posted 04-09-2011 04:47 PM ET (US)         

Also, on a classic, can [the Moeller white 24-gallon on-deck fuel tank] be installed so that the existing fuel line opening can be used, or must a new hole be drilled into the rigging tunnel?

posted 04-10-2011 02:08 AM ET (US)            

Right now, my boat is ALL deck space. No tanks or batteries on the deck as described, AND no seats either. Not even the switchback thwart seat. Makes the little Montauk seem huge and clean and simple, even if having the weight forward costs me some speed.

posted 04-10-2011 09:19 AM ET (US)            

The REFERENCE article (linked above) shows many solutions for on-deck fuel tanks, although please ignore its references to Pate Plastics and Tempo, as both manufacturers are no longer in the business of making fuel tanks. The article has links to other articles on this topic.

Your choice for an on-deck fuel tank will be influenced by the type of engine you are using and your boating. If you have a modern engine with excellent fuel efficiency and your boating does not require long passages to be made, you may find that you do not need to carry a large quantity of fuel. Suggestions to carry 24-gallons of fuel may not be appropriate for your use. For example. if you have a modern engine, perhaps a Yamaha F70 four-cycle engine, and you don't run around at full throttle all day, the average fuel flow rate could be only a gallon per hour. A 24-gallon fuel capacity might give you enough fuel capacity for a month of boating!

posted 04-10-2011 11:06 AM ET (US)            

Plastic Disadvantages: If you EVER have a fire in the boat the plastic will melt and release the fuel into the hull. Second is that they eventually degrade with UV and need to be replaced.

Aluminum Advantages: See fire (above) and UV sensitivity (above). Can be constructed in any size/configuration as needed.

Aluminum disadvantage: Must be custom made, much more expensive.

Single tank v/s multiple tank:

Single tank: What's there to say? It's one tank. Pick one tha fits your needs.

Multiple tanks: Allows fuel to be segregated, IE: contaminate one tank with water and you have a second "fresh" source. Allows "first in, first burned" fuelling (IE burn the oldest fuel first). Gives excellent situational awareness as to fuel level (IE: If you switch tanks before the first one is empty, there's a darned good chance you can get back to the dock on what remains).

My choice is one aluminum tank of what would normally be 28 gallons capacity under the RPS. BUT I had it made with a partition internally, two fillers, and two pickups. It's "two tanks in one structure". Three way ball valve to switch between the cells. Allows me to fill one or both, and manage fuel as above. Likely influenced by my aircraft experience where that is really the only way things are done.

Just one of many good ways. Much depends on the environment you use the boat in. The tougher the water, the more robust the system needs to be. One 12 gallon under the console offers a lot of advantages for certain uses (man, I would LOVE an absolutely empty Montauk) ... but maybe not for another areas where 100 miles of running is the norm. On a lake having one tank is fine... 20 miles offshore I really like having a second completely independant fuel source.

Dave

posted 04-10-2011 01:37 PM ET (US)            

Boston Whaler supplied the tank mats that these tanks would fit as standard equipment int he Montauk.

It is not true that there were no aluminum 12 gallon fuel tanks made for the Montauk. In 1986 MIRAX started manufacturing their 12 gallon Whaler tanks out of aluminum.

These tanks have proven to be much more durable than the steel tanks. Many of them are still in use today. You can still buy these tanks (with some subtle differences) but they are not a low cost option.

http://www.miraxfuelproducts.com/

posted 04-10-2011 04:57 PM ET (US)            

- You can manage the lateral weight distribution with twin tanks. Most small boats will tend to list to port and with twin 12 gallon tanks you can use the port tank first to help compensate for that. If you happen to have your boat loaded such that it reverses this listing tendency, you can reverse the order of which tank is used first.

- When one tank runs dry, you know you have used exactly half your fuel capacity left.

- Twin tanks allows space between them for the fuel hose to enter the rigging tunnel. Montauks came for the factory with a hawse hole under the RPS that is covered by single large tanks forcing a new hole to be cut further aft with the hose exposed and in the way of your heels when seated, facing aft.

- While not exactly portable, you can (and I have, many, many times) lift a 12 gallon tank out of the boat and take it, by itself, to the gas station for filling. You can also easily remove them from the boat for cleaning.

posted 04-10-2011 07:37 PM ET (US)            

http://www.amazon.com/Moeller-Marine-Product-24-Gallon-Topside/dp/ B002UZJRW0

I have had it for all of last season, and it replaced a red 26 gallon Moeller, which in turn replaced two red twelve gallon OEM Yamaha tanks.

