Gas vs Diesel

[Art]

I know and have experienced all the pros and cons of gas vs. diesel. The one thing that will always push me toward diesel, in a boat where it would be appropriate, is the obvious volatility and explosive difference between the two fuels. I am willing to pay the extra cost in purchase and have the extra weight for that piece of mind. I know that if one is careful and maintains all well gas can be safe but not as safe as diesel. I consider enclosed boats with gas inboards potential bombs and I don't like sitting on bombs. Just my opinion and I am sure plenty will disagree.

I don't disagree. However, I am very comfortable with gas or diesel or even propane... because I'm a stickler on safe operations.

I would like to learn: What is the annual explosion rate for gasoline fueled enclosed inboard engine boats? There must be stats on that number.

 

[psneeld]

Gas isn't 2X as expensive as diesel...used to be.

Gas isn't 2X as dangerous as diesel....used to be.

 

[diver dave]

Turbos on diesels have certainly narrowed the gas/diesel fire gap. But, gas will always win on the explosion ratio.
Used to be that shore power inlets and galley fires led the diesel boat fire causes. Not sure that is true anymore.

 

[psneeld]

Compare car accident fatalities versus boat explosions to put it into perspective....raw stats are pretty useless.

 

[Art]

Over the years/decades:

I've seen burned boats up close, after the fire. Ones I've seen were caused from electrical, BBQ, propane, cigarettes... etc. Most boats I've seen, were before the fire, not looking like they had had the best maintenance/care.

I've read about gas powered boats that burned due to gasoline spills during fillups and small container spills [5 gal plastic and such], gas filter spills and other things.

I've read other times where propane leaks have caused explosion aboard.

I do not recall reading where a boat simply exploded due to it having enclosed gas engines and gas tanks where the vapor reached density of ignition from some heat source.

I do recall reading where boats burned from unexpected gas line leaks that happened in the engine compartment...

That said; Instances mentioned above due to gasoline were not [blow the roof off] explosions, so to say, but rather they were mostly fires that could be dealt with if quick enough actions were taken.

One searing memory [pun intended] I have as a youngster in NY... We were cruising down a canal of fishing boats. One boat had huge billows of smoke and flames in its mid section. There was god awful mechanical screaming noise emanating from the boat. Crew members were frantic. We read days later that the boat had been saved. Reason for fire - runaway diesel engine that even after fuel was shut off it kept feeding on its oil supply, using that as fuel. Article said the way they finally stopped the engine was to cut off air supply.

Physics, baby! It all comes down to physics!

Happy No-Explosion/Fire Daze - Art

 

[BandB]

What we know:

-Boats of all types, with all fuel, with all means of propulsion are subject to potential fires. Most fires are electrical in nature. Galley fires are probably second in leading causes. Not much different than in homes.

-Gas and Propane are more likely to lead to explosions than diesel. However, explosions are rare. Batteries can also explode and do occasionally.

-There are likely more fires on boats with gas. However, there are many times more gas boats than diesel.

-On any type boat there are steps that should be taken to reduce risk of fire.

What I personally conclude:

There is some greater risk in owning a gas boat vs. diesel. However, for nearly my first 42 years of life I was only on gas boats and I never felt unsafe as a result. There were boat fires on the lake, but they were rare and generally had nothing to do with the boat having gas engines. Today, everything else being equal, I prefer diesel. However, everything else is seldom equal. If I found my ideal boat in a price range I could afford and it was gas, then I'd buy it. I'd get the electrical system on any boat I purchased thoroughly checked.

I said above everything else is seldom equal. In certain sizes and types you've find more gas boats available than diesel and in others more diesel. Gas will almost always be less expensive to buy. Then there's weight. That's why diesel outboards haven't become prevalent. We have jet ribs, mostly gas, that we carry on our diesel boats. A Williams 445 (14') with a gas engine weighs 957 lbs and with diesel weighs 1,661 lbs. The gas boat with 100 hp will run 48 mph. The diesel with 110 hp has a top speed of 40 mph.

