Extended Summer Layup in Florida - Fuel and Water Tanks

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BroadCove

Veteran Member
Joined
Oct 1, 2019
Messages
84
Location
United States
Vessel Name
Say Goodbye
Vessel Make
Grand Banks 47 Eastbay FB
As boating goes, our plan to return our boat to the Cheasapeake has changed, and we're now leaving the boat in Florida for 5-6 months. We're having a good bit of work done, and once that's complete the boat will stay on the hard until we return to Florida this fall.

My question is with regard to fuel and water tankage. I read elsewhere to fill them, because the additional weight low in the boat adds stability if (when) there is a big storm. On the other hand: 1) it's also more pressure on the hull where the stands are due to the additional weight; 2) at current prices, I not thrilled about purchasing 500 gallons of fuel (although who knows, maybe in six months I'll wish I had).

Like many things in boating, I know there's not necessarily a "right" answer here. But I'm interested in feedback from others who have had their boats laid up for an extended period in warm weather...tanks full, empty, or somewhere in between?
 
For just a few months in warm weather, I wouldn't worry about the fuel tanks. Just leave them wherever they are. For the water tanks, you want to try to keep junk from growing while unattended. Personally, I'd fill the water tanks and add a little extra bleach (only a little bit though) beyond what's in the city water. Run that through all of the lines, top off the tank to minimize air exchange (and resulting stuff getting in).



When you get back to the boat, I'd plan to drain the water tanks, flush things out a bit and then do a bleach shock on the whole system.
 
We’ve always gone on the hard lite on liquids. Not empty but we would dump some water and never hauled with full diesel tanks. Our Krogen 42 held 700 gallons of fuel and 360 gallons of water. The liquids weigh out at over 7.5k lbs. I was always afraid of supporting that much weight on jack stands.
 
For what it's worth in terms of supporting weight, for those of us in cold climates, it's pretty typical to haul out for the winter with no water, but full fuel. As long as the boat is well supported, it shouldn't be an issue for most hulls.
 
Since you will be on the hard through the gut of hurricane season, I would put some mobile home type screw anchors in around the four "corners" of the boat an secure heavy mooring lines to them. You will likely have little choice about who the yard moves in and out around you during the season unless they perhaps have a long-term storage area. If so, try to not be set down near a sailboat which tend to blow over before the power boats do. I live close to the local yard which was incapacitated for a long time after Hurricane Michael while the insurance companies untangled all the policy issues with sailboats having toppled over onto powerboats. Not that you have any control over the issue, but my personal feeling is that I would never haul for a storm. I have dodged many, many hurricanes here since 1990 with both my Grand Banks and this Mainship I have both moored securely.
 
Don't forget the sanitation system!

TOILET(S)
If your toilet(s) use sea water, disconnect the intake line from its thru-hull and run a bucket of clean FRESH water to which you've added a quart of distilled white vinegar through it to rinse ALL the sea water out of the intake line, pump, channel in the rim of the bowl and the discharge line.

If your toilet uses pressurized fresh water you can just flush a couple of cupfuls of distilled white vinegar through it, followed by a gallon of clean fresh water after 45-60 minutes (VERY important step) to rinse out the discharge line and call it done.

HOLDING TANK
Pump out and THOROUGHLY rinse out the holding tank...not as hard as it sounds:
Put about 6" of water into the tank VIA THE DECK PUMPOUT FITTING 'cuz that sends the water into the tank at the bottom to stir up any sludge. Pump that out. Repeat, repeat, till you're pumping out clean water. If you have an overboard macerator pump, add another couple of gallons of water and run the macerator to rinse it and its related plumbing out. (Btw, this should be done 2-3 x/year as routine tank maintenance.)

If you have a Type I MSD (onboard treatment device--LectraSan, ElectroScan or PuraSan), follow mfrs instructions for extended layup.

--Peggie
 
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Thanks all for the feedback. Confirms where I was heading...leave fuel tank as is, fill & add a bit of bleach to fresh water tank, and pump out / clean / pump out black water tank. (Thanks, Peggy, have your book, regular use of no-flex, and regularly add fresh water via pump out fitting to clean out the tank.) Fingers crossed for a quiet named storm season...
 