The fill-up is tilted slightly forward, which makes it fit ideally under the Montauk's RPS.

posted 04-10-2011 07:58 PM ET (US)         

Does the Moeller white completely cover the existing fuel line hole, requiring a new hole to be drilled further aft?

This would be the biggest drawback for a single large tank in my opinion, if it had a small channel or perhaps if the tank where raised off the deck a 1/2" the might allow the existing hole to be used.

posted 04-12-2011 05:19 AM ET (US)            

The new white tank covers up some of the hole to the rigging tunnel, but not all. I drilled nothing. I also put in a few starboard blocks to keep the tank from sliding around. I'll try to get a picture this Saturday, as I will work on the boat after I run the Asbury Park Half.

posted 04-12-2011 08:47 AM ET (US)            

I'm only worried about things that happen at sea, bearing in mind that we rouiutinely have a foot+ of water in the Montauk. Having two segregated fuel cells just keeps one more ace in the hole. Bear in mind that yet again, this brings us back to the "T t's wghat works for ONE GUY BEST in ONE ENVIRONMENT" that's best. My best might be huge overkill for someone else, and someone elses 6 gallon tank in the console might be fine for him and laughable for me.

Tom's suggestions about the pair of Mirax tanks is a good one, two 12 gallon aluminum tanks does pretty much do it all. I think if I did my boat over I'd take his advice.

>The only advantage of a plastic tank is?

Available on demand at any boat store? That's about it.

Dave

posted 04-12-2011 02:09 PM ET (US)            

Dave

posted 04-12-2011 05:19 PM ET (US)         

Sal also has some pictures of his in that thread and that one is more confusing. The hole looks like the factory hawse hole but it appears the fuel tank is far enough forward to expose the back of the hole or the hole is actually further aft on that boat.

compare: http://continuouswave.com/whaler/reference/images/ RS3-oldOMCTanks492x338.jpeg

and

posted 04-12-2011 08:23 PM ET (US)            

http://i123.photobucket.com/albums/o295/TheMaryAlice/whalerpics/moeller. jpg

Dave

posted 04-13-2011 02:26 PM ET (US)            

If, however, the factory positioning of the fuel tank is used, the factory hawse hole will be covered.

The fuel tank mats were always installed so the forward edge was aligned with the forward end of the Z-leg bases. The hawse hole was cut into the floor so it would lie fully forward of the aft ends of the fuel tank mats.

If you can tolerate the fuel tank sitting forward a bit, you can use the factory hawse hole.

posted 04-13-2011 02:38 PM ET (US)            

http://i123.photobucket.com/albums/o295/TheMaryAlice/whalerpics/moeller. jpg

...with...

http://www.flickr.com/photos/saphot/5617055310/in/set-72157626491353484

Dave's fuel tank position in his Montauk (which looks like a post-1990 Montauk, not a 1987) has the tank cheated forward about two inches and even at that, half the hawse hole is covered by the tank, whereas beemerfan's tank sits on the factory fuel mats and an additional hole has been drilled in the floor to accommodate the fuel hose.

posted 04-13-2011 02:51 PM ET (US)            

My comment was intended to say that my 1987 Montauk has the tunnel in exactly the same spot as the boat in the linked photo, and that the Moeller tank sat in the original whaler tank pads, with the inside lips of the pads cut off with a razor knife so the single tank would fit into the original space. There was no problem with running the hose thru the hose-tunnel whatsoever, and the tank was not "cheated" forward.

Perhaps there are variations in the hose tunnel position? I've always scratched my head when guys say that the larger single tanks will not rig the hoses thru the tunnel. This has not been my experience.

Dave

posted 04-13-2011 03:34 PM ET (US)            

Let me see what I can dredge out, boat is still covered for the winter. Think I have a pic someplace here on the computer with the Moeller installed though. Who can host the pic since I don't have a Flickr account and don't want one? The pic will look exactly like the one linked, save foe the teak RPS. The oval fuel line rigging hole is 'mostly' covered but has about an inch exposed, which is plenty of space for the hose.

Dave

posted 04-13-2011 05:50 PM ET (US)            

This is after he and I installed the new tank.

[IMG]http://i134.photobucket.com/albums/q115/swr540/Montaukfueltank3.jpg[/IMG]