I see diesel boat owners who preach the horrors of gas boats and yet are carrying a gas dinghy and several tanks of propane they use both inside the galley and outside on the deck. They also drove to their boat in a gas fueled car. Then their response when that is pointed out is to say how they do so safely, the steps they have taken. Ah, they hit the key. Safe use of the fuels we choose. They are carrying the same type fuels they warn are dangerous. Irony can be harsh.

So, if you don't want a gas boat, that's fine and it's even fine to say they scare you, but we must not fearmonger. A gas boat is the right choice for many.

Ford just recalled 230,000 vehicles over the potential of engine fires. Remember years ago the problem they had with fuel tanks in collisions. Then GM with pickups. But let's not be like NBC was in 1992. To dramatize the GM problem with pickups they staged a crash. However, to get the effect they wanted, they used remote controlled incendiary devices.

 

[Nomad Willy]

Art,
Propane is an option of course. So is natural gas.

I drove a propane Buick for several years. Ran perfectly when cold. One can extend oil changes. Ran perfectly when hot. Burns a bit more fuel than a gasoline engine but less than emission controled gas engines. Some women may complain about the fish smell. Sometimes I could notice it by concentrating very hard. Price fluctuates more than gas and of course availibility isn't 100%. I've driven many propane trucks and really like the way they run. A completely different ignition advance curve is required .. much more advance at low speeds and a little less at high speeds. Having a large pressurized propane tank on a boat is something I've never considered. Have you?

 

[Art]

Then GM with pickups. But let's not be like NBC was in 1992. To dramatize the GM problem with pickups they staged a crash. However, to get the effect they wanted, they used remote controlled incendiary devices.

Ahhhh - The origination of blatant "Fake News"!!

"Fake Advertising" way outdates Fake News... "Truth in Advertising" seldom exists in 2017, nor has it for many decades.

 

[Art]

Art,
Propane is an option of course. So is natural gas.

I drove a propane Buick for several years. Ran perfectly when cold. One can extend oil changes. Ran perfectly when hot. Burns a bit more fuel than a gasoline engine but less than emission controled gas engines. Some women may complain about the fish smell. Sometimes I could notice it by concentrating very hard. Price fluctuates more than gas and of course availibility isn't 100%. I've driven many propane trucks and really like the way they run. A completely different ignition advance curve is required .. much more advance at low speeds and a little less at high speeds. Having a large pressurized propane tank on a boat is something I've never considered. Have you?

Nope, and don't intend to.

Only happenstance I ever had with propane powered vehicle was 2004 in a taxi going to SFO for business flight to Atlanta. Half way there the cab suddenly became filled with garlic smell of propane. I told the young driver to pull off because this could explode. He did and called another cab for me. I made the flight. His cab got towed. We're both still alive... well, I guess he is too!

 

[diver dave]

I"m still thinking about gas outboards on a "trawler". Can't quite get this vision out of my head on doing the 100 hour oil change on an outboard at sea.

 

[Art]

I"m still thinking about gas outboards on a "trawler". Can't quite get this vision out of my head on doing the 100 hour oil change on an outboard at sea.

I can believe if everything is set up correctly that o/b's on a relatively small trawler would workout fine. Operative term... "set up correctly"!

 

[nodestination]

A good rule of thumb is that it takes 200 or more hours a year to justify the cost of diesel vs gas based on fuel savings. And I agree with what was said about safety: gassers can be as safe as diesels if proper operation and maintenance is followed.

David

From my own personal experience - gas is never safe. Time ticking bomb. I will never own a gas boat nor I will "park" close to one.

 

[psneeld]

Guess the millions of boats operated by marginally knowledgeable boaters that haven't blown up proves you incorrect that they are all ticking time bombs.

 

[Art]

From my own personal experience - gas is never safe. Time ticking bomb. I will never own a gas boat nor I will "park" close to one.

