I work for a houseboat charter company, what we have done is stuffed a peice of pipe in the drain holes and put a ball valve on the end, winter is a snap just go and crank all the ball valves open. You say there is a full time mechanic around, might be worth the money to have him install such a system for you
With a ball valve it all opens right up and with a peice of straight rod you can get in there and poke around
You are correct in that I have searched and cannot find these fittings. I did discover that the blue plugs are 1/2" - 13 thread and I have located the taps and dies and am considering making my own adapters. I think the problem with just removing the brass fittings and changing to 1/4" is getting a tool on the fittings. The same fittings I have trouble getting the blue plugs back into I am not sure that I can get a tool on the brass. A 2" adapter that would screw into the brass would be much easier to install and to drain. I haven't figured this out entirely since the blue plug is a straight thread and not tapered like a pipe thread. If I can get the OEM fittings out replacing them with some 1/4" brass nipples about 2" or 3" long with ball valves seems like a good idea. Perhaps using a brass "T" on the sensor with it being on the T leg so I can rod out the fitting straight through if necessary.
I didn't plan on buying this. I just thought it was interesting and wanted to pass the info along to someone who might.
