Do you fill your fuel tank during storage?

JWS

Crew Member
Do you keep your fuel tank full over the winter to prevent/minimize condensation buildup or are you just relying on fuel stabilizer?
 
full tank + stabilizer for 2-3 months and then take her out on the water from mid Jan whenever it's calm and nice out there. Adding a can of seafoam every time I fill her up also helps.
 
drain mine. burn it in the cars.
i have a gastapper -- plugs into the boat dash, drains the fuel in minutes.
 
I did all of the above.Filled it and added stabil and seafoam.Then drilled a hole through a bulkhead for bilge and hit the fuel tank,it was emptying in a hurry so I stuffed a rag in the hole to slow it down as it filled the bilge.Ran to Sherwood and Barry gave me a 45 Gal. tank and I emptied the tank.Remove tank cover,fwd.bulkhead,foam ,tank,more foam.Now have new stringers in to support tank,will have tank repaired and reinstalled with no foam this time. Just my regular winter routine,GGRRRR.
 
When winterizing I fill it full and add fuel stabilizer, octane booster and some methyl hydrate. Run it for a while and check the fuel separator for any water then check it again when I run it again in the spring. Done it for years, works well.
 
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Half tank with stabiliser added, add fresh in the spring to dilute any issues. Dry-ish Okanagan though, less condensation.
 
I’ve heard from an experienced mechanic there’s no need to fill the tank. But stabilizer is essential.
 
I have both an on deck tank and below deck tank. The on deck tank collects water, albeit slowly. Took ~ 1/2L out this season after 6 years. I assume from condensation. The below deck tank doesn't have the same issue. Figure I'll probably just pump any accumulated water out every few years and try to keep the tank full.

Fuel stabilizer won't do anything for condensation. It can be important, but not water related. My kicker (2017 merc 9.9) hardly runs if I don't get stabilizer in it at the end of the season. Have to clean the carb to get it running properly the next year.
 
I’ve heard from an experienced mechanic there’s no need to fill the tank. But stabilizer is essential.
No need to fill, but what if its mostly empty? Which is how I have left mine so far this winter, first with this new to me boat. Had motors fogged and winterized, and fuel stabilizer is in the tank but tank is probably 1/4 full at most currently. Partly because I intend to redo my bilge pumps and hoses this winter, and I will need to pull my tank to do so.
 
No need to fill, but what if its mostly empty? Which is how I have left mine so far this winter, first with this new to me boat. Had motors fogged and winterized, and fuel stabilizer is in the tank but tank is probably 1/4 full at most currently. Partly because I intend to redo my bilge pumps and hoses this winter, and I will need to pull my tank to do so.
I leave mine at 1/4 of a tank usually.
 
Suppliers say gasoline is fine in the tank for up to six months. I don't have my boat stored that long. Condensation in the tank can only occur if there is an air exchange. At stable, indoor winter storage temperatures, that is minimal or zero if you tape over the tank vent. Just remove the tape before launching.

Fogging the engine is likely worthwhile before an extended storage. You could also run a 2 stroke mix for a few minutes into a 4 stroke engine for added cylinder protection.
 
I never worry about filling it. Get the proper amount of stabilizer in and keep a vigil watch on the racors the first few times our in the spring for water from condensation
 
I never worry about filling it. Get the proper amount of stabilizer in and keep a vigil watch on the racors the first few times our in the spring for water from condensation

What are you using for stabilizer? Stabil? I usually don't to anything much at all either as I run the boat often during winter but at the same time, stabilizer seems logical to me. I had my tank "polished" dockside this season and they inspected it, said it was super clean and not much junk inside at all. Clearly, nothing to do with my diligence haha
 
I run seafoam in almost every tank of fuel. I never know when my boat might sit for months.
 
What are you using for stabilizer? Stabil? I usually don't to anything much at all either as I run the boat often during winter but at the same time, stabilizer seems logical to me. I had my tank "polished" dockside this season and they inspected it, said it was super clean and not much junk inside at all. Clearly, nothing to do with my diligence haha
Pretty sure that’s the stuff. Previously I used the Quicksilver brand for over 30 years as that’s all that was available over there
 
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