You have any propane aboard?

 

[SaltyDawg86]

From my own personal experience - gas is never safe. Time ticking bomb. I will never own a gas boat nor I will "park" close to one.

Hahaha wow. Do you wear a tin hat? What do you drive?

 

[Nomad Willy]

I"m still thinking about gas outboards on a "trawler". Can't quite get this vision out of my head on doing the 100 hour oil change on an outboard at sea.

There's really no such thing as an OB trawler but if you have something similar a planing hull would be better because the prop would be deeper and less likely to come out of the water on big waves. A FD hulled boat w an OB on the transom would very likely have significant problems w prop out of the water events. Also the typical OB has the prop considerably further aft and that also will promote prop out of the water events. A good seaworthy boat will have it's prop deep and a bit fwd.

The transon on FD boats is considerably higher because there is rocker in the hull. The "rocker" refers to a convex shape to the bottom. The more rocker the higher the transom will be. Most older sailboats (FD) will have the entire transom out of the water at rest.

For operating on sizeable lumpy waves to really big ones keeping the prop in the water is a good thing. OB's are a bad idea for trawlers IMO.

 

[BandB]

Guess the millions of boats operated by marginally knowledgeable boaters that haven't blown up proves you incorrect that they are all ticking time bombs.

He didn't say how long they had to tick.

 

[FlyWright]

Hahaha wow. Do you wear a tin hat? What do you drive?

If you knew what ND has gone through, you probably wouldn't say that. He's lived through a great loss as a result of a gasoline explosion. Burn me once, shame on you, burn me twice...

 

[psneeld]

He didn't say how long they had to tick.

Oh, I forgot.

They all eventually blow up, my bad.

 

[SaltyDawg86]

If you knew what ND has gone through, you probably wouldn't say that. He's lived through a great loss as a result of a gasoline explosion. Burn me once, shame on you, burn me twice...

I'm not doubting that, but wow...what a comment. What events lead to that? It's not like one day it decided to blow up. Otherwise we would see cars/boats/planes/etc blowing up all the time.

 

[nodestination]

3 experienced boater - not "Sunday drivers" were transferring fuel from leaking tank to external. They tough that they took all the safety checks. 2 of they recover from burns, but the 3rd one ( owner) still in recovery. I felt the explosion and few minutes latter, I watch my boat burns. To all those jokers - I hope that this will never happen to you. Cars have open engine compartment, but boats have close one. All the fumes are accumulating and even the smallest spark will set it up. Brushless electric motors are safe when they are new, but with time, the bearings wear up and will create the spark(blowers). Fumes are setting in bilge area and faulty bilge pump or wiring will blow the boat. Diesels do not explode. The problem I see - if someone blow their boat up, it does not only affect them, but every one around too. You may get lucky and still have boat, but it is only a matter of time. You want to take a chance - good, just stay the hell away from me.

 

[Donsan]

Oh, I forgot.

They all eventually blow up, my bad.

One blew up next to his boat and took his previous trawler with it but if I recall, it was a piece of junk gasser and the owner was working on it.

 

[sdowney717]

Old blower motors spark?
They have bronze sleeve bushings.
Mine is from 1970, and works and you know what, if the bronze bushings were worn that far, the armature will drag on the stator and it won't run or hardly at all. It won't run because it becomes magnetically unbalanced, one side will pull harder than the other. Or it will squeal real loud and not blow the proper amount of air, but the motor wont be leaking out sparks.

 

[diver dave]

There's really no such thing as an OB trawler but if you have something similar a planing hull would be better because the prop would be deeper and less likely to come out of the water on big waves. A FD hulled boat w an OB on the transom would very likely have significant problems w prop out of the water events. Also the typical OB has the prop considerably further aft and that also will promote prop out of the water events. A good seaworthy boat will have it's prop deep and a bit fwd.

