The Word

Just a heads up for you Boater Sam is talking absolute rubbish - the hex headed blanking plugs are 5/8 UNF, available here ASAP https://www.asap-supplies.com/bmc-leyland-outlet-fitting-for-water-heater-206799 1/2 bsp is massive compared to 5/8 unf. I have tapped a head with a damaged thread to 3/8 bsp before now, that was done with the head off in a well equipped machine shop not in the bowels of a boat! use the rear most fitting - it’s much more easier to get on to! for the return tee into the hose from your skin tank to the water pump hose, you are likely to find that much easier to get a tee for it. from memory the water pump hose tail is around 1 1/4 (32mm) so a 28mm solder ring fitting will be far too small. Hope this info gets you on the right path and steers you away from some of the nonsense you have been given passed off as fact ?