How much gas over the winter?

There are two schools of thought... if the tank is full, there is less air space to condense and create water in the tank.   if you leave it empty, you have less bum gas to deal with in the spring.   I prefer to leave less in the tank since my boat is stored in the garage and there is not much condensation to worry about.   I also drain the fuel bowls on the carb and fog the cylinders.   It is always a bummer to put away the boat... I am glad you're taking care of it for the winter though.

I've had 15 years of experience (not an old timer by this site's standards, lol) with my pontoon boat, which has an I/O. It had a steel gas tank until I replaced it with a 50 gallon plastic tank about 5 years ago.

The boat is wrapped up / tied up in a large tarp (definitely not airtight) and left outside in the Wisconsin winter.

I always stabilize every drop of gas that goes into my boats. I also added lead substitute, but now it's getting hard to find.

Part of my winterization procedure is to fog the engine and then kill it with fogging oil. I use Marvel Mystery Oil. I choose to drain the block, manifold and riser and not use antifreeze (I'm talking about the Mercruiser 140, not the PCM 351W in the SN2001).

I have left the gas tank in just about every state... full, 3/4, 1/2, 1/4, one year it was almost empty. Honestly, it has never made a bit of difference in the Spring. It starts up, runs ragged until it burns out the fogging oil, then smooths right out. Then I change the spark plugs.

I never had a problem with the steel tank. It was 30+ years old when I took it out (it was too small for us).

Anyway, the theory about condensation blah blah blah makes sense, but I personally have never had any troubles whatsoever.

The bigger issue with leaving it outside is keeping critters out. We use many boxes of moth balls (individually wrapped in those meshes) and maybe a box of dryer sheets. One year we may have been a little short under one seat and we found a mouse nest with live babies in there. But they had done no harm. So we started doubling the amount of mothballs.

Steve

I store with whatever is left when I winterize it. That may be full that may be empty. No stabil ever. Always fires as soon as fuel hits the carb in the spring. My lay up is short by Indiana standards. Usually winterize sometime in October. Break it out again sometime in April. So 5-6 months. Never used Staybil in any sled I have owned. Always runs fine in the winter.

We Staybil every boat we winterize here at the shop. I am just one to see what I can and cannot get buy with.

Like Tim said, My preference if anything would be to leave 1/4 tank or so then fill it up on the way home from storage before you fire it so it has almost completely fresh fuel in the tank.

I know from what they taught us in Aviation school was that you should top off the tank (or close to) when you park the airplane for quite awhile due to the condensation building up in an empty tank. Water in your gas is never good in anything especially an airplane. You don't want the engine sucking up water on takeoff or just there after. Part of the preflight checklist is to drain the sumps (which are dump check valves in the wing locacted at the lowest point of the tank where water collects)

That being said even in our mild GA winters I but stabil in the fuel and top off the tank even though Miss Scarlett is kept in the garage. Their have been days when I walked out and the garage floor is wet with condensation after several days of cold soaking then a warm day blows in.
I've never had an issue starting her back up but the most down time she sees is about 2-3 months. We don't have the temps and hibernations that y'all do but to make a short story long........ I'd fill her up.

quinner wrote: All good info, even Donald, LOL.

Finally, QC is respecting me for my brains and not just my body.

BeeJay wrote: But now that Ethanol is being introduced to all our gas, this may start raising problems - time will tell, I guess.

Robert, our Wisconsin politicians told their lies and sold their ethanol scam many years ago, so southeastern Wisconsin has been stuck with that garbage for a long time now. I have a bunch of gas-powered stuff--lawn tractor, mowers, snowblowers, weed whackers, blower, etc--and my small engine mechanic friend finally really laid into me to stabilize all my gas (except for the cars). He was really tired of pulling my stuff apart to clean the deposits out of the carbs. I get my gas at Mobil, BP and sometimes Citgo in a pinch, so I doubt it's a brand issue. Once I started using Sta-Bil in everything, I never again had the problems I used to have. As a result, I've also stabilized every drop I put in the boats. My boats are not 2013 models and I never really know if the next trip might be the last for the season (like when I lost an I/O coupler and didn't have time to pull the engine that week). Stabilizer is sooooooooo cheap compared to the gas itself. If it ever gave me issues (some people claim they got red deposits with the old stuff; I've used the blue for years), I would think about it, but it's never caused any hassle and it avoids all those deposit issues, so it's a no brainer for me.

I can't find the CD2 Lead Substitute any more, just the expensive Gunk individual treatment bottles. So after some discussion in other threads here on CCF, I'm going to try Seafoam with no Sta-Bil and no other lead substitute. That is, the normal dose of Seafoam in every tank of gas all season long. Then I'll double up the dose for the winter. Seems like an expensive approach, though. We shall see. Any thoughts?

Steve

Boarderstad
   Advice well taken. Will kep my eye on potential problems. I never really noticed any Ethanol stickers on our pumps until recently, but they may have been adding that crap long before they posted it! Shortly after I bought my boat new in '97, correct craft issued a recall on gas hose replacement because of problems with that additve. My particular boat was one of the few that were immune to it because of a different manufacturers gas line was installed, and I never gave it much thought after that. Now that I am starting to hear horror stories from all angles I am becoming more concerned about it.In the past, my only concern about Gas/storage was the accumulated condensation in the tank hence the near fillup at layover.Darn, just one more headache this "hi-tech" world is giving us.

The gas companies put degradent in the gas so it will start to break down in about 90 days. They (oil companies) don't want you to stock pile gas. Aviation fuel doesn't have a degradent. I only run non-ethanol in my boats.

