Larger Holding Tank for Catalina 34 MK II

[Roc]

My boat was also plumbed with a vented loop from the Catalina factory.

[Peggie Hall]

A sailor friend put a ball valve in that spot in place of the vented loop which works OK but you still have to remember to close it.

Whaaa???   A ball valve is just shutoff valve...a vented loop is an anti-siphon device that when installed correctly (and maintained) works all by itself without the need for any human intervention. So replacing a vented loop with a ball valve makes NO sense whatever!

[Fred Koehlmann]

Cory: I was up at the boat this weekend (getting it ready for haul out) and re-measured the storage locker. There are some very tight dimensions and I'm a bit concerned about the top clearance. I agree with your suggestion about making a model or mock tank. I was thinking that corrigated cardboard might be the light easy way to go about it. However I noticed that a dimension was missing... so I've emailed Ronco to see if that can fill in the missing data. I'll be up again this weekend, if you want to drop by and talk about it.

Peggie: The science is clear and makes sense. The only reason I removed te vented loop was on suggestion from the marina that sold me the replacement pump. I never completely removed the hoses, so they'll get swapped back into place. Yes, Catalina did have it right.

John: Yes, that is what I was thinking about; Loop the head output up and through the hanging lock (not under it) and down into the tank.

[Peggie Hall]

Styrofoam sheets are a lot easier to cut with a box knife than corrugated cardboard. And once you've put all the other sides together (another fine use for duct tape), it should be obvious what the dimensions/size of the last one is...you'll have the shape of it.

[scotty]

There is a type of poster-board that you can buy at art/office supply stores.  The inside layer is foam, sandwitched between two (thin) pieces of heavy stock paper.  It is easy to cut (cut it like drywall) and holds shape well.  It would be good for making a mock-up.  Oh yes, it's pretty cheap.

[Mike and Joanne Stimmler]

A sailor friend put a ball valve in that spot in place of the vented loop which works OK but you still have to remember to close it.

Whaaa???   A ball valve is just shutoff valve...a vented loop is an anti-siphon device that when installed correctly (and maintained) works all by itself without the need for any human intervention. So replacing a vented loop with a ball valve makes NO sense whatever!

It may have been an easier option for this owner, it was on a Erickson 380 and the ball valve was in the short piece of hose just behind the head and mounted on the wall. His logic was that it less obtrusive looking than a vented loop in the same location and it was convenient to turn on and off when using the head. I guess it comes down to the same old addage,"his boat, his choice"....same end result(if used properly).

[cmainprize]

Hi Fredrick

I would be happy to get together to dicuss this project.  We were up at the boat for the last couple of days but a crash gybe and a serious injury to a friend cut our trip short.  I may post about this when his face stops looking like he was hit a 12 foot long eighty pound aluminum tube going 60 miles an hour.  All things considered he was very very lucky but he still got hit very hard and will have some nasty scars to remember his trip.

My boat is not coming out for a couple more weeks, but one way or another the factory tank is not going back in.

Are you guys at bayport?

Cory

[Fred Koehlmann]

Cory: Yes, we are at Bayport, and Dolphina should be coming out tomorrow.  I will be up this weekend (mostly Saturday) to set up some sort of framing so that Topline can take measurements for a winter cover. Feel free to drop by anytime.

I spoke with Ronco and the missing dimension is 5-1/8" (see image). The red squares represent confirmed right angles. Also I was told the shipping would cost $113.53 US and $282.09 US for the tank.

All: Thanks all for the modelling advice... as an ex-architect I use to work with all these materials. Cory and I will talk this over since I suspect he'll want to check his locker out as well.

[Fred Koehlmann]

Well, I finally had the time to build the model tank... here it is. Planning on taking it up to the boat today and see if I can get it to fit in. I have no idea of how much fun it will be to take the existing one out. I do need to take it out carefully so it doesn't get ruined, since we don't know if the B179 will fit.

Cory: I plan to leave it up there. If you're about Sunday evening or Monday we can compare it on your boat as well. I know its Thanksgiving... we celebrated Saturday, knowing that I probably wouldn't be around. That said, I should be up next weekend as well (our winter cover should be ready by then).

[Fred Koehlmann]

I managed to get up to the boat before sunset, and the existing tank came out not too badly. I damaged one hose a bit, but I was planning on replacing them anyway. Not too much stink, since we did rinse it out a fair bit before getting hauled. Here are the photos comapring the two tanks; the existing B212 (18gal) and the B179 (30gal) model.

[Fred Koehlmann]

So the inital verdict is rather disappointing. THe tank in plan looks like it's going to fit but... The tank appears to be too high!! Arrgg!! Oh well, I guess that's why I made the model. I do have the through hull fitting below it, but I cut out a section of the model once I could accurately identify where it would impact the tank, so that was taken care of. Basically the forward dimension is to high, and when you consider that you need to e a couple inches lwer to fit the vent hose in, I figure that it's about 2" - 3" to high.

I'd love to know what years the Catalina 34 was outfitted with the Ronco-B179 30 gallon tank and how their port settee is configured. Basically wha are the differences that make it too tight on the MkII. Was the settee higher, or was it wider anthus possibly the hull slope allowed for it.
Cory: I'd love to see how the model will fit into your space, if you are interested.

We for us we need to do some thinking about options.
1) Take up the hunt again to a differen tank.
2) Consider modifing the settee to accomodate the tank. That means raising the settee.
3) Put the 18 gallon tank back in and make note of all the pump out locations that I can find on Georgian Bay.

I'm going to have to sleep on it.

[DarthOccam]

Arrgg!!

Frederick,

Thanks for the great pictures and detailed account.  I was rooting for it fitting, but the space is very small. 

[scotty]

I used to own a Catalina 30.  The engine was to high for the settee, by an inch or two.  The cushion was scooped out in the underside.  It was just a bit noticeable when sitting, but not a big deal.  The area involved was about  a foot by a foot.  Would that idea work for you?

[Craig Illman]

My 1991, hull 1150, had a B-179. The macerator was mounted at the aft end of the settee compartment where the battery switches are on the newer boats. It couldn't have been a millimeter taller, the vent line elbow was hitting the settee cover. The settee covers weren't integrated into the cushions lie the newer boats.

Craig

[Jim Hardesty]

Fredrick,
Thanks for sharing your work.  I know that when cruising some legs and stops are dictated by pumpout availability, bummer.  Catalina really should have rethought that downgrade to the MKll's.  One thought that I've had is to add a second tank, perhaps aft of the head, port side under the berth.  My thoughts are a selector Y-valve at the head, a separate vent and pumpout fitting, and electronic tank monitors.  But then, I've not measured anything.
I wish you luck, rooting for you.  And, please, continue to share.
Jim