Green Gas For Boats: Good Or Bad Idea?

Green gas is a topic of discussion among boat owners, with some reporting mysterious cases of their boat gas turning green. While the cause of this discolouration remains unclear, it is important to address this issue as it may indicate a potential problem with the boat's fuel system. In one instance, a boat owner discovered that the gas in their primer bulb appeared dark green, resembling 2-stroke oil. Despite their confusion, as they had never added 2-stroke oil to the gas tank, they were advised by a mechanic to dilute the green gas with fresh gas and continue using it without causing harm to the engine. This advice, however, sparked a debate among other boat enthusiasts, with some suggesting alternative causes such as decaying gas lines or gaskets, and others speculating about the source of the fuel and potential mix-ups at the fuel dock.

Green gas mystery: Why was the gas green?

A boat owner was puzzled by the green colour of the gas in their boat's tank. They had not put any 2-stroke oil in the gas tank and no one else had worked on the boat. The boat was kept under a mooring cover, making it unlikely that someone else had tampered with the gas tank. The fuel dock from where the gas was purchased did not put any additives that could have resulted in the green colour. So, what could have caused the gas to turn green?

One theory suggested that the green colour could be due to algae in the gas tank. However, this seemed unlikely as algae require water to grow, and no water was found in the fuel sample. Another possibility was that the green colour was caused by a decaying rubber gasket or gas line. The boat owner also considered the possibility of old gas, but dismissed it as the gas had been purchased recently.

After some investigation, the boat owner discovered that the green colour was likely caused by 2-stroke oil leaking from the remote oil tank located under the console. The oil system was pressurised for extended periods even after the engine was shut down, indicating a possible defective crankcase check valve. The boat owner planned to test this theory by cracking open the cap on the remote oil tank to check for persistent pressure in the system.

In conclusion, the mystery of the green gas was likely caused by 2-stroke oil leaking from the remote oil tank due to a faulty check valve. While the exact cause was not definitively proven, the boat owner's diligent investigation and troubleshooting narrowed it down to the most probable explanation. This case highlights the importance of regular maintenance and attention to small details when dealing with boats and their intricate systems.

Gas safety cans: What colour should a gas can be?

Gas safety cans are designed to prevent accidents and injuries resulting from the use and storage of flammable liquids. They are available in green, yellow, blue, and red, with each colour indicating the type of liquid the can is designed to store. While the colour-coding system enhances user safety by eliminating confusion over a can's contents, choosing the wrong colour can have dangerous consequences.

Green safety cans are designed to contain oils. By "oils," the regulations refer to any kind of mixed oils that are flammable. When storing oils in green safety cans, it is important to follow basic safety precautions and store them outside of your home and away from anything that could ignite. Even though oils are harder to ignite than other flammable liquids, they will burn hot and vigorously once ignited.

Red safety cans are designed to store gasoline, the most common residential flammable liquid due to its use in lawn mowers and other lawn equipment. It is also the most dangerous. Gasoline should always be stored in a red can and never in milk containers, glass bottles, antifreeze jugs, or any other container that does not meet EPA or DOT requirements. When hauling gasoline, secure it in your vehicle to prevent slipping, and unload it immediately upon reaching your destination. Avoid storing gasoline in your basement, as it could ignite and cause significant fire damage to your home. Instead, consider purchasing a flammable storage cabinet to store gas cans. Gasoline has a relatively short shelf life and should not be used if it is between 6-12 months old. If you plan to store gasoline for more than a year, consider adding a fuel stabilizer, which can extend its shelf life by several years.

Yellow safety cans are designed to store diesel fuel, which is highly flammable and should be stored at roughly 70 degrees Fahrenheit, with no exposure to oxygen. Avoid storing diesel in your garage or house, and elevate the can on a surface above the ground to prevent rust. Water is an enemy to diesel, and condensation inside a diesel can or fuel tank will cause bacteria to grow and degrade the fuel. Constantly monitor for condensation and use biocide additives to prevent bacteria caused by water. Keeping the tank or can full will also help reduce water buildup.

Blue safety cans are designed to store kerosene, a less volatile flammable liquid than gasoline or diesel. Kerosene safety cans should follow the same safety guidelines as those for gasoline and diesel, and they should hold no more than 5 gallons. Kerosene is among the easiest flammable liquids to store as it does not evaporate or freeze like gasoline. Be sure to store kerosene in a clean container, as contaminating it with dirt or dust can make it thick and unusable. If using kerosene for residential purposes, consider storing it in an outdoor shed rather than in an attached garage, as it is still a flammable liquid.

Gas contamination: What was the cause of the contamination?

Gas contamination can be a serious issue for boat owners, and in some cases, the cause of the contamination may be a mystery. In one case, a boat owner discovered that the gas in their tank appeared to be dark green and would not start. After some investigation, it was found that the green colour was likely due to the presence of 2-stroke oil in the gas, which had made it difficult for the engine to start. While the owner had never put 2-stroke oil in the gas tank, it was suspected that there may have been a backflow of oil through the engine or a problem with the fuel dock supplying contaminated gas.

