24V fuel system
Posted: Tue Dec 06, 2022 3:31 am
Hello all,
My first real post other than introduction a while back. I look after a customer's militiary 24V, which I've just completed multiple jobs on, including removal of the restrictors. It's running on a pair of Stromberg CD175's which I believe are factory? Here is the layout of the fuel system which I believe to be the cause of my issues:
Twin underseat tanks, sender in each tank.
1 x 24V electric fuel pump, unknown brand.
1 x changover valve in right footwell which mechanically controlls which tank the pump pumps fuel from and electrically switches the sender accordingly. The supply splits just before the left carb, therefore feeding both carbs.
Return goes back to both tanks constantly regardless of which tank is being used, which isn't ideal as the tank being used is only receiving half the return therefore depletes even faster than it should!
From my searches on this forum, it seems there should be a pump for each tank, controlled by the changover valve and the appropriate sender is selected via a separate switch. Or, should both pumps be constantly running (one pump per carb)? Also read somewhere here (can't find the thread now) that constant return fuel system should not have float valves? When I rebuild the carbs, they were fitted so I renewed them with the valves from the carb kit.
I would really like to return the system to standard but finding part numbers/wiring diagrams/system description is proving to be difficult. If anyone could shed any light or point me in the right direction, I'd be eternally grateful!
Many thanks,
Matt
My first real post other than introduction a while back. I look after a customer's militiary 24V, which I've just completed multiple jobs on, including removal of the restrictors. It's running on a pair of Stromberg CD175's which I believe are factory? Here is the layout of the fuel system which I believe to be the cause of my issues:
Twin underseat tanks, sender in each tank.
1 x 24V electric fuel pump, unknown brand.
1 x changover valve in right footwell which mechanically controlls which tank the pump pumps fuel from and electrically switches the sender accordingly. The supply splits just before the left carb, therefore feeding both carbs.
Return goes back to both tanks constantly regardless of which tank is being used, which isn't ideal as the tank being used is only receiving half the return therefore depletes even faster than it should!
From my searches on this forum, it seems there should be a pump for each tank, controlled by the changover valve and the appropriate sender is selected via a separate switch. Or, should both pumps be constantly running (one pump per carb)? Also read somewhere here (can't find the thread now) that constant return fuel system should not have float valves? When I rebuild the carbs, they were fitted so I renewed them with the valves from the carb kit.
I would really like to return the system to standard but finding part numbers/wiring diagrams/system description is proving to be difficult. If anyone could shed any light or point me in the right direction, I'd be eternally grateful!
Many thanks,
Matt