H36 2008 holding tank issue

[George Braun]

new-to-us 2008 H36. The holding tank outlet fitting that is welded onto the tank is cracked. is there any other fix than replacing the tank?
Second question - the tank is secured by two brackets that are visible, 2 screws each. Do these actually penetrate the interior of the tank? Already planning to replace all hoses, if they are original have held up well but time to go. Just a tiny bit of smell at this point, but boat has been very lightly used up to now, we plan to change that. Previous owner evidently sailed only about 50 miles last summer, we're already pushing 250, so head is getting used.

 

[Peggie Hall HeadMistress]

oops...apparently somebody over-tightened the hose fitting when they threaded it into the tank. Unfortunately the only cure for a cracked HOLDING tank fitting is a new tank 'cuz you aren't likely find anyone who'll go near a used sewage holding tank. If you're lucky to find a plastics fabricator who'll touch it, tell 'em it's a a simple exterior spin-welding job.
It looks to me like those brackets go through an "apron" that doesn't provide any access to the inside of the tank.

However, you may have an excuse to upgrade your tank...to something larger, maybe or a better location for it...improved fittings sizes and locations..
Ronco Plastics Ronco Plastics marine Tanks is your best source. 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

 

[George Braun]

thanks, Peggy, that's about what I was thinking, damn it. Gonna be a big job to get it out.

 

[George Braun]

anyone know who made custom tanks for Hunter in 2008? detailed look at Ronco catalog came up empty.

 

[Peggie Hall HeadMistress]

You haven't had time to do more than scan the 400 drawings in the Ronco catalog, George!

Most likely it was Duraweld (formerly known as Duracast). Their standard wall thickness is only 1/4" which, unless it's a fairly flat tank, will have to be supported on all vertical sides hold the 8.333 lbs/gal weight of water or sewage. They'll make a 3/8" tank, but only for a killer upcharge.

Send me a PM if you want to work on this together.

--Peggie

 

[isaksp00]

Just out of curiosity, is it possible with thermoplastics to melt in a "weld" on the cracked fitting using something like a hot knife, soldering iron or wood burning tool? I've fixed small holes in kayaks that way?

 

[Peggie Hall HeadMistress]

It won't work for a few reasons: 1. A successful weld requires melting quite a bit of new PE together with quite a bit of existing material that also must be melted so they run together to form a single mass of plastic...2. which would require complete accurate replacement of all the threads in it to be able to thread a fitting into it...

Once a PE tank fitting is cracked, the only way to repair it is to knock out the entire existing fitting and spin weld a new one in.
If you REALLY clean out that tank, there's an outside chance that you MIGHT find a plastics fabricator who'd do that. Hed be unlikely to have the fitting on hand, whether he can even get it is up for grabs. But worth a try.

--Peggie