Potable water tank access panel

Jul 7, 2004
8,032
Hunter 30T Cheney, KS
Can't seem to find the discussion on this. After I cleaned the sludge out of the intake side screen on the water pump, I thought I better get inside my tank and clean it out. My tank is plastic. I have a 4" hole saw. Can I just fasten a round 4" access panel to the top of the tank? What should I use to seal around the fasteners? I think I might use machine screws with oversize washers.

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Jan 11, 2014
7,855
Sabre 362 113 Fair Haven, NY
Here's a thread on this very topic:
 

JRacer

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Aug 9, 2011
1,239
Beneteau 310 Cheney KS (Wichita)
Just a heads up. If you have a float in the tank and it has any electronics on it, IC board, I would not recommend using any vinegar to clean the tank. I did that and found that, I presume, the fumes from the vinegar left over in the empty tank corroded the IC board on the float mechanism. The next spring, I had to replace the float.
 
Jul 7, 2004
8,032
Hunter 30T Cheney, KS
Just a heads up. If you have a float in the tank and it has any electronics on it, IC board, I would not recommend using any vinegar to clean the tank. I did that and found that, I presume, the fumes from the vinegar left over in the empty tank corroded the IC board on the float mechanism. The next spring, I had to replace the float.
Didn't know that but I don't have that fancy Bene. ;)
 

JRacer

.
Aug 9, 2011
1,239
Beneteau 310 Cheney KS (Wichita)
And, now for the rest of the story. The float, wiring and the water gauge were not OEM. I installed it the first year I had the boat. While doing that, discovered that the tank needed some cleaning and cleaned it with a vinegar and water solution. Cleaned it all out, dried it out and left it over the winter. Come spring, found that the electronics on the float were corroded. Learn something new every day, sometimes the fee for the class is high!