Fixed tanks for 16 Cruiser

marco422 · Posted: Sat May 29, 2010 8:48 pm Post subject: Fixed tanks for 16 Cruiser

In the quest for a 375 km range (200 nm) for extended adventures and less weight astern, I am researching a pair of saddle tanks for my 16 Cruiser. None of the Moeller tanks fit so I am thinking of having aluminum tanks made with dimensions of about 56"L x 6"W (bot)/8"W (top) x 12"H. to hold about 65 litres (17 gal) each. They would extend from the seat compartments to just short of the transom underneath. I am planning a sending unit, vent to the side of the splashwell, and pickup in each tank to a dual valve under the aft storage compartment. I was thinking of "above-deck" style fill covers installed just in front of the aft storage compartment.

Can anyone give me any advice about this project? Might I be better off installing regular fill plates in the splashwell sides or would this cause problems in case of a spill? I suppose I could use transom plugs in the splashwell drains while refueling in case of a spill since it's probably better to spill in the splashwell and mop up rather than inside the cockpit. That would have the advantage of keeping the tank tops inside the cockpit clear so there is a nice step/seat on each side. I know for some this would interfere with fishing, but I never fish and generally use the boat for long-distance explorations.

Should I incorporate interior baffles in the tank, since they are so long? What is a good outside coating for the tanks; or is that not recommended?

Are there any recommended fabricators or can I get a marine metal shop to weld them up? Or is the project going to be totally cost-prohibitive?

Stephen Williams · Posted: Sun May 30, 2010 8:50 am Post subject:

I don't think it would be cost prohibited. But, you may want to consider trim tabs. As you well know, the 16's are VERY weight sensitive, and unless you plan to draw from both tanks at the same time, you may have a little problem.

I think it was "Sea Beagle" who installed trim tabs and he really likes them. I've thought about it, as well, as I tire of shifting weight all the time!! Search for Sea Beagle's comments on this site to learn more.

Steve

seabeagle · Posted: Sun May 30, 2010 9:26 am Post subject:

More than the cost, I would wonder about the weight. I have three portables with 21 gallons max. Good cruising will get us 110 miles. You might need 40 gallons at that rate. Plus gear and people and you won't be moving fast at all.

seabeagle · Posted: Sun May 30, 2010 9:28 am Post subject:

As for trim tabs, they would help while moving. But not while standing still.

Alyssa Jean · Posted: Sun May 30, 2010 9:38 am Post subject:

Talk to Old Growth Dave, he took a 16 apart, added 2 feet and saddle tanks along and under the gunnels.

marco422 · Posted: Sun May 30, 2010 3:45 pm Post subject:

I carry a 12 and two 6's usually (24 gal) all in the stern, but I have no kicker. I also have a Permatrim and find the trim is pretty good. For my plans next summer in Haida Gwaii, I am going to need another 6 gal (160 nm journey) which is getting a little crowded in the splashwell along with the small inflatable across the stern. So I figured fixed saddle tanks might be a better longterm, especially looking forward to AK in two years. I've figured gear and passenger weights and should come in close to the 1150 max when fully loaded and the tanks would bring the weight forward more.

Reading old posts in this forum, I am starting to lean toward the "above-deck" type fill with an integrated fuel gauge since it would be closer to the center of the tank and read more accurately as the fuel sloshes around. Plus it is one less thing to go wrong (sending unit, gauges, fill tube, etc).

Regarding side-to-side weight distribution, is it kosher to draw from both tanks at the same time, or does that cause problems?

Bill Uffelman · Posted: Sun May 30, 2010 6:52 pm Post subject:

From Fluid Marine web site -- Tests performed on the 16' Cruiser, with the maximum legal load aboard (700 lbs)
****************************

You wrote:

I've figured gear and passenger weights and should come in close to the 1150 max when fully loaded and the tanks would bring the weight forward more.
****************************

Curious how you got an 1150 pound max weight capacity?

Bill Uffelman
Las Vegas NV

seabeagle · Posted: Sun May 30, 2010 8:34 pm Post subject:

1150 pounds: persons, motor, and gear. According to my sticker.

Bill Uffelman · Posted: Mon May 31, 2010 1:10 pm Post subject:

Classic case of "words matter" -- the 700 pounds are presumably people/dogs while the extra 450 is engine fuel, gear, etc.

Any way the CD 16 is a neat boat.

