Hunter 30 tanks

[sandpiper10471]

Holding tank, under port Vberth, and water tank, stbd. settee, appear to be molded to the tops of each bench. There is a large fiberglass plate screwed into a recessed lip on each and each one has a leaky inspection port. Based on each lid being covered in white caulking and many tubes of clear silicone then covered in gorilla tape, I suspect that effluent discharge through the tops has been an ongoing problem. How have other H30 owners dealt successfully with this construction?
I am reticent to criticize the design. It could be fine, or perhaps not. It is a new-to-me 44 year old boat. Looking for thoughts and wisdom.

 

[ggrizzard]

I assume your Hunter 30 is a Cherubinni version.
I own one and to my knowledge, there were no factory installed holding tanks in that model.
Mine came with a recirculating toilet with overboard discharge or deck discharge.

Perhaps other owners did a retro fit and will respond

 

[sandpiper10471]

I assume your Hunter 30 is a Cherubinni version.
I own one and to my knowledge, there were no factory installed holding tanks in that model.
Mine came with a recirculating toilet with overboard discharge or deck discharge.

Perhaps other owners did a retro fit and will respond

81 Cherubini. I am assuming factory as the screwed down lids fit in to a recessed, molded flange.

 

[heritage]

I think the design of the tanks are sound. They save space in the boat, versus a tank that is designed to fit in an odd space and hold down straps are not needed. The fiberglass lids to the tanks are quiet large and take a while to remove all the screws to inspect and clean the tank, but once removed you have excellent access to the inside of the tank. I did install a Beckson port in the water tank lid so I could quickly add water and not overfill the tank. Never had any leaks on my H27.

 

[Dalliance]

Same design in my ‘82 H30 for both water and waste. Definitely original. Custom fiberglass tanks tabbed into the hull with full size fiberglass lids set in a flanged sitee platform with silicone sealant and screws about every 3 inches. The tanks are an integral part of the sitee platforms which are part of the one piece dropped in interior hull liner.

I’ve been lucky to date. No leaks. If the lids ever do leak, I’ll be removing a lot of screws, digging out old silicone sealant and resealing with the same. I think that’s what you need to do. I don’t know if the silicone around my tanks lids is original or not, but it appears the PO of Dalliance added two more access ports to the baffled water tank for cleaning. If an access port is leaking, it might need a new O-ring, re-bedding or replacement if it’s cracked.

My worst case concern has always been what might happen if one of the tanks underneath fails. Then it’s either a fiberglass repair job or cut out and replace with a bladder type tank I guess. Though removal might compromise structural integrity of the sitees and possibly more, so that’s probably not the direction I would choose. Fortunately they seem quite sound so far at 43 years old.

Overall I think it’s a pretty good design and very space efficient.

PS: Before anyone comments on the clear vinyl hose in the waste tank photo, it’s a permanent winterizing hose attached to a three way valve just above the intake through hull valve. Not depending on it to handle below the waterline water pressure.

 

[Intrepid-II]

I have an 82 Hunter 30 and I just added 2 additional inspection/cleaning hatches to my water tank so I could see/clean the other baffled compartments. I went with the next size up to make it easier to get my arm inside the tank. See attached before and after pictures.

 

[Intrepid-II]

With respect to the problem you inherited, you will just have to literally dig in and clean up the mess. Any work involving the holding tank is going to be a shitty job. Start with pumping and flushing and pumping and flushing and then remove/replace all the old hoses as they will also be holding stuff and be stinking. You will have to use solvent to clean up the tape glue and then start digging out the hatch sealant. You will have to remove it all and if silicone was use will have to get it dissolved/removed because nothing will stick to it not even more silicon.

The worst case is the tank was full of stuff and water and not winterized and then it froze into a giant block of ice and that is what broke the seal on the lid and more than likely damaged the integrity of the rest of the tank by cracking the gel coat and fiberglass. You could still fix it but you would have to consider how you want to use the boat and if it would be worth the time and effort.

Switching to a composting head might be an option worth considering.

 

[sandpiper10471]

Thanks for the suggestions, replies, photos. Faith restored. Hoses are pretty new and don't smell. I think cleanup and rebedding is all that is needed. 3M4200 or sikaflex equivalent suitable? I DETEST silicone.
If I were to go composting, which a number of my colleagues have suggested, I would still need to clean the tank. Mask on, dig in.