Gas vs Diesel

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I have personally put out a major fire in a diesel engine room. Caused by an oil leak and a hot dry turbo. Also have participated in the investigation of a few diesel/turbo/fuel or oil based engine room fires.

Also have been in an engine room where an engine at full power ingested oil, ran away, blew the turbo and but for pure luck did not catch the engine room on fire. Oil sprayed on lagging and caught fire, but fire did not spread. Smoke in engine room and salon prevented us from fighting fire. Told cap'n to put it on the beach, but fire reduced before we got there, smoke reduced and I was able to get in there with a fire X. Engine was blown.

And then we just had that classic Rybovich SF burn up and sink off Marathon.

So yes, diesels are not immune to fire risk. Maybe more fire risk than gassers due to turbos, especially dry turbos. Fortunately not so many dry turbos now, but there still are some being produced and some still in the fleet.

Diesel sprayed on hot metal will actually ignite at a lower temp than gasoline. And lube oil even lower temp than diesel.

The two things diesel won't do is vapor explosions and have high CO poisoning risk.
 
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. :facepalm:

Yes Dave,
The long straight bottom will act as a "teeter totter" and lever the stern out of the water .. and then the prop is aft of the stern. Not a trawler. Many use the term "trawler" for marketing reasons. At speed on flat water the tt should be a nice running boat.
 
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.

Had I witnessed and been directly impacted, I probably would feel the same way. However, this was not ordinary operation of boats. It was by it's very nature a very dangerous activity that shouldn't have been done on a dock next to other boats and should have had more precautions taken. Still, you were around an explosion and fire and I know you'll be forever impacted by it.

I had a friend lose their home to an explosion and fire which originated at a neighbor's house. The house was recently purchased and undergoing renovations. One handyman removed a heater and shut the gas off before doing so. The house wasn't lived in at that time. People moved in and another handyman did some repairs and checked the hot water heater, found the gas not turned on and turned it back on. He knew nothing about the first man removing the heater, but the gas where the heater had been was never capped. The explosion came later. A four month old died.

The debris hit all over the neighborhood, but a lot of the roof landed on my friend's home next door and it caught fire. They weren't home and arrived back as their house was burning and the firemen were only trying to contain the fire and protect other homes.

They were scared of any house with natural gas, which was virtually every home in the area, any neighborhood with it. Temporarily they rented a house we had lived in out in the country, all electric. Then finally they bought land and built in the country.

Even if what we witness is a rare event and regardless of the cause, we never get beyond the trauma.

We each fight that. Whether it's a house, a boat, a car, or a plane. I recall after 9/11 the fears of people who worked in tall buildings downtown, although there was no reason to believe Charlotte would be a target. When I next flew and the plane took off, it shocked me when the thoughts of the planes on 9/11 crossed my mind and I had a feeling of uneasiness I'd never had before. I had no idea that at the same time my wife was at work worrying about me flying that day.

I totally understand nodestination's feelings. Still it doesn't scare me away from gas. It does remind me to we wary of potential dangers and also to object to activities taking place on the docks that shouldn't and are often forbidden.
 
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.

Interesting but the practicality eludes me, considering the fire melting the plastic sight tubes and who then is going to reach in to turn off manual valves surrounded by flaming hot fire?
And who is going to remember to do such a thing in the middle of experiencing an engine room fire.
 
Are there any reports of boats blowing up while underway? Seems like you only hear about them blowning up while at the dock.

My plan is to run the bkowers all the time while underway. Also I'm going to open the engine hatch and take a sniff before powering the boat up after it's been sitting. I feel like that should reduce the chances of an explosion as much as possible.

Airliners have center fuel tank restrictions when it comes to fuel levels. Also pilots aren't allowed to reset any tripped breakers that have anything to do with fuel. This is all from TWA 800 that had a faulty center tank fuel pump. The conditions were just right that caused the explosion.
 
Are there any reports of boats blowing up while underway? Seems like you only hear about them blowning up while at the dock.

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Yes, there are. UN1K off Malaysia. Pegasus in Galway Bay. Limitless in the BVI. A Kuwaiti boat near Khairan, but that one was part of a collision. A yacht near Penang last year. Gili Cat 2 near Bali. 15 mtr yacht near Rorotonga.
 
Interesting but the practicality eludes me, considering the fire melting the plastic sight tubes and who then is going to reach in to turn off manual valves surrounded by flaming hot fire?
And who is going to remember to do such a thing in the middle of experiencing an engine room fire.

I don't have 'em, but I believe the standard practice in boats with sight tubes and valves is to open the valve to observe the fuel level, then close the valve when you're done. This way, the valves are normally in the closed position except while observing fuel levels.
 
I don't have 'em, but I believe the standard practice in boats with sight tubes and valves is to open the valve to observe the fuel level, then close the valve when you're done. This way, the valves are normally in the closed position except while observing fuel levels.

:thumb: Yep, that's the proper way to use 'em.
 
ND - "I saw all the safety checks" - I suspect the receiving drum, tank, whatever and associated system was not electrically bonded. Real important, in my experience, particularly when defueling.

As to vapor accumulating in the bilge - that's just pure and simple crappy maintenance or a failure to respond to an equipment casualty. And, they make sensors for that.

If gassers are a ticking time bomb, there are tons of Atomic 4s out there just waiting to go off.
 