Bill Uffelman
Las Vegas

marco422 · Posted: Mon May 31, 2010 11:02 pm Post subject:

As already pointed out, the sticker says: 4 persons or 700 lbs; 55 max hp motor, 1150 lbs persons, motor, gear.

oldgrowth · Posted: Thu Jun 03, 2010 12:24 am Post subject:

marco – when I extended my 16 cruiser (C-Voyager), I built two saddle fuel tanks for the boat (not Coast Guard certified). Saddle tanks will help a great deal in balancing your load and increase your fuel capacity as well as freeing up space under the engine well. I believe it is one of the best modifications I made on my boat. The tanks will hold 22 gallons each filled to the brim but for all practical purposes 20 gallons is full. It gives me a range of over 200 miles. I generally run heavy (around 1650 to 1700 lbs) but then I am two feet longer than the standard 16 footer.

These two thumbnail show my tanks. Click on them for a larger view.

If you click on this thumbnail, you can see a black dot on the gunwale, that is where I put the fill cap.

This thumbnail when clicked on shows the dimensions of my tanks.

For the Marinaut I have custom saddle tanks made for the boat. Coast Equipment of Bellingham builds the tanks for me and they are Coast Guard approved. I am guessing they will cost between 475 and 575 dollars to have them build your tanks. In my opinion it would be worth it for the person wanting the extra range, extra cockpit space and improved handling.

Dave

www.tolandmarine.com

16Pounder · Posted: Thu Jun 03, 2010 10:28 am Post subject:

Marco

I see you live in BC so I'll pass this tip on to you. I have a 16' Angler and travel to Vancouver Island each summer to fish. I use a 7.5 gallon tank (plastic Tempo brand) at the stern. Last year during the ferry trip over I was called to the deck and told that my tank was against the regulations which allow no more than 25L (6.6 gal) for these types of fuel tanks on a boat. Since I was already on the ferry they told me they weren't going to do anything about it but if I was going to return with it that I would have to fill it with water. They also said that fuel tanks that were not installed by the factory whether fixed or not had to be less than 25L and the maximum number of tanks allowed are two.

So the bottom line is, if you use the BC Ferries, I think the saying "Out of sight and out of mind" would be good to follow. It would really suck to be in line at the terminal and have them tell you your tanks were against their regulations and that you couldn't board.

Al

Catch 22 · Posted: Thu Jun 03, 2010 10:51 pm Post subject:

I built saddle tanks for my 22 (pics in album), I powder coated them white, and yes I would definitely include baffles for strength and to keep fuel sloshing to a minimum. Make sure you rout your vent line well to prevent puddling in it. Also remember to ground the tanks and add a water separator. Just my two cents, let me know if you have any other questions...

marco422 · Posted: Sat Mar 19, 2011 11:46 pm Post subject:

Finally got my permanent tanks fabricated and installed (except for fuel line and gauge). They were welded by a shop in Vancouver for $1000 including fittings (yikes!) plus another $200 in miscellaneous hoses and hardware.

Pics are here: http://www.c-brats.com/modules.php?set_albumName=album1428&op=modload&name=gallery&file=index&include=view_album.php

Tanks are 10" high, 48" long, and 8 to 9-1/4" wide (tapered bottom to top) with nominal capacity of 63 litres (16-2/3 US gallons) each. So about 120 total litres (32 gallons) with expansion room. I installed Perko deck fills with integrated vents on each quarter in front of the cleats.

Installation was reasonably straightforward, except bending 1-1/2" fill hose is a bear! Tanks are supported by 1" tube welded on the outboard bottom edge and two support bolts shown in photos. I might still install inboard supports, but the tanks seem very solid already and I would prefer not to interfere with cleaning underneath. They have 2 baffles inside, integrated sending units and a nice tek top surface for a step.

All-in-all I'm pleased and can't wait to try them out on the first trip of the season to Princess Louisa on May long weekend.

rogerbum · Posted: Sat Mar 19, 2011 11:55 pm Post subject:

I assume you talked to Dave a bit about the design. One thing he did mention to me about the saddle tanks was that the baffle design was key. With the long tanks and a fill or vent at one end it's fairly easy to get the other end of the tank above the vent on a steep slope. This can lead to spillage when climbing or parking on hills with full tanks. With yours sitting on the floor, it looks like the fill/vent is quite a bit above the tank so this shouldn't be a problem.