Re-seating a Thetford 735 bellows?

[delliottg]

During our last freeze cycle here in the PNW, I left water in the top reservoir of our Thetford 735. I deliberately didn't fill it all the way to allow for possible ice expansion, even though we run a cabin heater constantly over the winter, plus we're on a river so there's constant flow past the boat, so I thought ice was unlikely, looks like I was wrong. When we got to the boat this past Saturday, we found standing water in the head, maybe a quart at most. It turns out the Thetford has developed a slow but persistent leak around the base of the bellows pump, of course towards the back where it's harder to get to.

My question is, is it possible to remove & reseat the bellows somehow? I asked this question of Thetford, but their response didn't provide enough information. I also asked where I could get the replacement bellows assembly, but they didn't even bother to answer that part of the email. I've asked for clarification, but so far no response. I tried turning the bellows & gently pulling on it to see if it'd move, but I didn't see movement in either direction.

Am I better off purchasing a new porti-potty, or can this one be repaired? If it can be repaired with spare parts, where do I get them in the Seattle area, or online?

Thanks for any help.

David

 

[Peggie Hall HeadMistress]

IMO you'd be better off replacing the whole thing

It'll prob'ly cost you almost as much for the parts than a whole new unit. If the holding tank is ok, salvage it to use as a space tank in case you need one.

 

[caguy]

I bought my bellows from Sears a couple of years ago for $24 I think that included shipping. I bought some earlier from an RV store that must have been on the shelf for years. They crumbled on the way home.

 

[Peggie Hall HeadMistress]

My concern...

is that--from his description anyway--it doesn't seem to be the bellows that's freeze damaged, but the seal around it and possibly a crack in the reservoir itself.

There are usually a zillion portapotties for sale on eBay...do a search using "portable toilet(s) (with and without the "s")..."thetford," "marine toilets"...
If yours is an MSD version (permanently installed, fitted for pumpout), those fittings are in the holding tank...so you can replace the holding tank in a camping or RV portable Thetford with your existing tank.

 

[delliottg]

Peggie & Frank,
Thanks for the help & suggestions. I managed to find the bellows available online after lots of searching (and little help from Thetford I might add). An RV place in Houston carries them, and I've ordered the part. At worst I've wasted $23 or so, at best I get our PP working again without having to buy a new one. Hopefully I don't have the same crumbling experience as you Frank. And even if I do end up with a new one, we can still use this one while camping or whatever, just don't put it somewhere that the water can do damage.

Thetford did send me instructions for removing the bellows though, so that's helpful. Basically they read "carefully pry out the bellows assembly with a screwdriver while not damaging the surrounding tank". At least now if someone else comes looking they know what to do.

And FWIW, ours is the non-MSD version.

Thanks again,

David

 

[delliottg]

Or not...Just got email from the company stating that the piece I'm looking for is no longer made, but they have a replacement piece at twice the price.

Hmm...I'll have to consult with the comptroller, would we rather have a nice new toilet in the head, or deal with this one? Now I'm starting to lean towards the new one. Do you have a favorite you recommend?