The transon on FD boats is considerably higher because there is rocker in the hull. The "rocker" refers to a convex shape to the bottom. The more rocker the higher the transom will be. Most older sailboats (FD) will have the entire transom out of the water at rest.

For operating on sizeable lumpy waves to really big ones keeping the prop in the water is a good thing. OB's are a bad idea for trawlers IMO.

I can't dissagree with these points.

here is the trawler that prompted my post:

TT35 Specifications - Great Harbour Trawlers

I can envision over revs at the worst times.

 

[psneeld]

Yep out of millions of gassers, the one that blows up proves all are ticking time bombs.

Thats why we all do everything tbe same as each other in life so we all live tbe exact same number of years.

Same cars, same mechanics, same miles covered, go out in the same weather, etc...etc...

Sometimes one comnent in TF creates a whole new topic....while some people have crusades, fortunately the world still turns when reason reenters the discussion....not that the input isnt important, it just doesnt have to become a rule.

 

[nodestination]

One blew up next to his boat and took his previous trawler with it but if I recall, it was a piece of junk gasser and the owner was working on it.

Yes, it was piece of junk twin engine gasser. They use it extensively for salvage operation (lifting sunken boats, towing). I watch then taking that boat out many times and I saw all the "safety check" before start. During the fuel transfer, the battery's were disconnected and the fuel pump was manual ( approved for gas fuel transfer). To this day, they still do not know what was the cause of explosion. Maybe the boat decided to commit a suicide?.

 

[smitty477]

3 experienced boater - not "Sunday drivers" were transferring fuel from leaking tank to external. They tough that they took all the safety checks. 2 of they recover from burns, but the 3rd one ( owner) still in recovery. I felt the explosion and few minutes latter, I watch my boat burns. To all those jokers - I hope that this will never happen to you. Cars have open engine compartment, but boats have close one. All the fumes are accumulating and even the smallest spark will set it up. Brushless electric motors are safe when they are new, but with time, the bearings wear up and will create the spark(blowers). Fumes are setting in bilge area and faulty bilge pump or wiring will blow the boat. Diesels do not explode. The problem I see - if someone blow their boat up, it does not only affect them, but every one around too. You may get lucky and still have boat, but it is only a matter of time. You want to take a chance - good, just stay the hell away from me.

This is a terrible story and I am very sorry to hear anyone was so severely injured by these events.
Once you have any type of leaks there are not so many 'experienced' individuals that would be ready to handle it. Those that would know how to handle it could have been called in as a best approach - then the 'experts' would have handled the leaking fuel in the bilges.
It has been many years since I attended the JT Baker fire preventions school for commercial applications with flammables and explosives but the ones that are trained would have handled this atypical leak with safety.
One aspect of an experienced boater is when he calls in for help - with a mechanical issue, with outfitting a boat, with safety gear or with anything he knows is outside his/her area of expertise.

I am very glad no-one was killed and hope for a full recovery for all involved.

 

[Codger2]

The one thing that will always push me toward diesel, in a boat where it would be appropriate, is the obvious volatility and explosive difference between the two fuels. .

That's really the crux of the matter, isn't it. I have read every post in this thread and it hasn't changed my mind one bit! A gas boat is not as popular as a diesel because of the safety factor.

 

[psneeld]

Just remember, atomized diesel is also flammable, explosive.

I have had one of these in my 55 years of boating, but never a threatening gas issue.

Go figure....stats or the occasional personal experience is usually never a final answer in a case by case situation.

 

[dhays]

This thread has drifted quite a bit. One issue I have on my boat that was called out by the surveyor as a "recommendation" is that the sight tubes have a valve at the bottom of the sight tube but not one any the top.

In the case of an ER fire, the sight tubes will melt. If the valve at the bottom is not closed, the diesel will then empty into the ER fueling the fire. The top of the sight tube doesn't go all the way to the top of the tank. So with a full tank about 75 gallons of diesel could flow out of the sight tube into the ER. I intend to put a valve at the top of that sight tube eventually.