I dry tested the bow tank of my mk2 today. When I pulled the bung out, about a litre of water came out. “Oh dear”, I muttered. I assumed it must be leaking in rain water from the bilge side of the tank. The bilge had about 5l of rainwater in it because I forgot to open the bailers. I conducted the test and it passed. It took 6mins to drop from a 125mm to a 50mm differential. Is that good or bad for a bow tank?
The only variable I could think of was the bung. It’s a brand new triangular, push fit Allen unit. I use the same type on the test rig and it seals perfectly, no soap sud bubbles.
I replaced all the original bungs with new. At the time I considered swapping to screw fit but thought better of it. Was this a mistake?
Considering the rules allow for a differential drop of not less than 30 seconds then 5 minutes is very good. The original MK 1 boats had just a rubber bung and they work fine. I have not had mine out for years.