Blocking of abandoned water lines

[Found at Sea]

I'm reducing a 2 water heater boat to just one and need to block off several re circulation lines from the engine. What would you recommend I use to cap off the soon to be unused lines other than a large bolt and clamp?

[Uncle Bob]

Originally Posted by Found at Sea

I'm reducing a 2 water heater boat to just one and need to block off several re circulation lines from the engine. What would you recommend I use to cap off the soon to be unused lines other than a large bolt and clamp?

Replace the threaded hose barbs on the engine with threaded plugs and remove the offending hoses.

[Found at Sea]

Unfortunately there are two Y's at different locations on the engine and I still need to access one line off of each Y.