GB 36 holding tank replacement

[Moersea]

I’m looking at replacing the holding tank on a 36’ Grand Banks Classic (1989) and wondering if anyone in the forum has experience with this job? The tank in this layout (twin Cummins) is behind and partially under the generator.
Comments, cautions, and hints all very welcome!

 

[HeadMistress]

There's no rule requiring the new tank to be in same location or even the same size as the the original tank, so feel free to investigate locations that are closer to the toilet and/or need less complicated plumbing etc.


Fwiw, Ronco Plastics Ronco Plastics marine Tanks is your best source for a tank. They make TOP quality thick-walled (50% thicker than most other mfrs) water and waste tanks for a very reasonable price and have more than 400 shapes and sizes, over 100 of which are non-rectangular, and they install fittings--including diptubes--in the sizes and locations specified by the customer when they make the tank. There are retailers who sell Ronco tanks, but Ronco sells direct for a much lower price...and they're great to work with.

When looking at drawings it's important to know that there is no top or bottom until the fittings go in, and YOU decide where they go. So rotate, flip in any orientation to find the tank that fit your space.

--Peggie

 

[Bacchus]

Perfect time to research and plan your tank venting!
Large size, straight, short vent runs are a real plus.
I would suggest including a plugged opening to add a bubbler if desired, in the future. IMO it is possibly the best alternative for avoiding any tank smells. The DIY version is very inexpensive and surprisingly durable.
https://dkloeber.wixsite.com/bacchus/projects-pg-2