One potential cause of the contamination was the fuel dock supplying gas that was already contaminated. The owner of the fuel dock denied this, stating that their gas was slightly brown-orange in colour and that no one else had reported any issues. Additionally, they claimed that they did not sell premixed gas and that their system would shut down if any water was present. However, the owner of the boat insisted that the fuel dock was the source of the contamination, as it was the only place they had ever filled up.

Another potential cause considered was the possibility of a defective crankcase check valve, which could have allowed pressurised oil to seep back through the engine and into the gas tank. This was supported by the observation that there was also oil leaking from a hose on the remote oil tank, indicating that the oil system was staying pressurised even after the engine was shut down. A Mercury mechanic explained that a defective crankcase valve could lead to persistently high pressure in the oil system, potentially causing oil to seep through the oil pump after shutdown.

While the definitive cause of the contamination remained unclear, the boat owner was able to resolve the issue by draining the contaminated gas and refilling with fresh fuel. This highlights the importance of proper fuel handling and storage, as well as regular maintenance and inspection of boat engines to prevent similar issues from occurring.

Gas dilution: Is dilution a good solution?

Gas dilution is a viable solution to rectify issues with boat gas. Dilution can be an effective approach to resolve problems with contaminated or substandard boat gas. In the context of a boat owner's experience, green-coloured gas was observed in the fuel tank, leading to concerns about its origin and potential impact on engine performance.

The boat owner sought advice from a Mercury dealer, who attributed the green colour to 2-stroke oil and suggested diluting it with fresh gas as a viable solution. This approach is supported by the observation that 2-stroke oil is typically pre-mixed with gas, and diluting it would reduce its concentration. However, the boat owner was puzzled by the presence of the oil, as they had never added it to the gas tank themselves.

Dilution can be a practical solution in such situations, as it reduces the concentration of the contaminant and may prevent it from causing significant harm to the engine. In this case, the dealer's suggestion to dilute the green gas with fresh gas and use it is reasonable, especially considering the large tank size of approximately 100 gallons. Diluting the contaminated gas can help avoid the tedious and challenging task of completely draining the tank.

However, it is essential to identify the source of the contamination to prevent recurrence. In this case, the boat owner explored various possibilities, including algae growth, rubber gasket decay, and fuel dock mix-ups. They also considered the potential for backflow of 2-stroke oil through the engine, which could be addressed by replacing the crankcase check valve and primer bulb.

While dilution can be a temporary fix, it is crucial to investigate and address the root cause to ensure the issue does not persist. Additionally, it is important to note that dilution may not always be the best solution for all types of contaminants or issues with boat gas. In some cases, completely draining the tank and refilling with fresh gas may be necessary to ensure optimal engine performance and safety.

In conclusion, gas dilution can be a reasonable solution for certain issues with boat gas, such as contamination by small amounts of 2-stroke oil. However, it should be accompanied by proactive measures to prevent recurrence and comprehensive root cause analysis. Boat owners should also remain vigilant and consult experts when in doubt to ensure their safety and the proper functioning of their vessels.

Gas disposal: How to dispose of contaminated gas?

Green gas in a boat tank can be a mystery, and while it may not be harmful to the engine to run it, it is important to identify the cause and drain the tank if necessary. Now, onto the topic of gas disposal.

Gasoline is a hazardous product and must be disposed of properly. It is illegal to pour it down the drain, throw it into the trash, or use it as a weed killer. The proper way to dispose of contaminated gasoline is to follow these steps:

• Put the gasoline in a government-approved container, typically an approved safety can labeled "gasoline" with a capacity of 5 gallons or less.
• Find a local disposal site by contacting your county or city waste management.
• Dispose of the bad gasoline at an approved disposal site, which may include hazardous waste collection sites or community disposal events.

Alternatively, you can mix contaminated gasoline with good gasoline and use it in your car or small engine, as cars are better at burning bad gasoline than small engines. However, it is important to ensure that no water or debris makes its way into the mixture, as this could cause bigger issues.

If you are dealing with contaminated gasoline in a small engine, such as a lawnmower, here are the steps to follow:

• Drain the old gasoline by detaching the gas line below the fuel tank and allowing it to drain into a gas storage tank.
• Drain the carburetor if it is easily accessible, and clean it with good gasoline or rubbing alcohol to remove any water or residue.
• Reattach the carburetor and fuel line, then add a small amount of good gasoline.
• If the engine still won't start, add a small amount of rubbing alcohol to the fuel to increase volatility and address any remaining water issues.

Remember, when handling and storing gasoline, always prioritise safety. Gasoline is highly flammable and can be explosive. Store it in approved, air-tight containers, away from children, pets, open flames, and sources of ignition.

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