I would just like to inject an experience I had related to the safety of gas versus diesel. This happened to me in 1980 aboard a 1960 Trojan cabin cruiser I owned at the time. It was my first of 4 boats. I also want to be upfront here stating the situation could just have easily turned out far worse and in fact fatal.
That boat had twin 50 gallon gas tanks and I had just filled up both of them. I had also just had a mechanic friend of mine replace the fuel hoses from the tanks up to the fuel pump and to the carburetor. In doing the work he made several mistakes. The first mistake was taking both feed lines from the tanks and connecting then via a common tee fitting that was suspended amidships under the cockpit sole without the aid of proper straps to hold the weight of the fuel lines and fitting.
The brass tee connector needed 3 hose clamps minimum to secure the three rubber hose lines, two going in and one going out. He only had two hose clamps of the proper size and his thought was he would come back in a week or two and add the missing clamp. When I saw him the day after he did the work he advised me of the condition. Remarkably, I didn't think it would be a problem. Huge mistake on both our parts.
Two weeks later I went to the boat and as I was walking down the dock I could smell gas. It turns out Murphy had paid a visit to my boat shortly before I got there. It was a 'worst case' scenario. It turned out that the one rubber fuel line without the hose clamp on it possibly swelled from being exposed to the fuel, and what was a 'tight fit' according to the mechanic became a loose fit and the hose came off of the tee fitting. This, in turn, caused the unsupported tee fitting to fall into the bowels of the bilge.
To make matters worse, both shut-off valves on the tanks had been left open by the mechanic when he tested the system by running the engine. I never left the boat without closing those off, and trust me, over the next 18 years of owning boats I never left a boat without shutting those tank valves off. When the tee fitting dropped down it fell below the bottom of the tanks and siphoned the 50 gallons of gas in the still connected starboard tank into the bilge. Hence the smell of gas as I neared my slip.
When I opened the hatches in the cockpit I could see the bilge was full of gas. I rapped the side of the port tank and it was full. Rapping the starboard tank produced a distinctive hollow sound as one could imagine. Fortunately for me I was young, stupid, and fearless at that age so I went the the Marina Office and told the manager what happened. She said there were a few 50 gallon blue plastic drums in back of the office and I could use one to recapture the gasoline. So I did. I also warned all the other boater there that day on my dock not to let anyone near my boat as I cleaned the mess up. I was the last boat on that particular dock. That didn't go to plan.
I put the drum on the dock and using a large plastic cup I scooped the gas out of the bilge and poured it into the drum about 16 ounces at a time. The lowest point in the bilge on that style of boat is right below the V-berth. As I was scooping out the last few quarts of gas in the bow of the boat I walked out of the companionway onto the cockpit and saw one of the worst sights I could imagine that day.
There I was covered in gas, and I mean literally, the boat was nothing but gas fumes, there was a rainbow slick on the water surrounding my boat from small spillages during the recovery process, a plastic drum with close to 50 gallons of gas in it on the dock and what do I see? I see a Hispanic fellow with one foot on the dock and his other foot on my gunnel with his arm resting on his knee. In his hand was lit cigarette.
I look at him in astonishment and say, "Hey buddy, this is gas!" pointing to everything around him. He says, "Oh, gasoline, like boom?" I said, "Yea, get that cigarette out of here!" He turns around and starts to flick the cigarette into the water and I tell him don't do that, just walk away fast and take your lit cigarette with you.
Now here is the point I want to make... Boats do indeed have fires and explosions due to gas being the fuel. In fact, a friend of mine spent some time in the burn ward because he reached down and tried to start his engine with a screwdriver by shorting a broken solenoid at the starter. He hadn't cleared the bilge of fumes and was holding the engine hatch open in his bathing suit. The flash severely burned one side of his body and the arm that was holding up the hatch. The boat was unharmed. Him, not so much.
Back on point... gasoline needs a certain combination of elements for it to become unduly dangerous. Air/fuel ratio is certainly at the top of the list and so are ignition sources. The long story I related above was for the purpose of helping people understand the true nature of gasoline as a marine fuel source. I'd be willing to bet that very few boaters have had such an experience as I described above, fully covered in gas with gasoline fumes so heavy it was hard to breath. Yet in spite of those terrible odds nothing bad happened to me that day. Was I lucky? You bet. I'll be the first to admit I dodged a few bullets that day.
But everyday millions of people put gas in their cars and truck without so much as a second thought. It turns out gasoline is not the demon it is made out to be. Can a boater safely use gasoline as a fuel? Well, millions of boaters do it all the time and in fact it is the rarest of occasions when something goes horribly wrong. That was my first boat. My next three boats were gas and the boat my wife and I are looking to purchase this spring will in all likelihood be a gas boat.
Your mileage may vary. No pun intended.