Plug your through hull discharges. Mud wasps and other creatures love to build nests in bilge pump and air conditioning discharges, holding tank vents, and other unscreened ports. Push some fiberglass screen material into each discharge port to keep them out. Consider other openings on an individual basis.

Ted
 
We store out of the water over the winter in Washington and leave fuel tanks full to minimize condensation. I think you got a good suggestion to add a bit of CL to the water tanks, we have to purge our system due to freezing but that definitely won't be your problem.

One watch point hot climates. A friend of mine stored his 42' trawler out of the water in Mazatlán one summer and had damage due to excessive heat buildup in the boat (it reached something like 150F in the boat!). I'd guess heat is an issue in FL as well. Locals no doubt know what is the best approach to manage it.
 
Have some way to vent the interior without letting the bugs in. Take things like candles out of the boat, they may melt.
 
We’ve left our boat in Florida for 6 summers, in the water though. The only heat related issue we had was for 2 years in a row we had a spray can of CRC Rust Inhibitor discharge. What a mess! We had other spray cans that were fine.

Something to check when you haul out is the level of the boat. We had friends that came back to a wet moldy mess when the yard had blocked their boat with the bow down slightly. It wasn’t much but on 44 footer, water collected and ran down the companion way stairs.
 
Thanks all for the tips! Very helpful. (Re: blocking with the bow too low, we looked at a Vicem that was blocked bow down for two years, rain water came through a bow hatch and then through a crack in the anchor locker sole, and the wood in the hull rotted...an entire section of the starboard bow had to be removed and rebuilt.)
 
My question is with regard to fuel and water tankage. I read elsewhere to fill them, because the additional weight low in the boat adds stability if (when) there is a big storm. On the other hand:

1) it's also more pressure on the hull where the stands are due to the additional weight;

2) at current prices, I not thrilled about purchasing 500 gallons of fuel (although who knows, maybe in six months I'll wish I had).

It's a 42,000lb boat. 1,200lbs of water is not going to make a difference.

Full fuel tanks don't rain condensation into the fuel from the humid summer air in florida. Put in plenty of stabilizer, anti-fungal and some startron then fill them to 90%. The warm air will cause the fuel to expand.
 
In the tropics when not on the boat for any length of time used a product called Bop. An Insecticide. Take rags and spray liberally before inserting in thru hulls. Also wrap around dock lines if in the water or tie downs covered with Saran Wrap when on land. Buy a cheap home air conditioner and place over a hatch to kept humidity down. Finally a sun cover and take hose off lowest thru hull in the boat if on the hard. Would also look into seeing if there’s yacht management in the yard you’re using. Someone to check everything out every few weeks and before/after storms. Don’t know what boat monitoring systems you have. If none yacht management can also check your batteries. We had solar so they were fine even when not plugged in to shore power for weeks.
Our habit is full fuel tanks and use biobor and totally empty water/sewage systems except for using 100 potable antifreeze. If you use undiluted 100 it’s cidal and unlike beach no risk of any damage. Trick is to totally drain water heater before starting and a good flushing of sewage system. Also pour some into a bone dry blige and nothing will grow. Been impressed that fogging the boat before locking up with mold/mildew killer is worth it if your not going to use yacht management. Mold is miserable in the tropics. Expect the same in Q tip land.
 
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For just a few months in warm weather, I wouldn't worry about the fuel tanks. Just leave them wherever they are. For the water tanks, you want to try to keep junk from growing while unattended. Personally, I'd fill the water tanks and add a little extra bleach (only a little bit though) beyond what's in the city water. Run that through all of the lines, top off the tank to minimize air exchange (and resulting stuff getting in).



When you get back to the boat, I'd plan to drain the water tanks, flush things out a bit and then do a bleach shock on the whole system.


I usually put some baking soda in the water tanks also. It seems to help kill any bad smell and taste.
 
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