I got an interesting email from BOAT US regarding this topic and I thought I would pass it along to you guys that may have not seen it and also get some feedback from y'all. As mentioned above it's not too much an issue for us who put the boats to sleep for only a couple months but those of you who put your CC's in hibernation for 6 months it is....Thoughts?




The Ethanol Debate


Ever since E10 (a gasoline blend with 10 percent ethanol) became widespread, there have been two schools of thought when it comes to winterizing your boat: Keep the tank full, or empty it completely.

Both sides agree on the basic facts. Ethanol is hydrophilic — it attracts and holds water. Small amounts of water will be burned in the combustion cycle, but ethanol can only absorb so much water. When it becomes completely saturated, phase separation occurs, and the corrosive ethanol-water mixture sinks to the bottom of the tank. If the engine is run, this mixture can damage seals, O-rings, injectors, and other delicate engine parts. The upper "gasoline" layer will be depleted of ethanol and have a reduced octane level, which can also cause engine problems. If a tank is left partially full, there is more room in the tank, which means more surface area for condensation formation and less ethanol to absorb the resulting water. Cycling temperatures from warm to cold also increases the amount of condensation. Finally, ethanol cannot absorb as much water at low temperatures as it can when it's warmer, so the gasoline will phase separate more quickly in colder temperatures.

The obvious answer is to completely empty the tank — and even the fuel lines and filters if possible. But any boat owner with a gas tank capacity of more than a few gallons will tell you how problematic it is to completely drain it, and some indoor storage facilities don't allow empty tanks because they may contain volatile fumes (usually there is an exception for portable tanks that are empty and uncapped). USCG regulations prohibit drain valves on the bottom of a gas tank (imagine what would happen if one corroded through or broke off, leaving a bilge full of gasoline) so the only way to remove gas from a large tank is by pumping it out. Too many of our claim files prove that using something like a shop vac to do the job will land you in the hospital. Finding ignition-protected equipment and transporting and disposing of the gas afterward is simply not practical for the average boat owner.

That's why Seaworthy has always been in the keep-it-full camp. We are, after all, boat owners, so we're forced to take our own advice. If it's impractical or impossible to empty the tank completely, then keeping it full should make it more difficult for enough water to get into the fuel to cause problems. But just in case we missed something, we asked some industry experts for their thoughts on the subject.

Bob Popiel, head of marine service at Yamaha, said his preference is complete draining of the fuel system including tank, fuel lines, carburetor bowls, and the vapor separator tank (VST). VSTs, he says, can hold a cup of fuel and they're vented to the atmosphere, as are carburetor bowls. The VST has a drain, but it is hard to access for a typical owner, while on older engines, carburetor bowls have drains that most people can get to, he says. Draining the system is even more important on older engines (10-15 years old) because they don't have the same ethanol-resistant parts that new engines do. That said, Popiel knows that draining the whole fuel system is often difficult, so another option is to simply disconnect the fuel supply and let the engine run out of fuel, which will at least drain most of the gas from the VST or float bowls. If you choose not to drain the system, he recommends adding a good quality stabilizer to fuel, topping up the tank, and running the engine enough to get fuel all the way through the system. Ten minutes ought to do it, he says.

John McKnight, director of environmental and safety compliance with the National Marine Manufacturers Association, says, if you're storing gasoline for two months or more, try to drain the tank if possible. If it's not practical, add stabilizer, fill the tank, and run the engine for 10 minutes to allow the treated gasoline to get into the fuel system.

Mercury Marine says that if it is difficult or not possible to remove the fuel, maintain a full tank of fuel with a fuel stabilizer added to provide fuel stability and corrosion protection. Top off the tank until it's full to reduce the amount of exchange with the air that might bring in condensation, don't cap the tank vent, and don't fill with fuel to the point of overflowing so there is some extra space in the tank to allow for fuel expansion and contraction with temperature changes.

So there you have it. If you can empty your tank — and entire fuel system — for the winter and your storage facility allows it, then do it. But where that's impractical, keep the tank full, add a stabilizer, run the engine for 10 minutes, and sleep well.

I plan on running our boat at least once or twice a month during our short down time. I will probably run it on the lake for a bit, then fill it up with fresh gas before the next run.

I'm a rookie with boats, but this has worked great for my jetskis for the past 10 years. Don't see why it wouldn't work in a boat.

AAM196 wrote: Full tank with stabil... easy

I have had zero luck with sta-bil keeping fuel fresh over the winter. I do not notice any difference with no stabilizer at all.

No ethanol free gas around here that I can find- though 100LL (avgas) might be an option. But its expensive and a pain to bring the boat to the airport that sells it(not to mention 4 boats ).

AAM196 wrote: TRBenj wrote: AAM196 wrote: Full tank with stabil... easy I have had zero luck with sta-bil keeping fuel fresh over the winter. I do not notice any difference with no stabilizer at all. No ethanol free gas around here that I can find- though 100LL (avgas) might be an option. But its expensive and a pain to bring the boat to the airport that sells it(not to mention 4 boats ). Stabil marine works.. it says so right on the bottle.

AAM196 wrote: Full tank with stabil... easy

Well, you didn't sat "marine" in your first post!!
I've used the Marine version for a couple of years. Still not the best!!

So how did you determine gas went bad.... taste? Boat ran bad.

Ethanol suxs. Either way, the gt40 don't care...just goes.

To much corn gives me bad gas too.