause further problems, does anyone know where spares can be obtained, or someone that can overhaul it?  I only keep going on my standby SU pump (which I installed simply to fill the Kigas before cold starting):  without its help the running is awful, so I guess the AC pump needs a  rebuild. I imagine modern fuel has upset th diaphragm at least, and perhaps the valves are clogged.      Help would be appreciated!   Nigel Hall