Well.... I will be banished, but I made the jump. I now own a boat, but it's in no way a trawler or even a cruiser lol. It's a 2000 Glastron SX 195 bow rider. Something to use for the next couple of summers while my 2 year old gets a little older and we can stash some cash for a 40 ft trawler. Maybe I'll make it my tender once I get a trawler haha
 
Well.... I will be banished, but I made the jump. I now own a boat, but it's in no way a trawler or even a cruiser lol. It's a 2000 Glastron SX 195 bow rider. Something to use for the next couple of summers while my 2 year old gets a little older and we can stash some cash for a 40 ft trawler. Maybe I'll make it my tender once I get a trawler haha

Congratulations. One can have a lot of fun with a Glastron Bow Rider. Where are you keeping the boat? You appear to be near Pagan River and nice access to James River so nice calm areas for boating on those days the Chesapeake isn't as calm.
 
Well.... I will be banished, but I made the jump. I now own a boat, but it's in no way a trawler or even a cruiser lol. It's a 2000 Glastron SX 195 bow rider. Something to use for the next couple of summers while my 2 year old gets a little older and we can stash some cash for a 40 ft trawler. Maybe I'll make it my tender once I get a trawler haha

Congratulations! Just upped my oil company stock holdings! :angel:
 
Well.... I will be banished, but I made the jump. I now own a boat, but it's in no way a trawler or even a cruiser lol. It's a 2000 Glastron SX 195 bow rider. Something to use for the next couple of summers while my 2 year old gets a little older and we can stash some cash for a 40 ft trawler. Maybe I'll make it my tender once I get a trawler haha

Is it an o/d or o/b? Glastron made [I guess still makes] some really fun and well built runabouts. Yes... if that boat pans out correctly, do keep it for your tow behind. It will serve you well in many ways! :thumb:
 
Is it an o/d or o/b? Glastron made [I guess still makes] some really fun and well built runabouts. Yes... if that boat pans out correctly, do keep it for your tow behind. It will serve you well in many ways! :thumb:

They were a hot boat when I was growing up. Still I think a nice way to get started. Beneteau has cut their line and Four Winns line back some since they bought them.
 
I'll be keeping it at my house. My wife is going to sew new seat covers and we're looking forward to having some fun on the James and Pagan Rivers. Not looking forward to the small engine bay though!
 
I'll be keeping it at my house. My wife is going to sew new seat covers and we're looking forward to having some fun on the James and Pagan Rivers. Not looking forward to the small engine bay though!

Photos - Please!!
 
Are there any reports of boats blowing up while underway? Seems like you only hear about them blowing up while at the dock....
I acted for a couple severely injured in a gas boat under way explosion. In fairness it had just been refueled and had just started a second engine, I think you are right, often it relates to refueling mistakes.
The consequences of the case were horrific, incl the death of a baby.
Perhaps fuel injection reduced the incidence of fuel leaks(not that it did much for older EFI Jaguars, fortunately the cross flow heads saved the fuel dripping onto the exhaust manifold).
Spare gas for my dinghy outboard gets lashed on deck, the outboard is not stored in the bilge, or the lazarette.
I usually drive to the boat in a diesel car, but it was only engine available, not because I`m afraid of gas cars blowing up. Though I did once set fire to a Mazda rotary while clearing a flooded engine.
 
Gallon for gallon, diesel fuel contains more energy than gasoline. For some reason though, gasoline costs more than diesel fuel, sometimes a lot more. And you don't have to deal with ethanol adulterated gasoline. You will go further on a gallon of diesel than gasoline.


Diesel fuel doesn't go stale. Gasoline does, especially when it has been adulterated with ethanol.


Diesel engines typically go for 10,000 hours or more without needing a rebuild. A gasoline engine's life is about a tenth of that.


Diesel engines don't need "tuneups". No spark plugs, etc. Change the oil and filters and you're good to go.


Diesel powered boats cost more than an equivalent gasoline powered boat but you will typically get most of that back when you eventually sell the boat.


Diesel powered boats are safer than gasoline powered boats. You don't need ignition protected parts or power tools when working around the engine or fuel system.


It's your choice of course, just do your research before spending your money.
 
Gallon for gallon, diesel fuel contains more energy than gasoline. For some reason though, gasoline costs more than diesel fuel, sometimes a lot more. And you don't have to deal with ethanol adulterated gasoline. You will go further on a gallon of diesel than gasoline.


Diesel fuel doesn't go stale. Gasoline does, especially when it has been adulterated with ethanol.


Diesel engines typically go for 10,000 hours or more without needing a rebuild. A gasoline engine's life is about a tenth of that.


Diesel engines don't need "tuneups". No spark plugs, etc. Change the oil and filters and you're good to go.


Diesel powered boats cost more than an equivalent gasoline powered boat but you will typically get most of that back when you eventually sell the boat.


Diesel powered boats are safer than gasoline powered boats. You don't need ignition protected parts or power tools when working around the engine or fuel system.


It's your choice of course, just do your research before spending your money.

Agree but for me the main factor is volatility. Sure diesel will burn so will FG and aluminum but under what conditions? To make diesel explode we put it under very high compression like in our engines. Leaking diesel in the ER a relatively common event rarely causes a fire and if gas was leaking that often boats would be going off like fire-crackers. A much greater standard of care is needed for safe gas use relative to diesel in enclosed spaces. To make gas explode one cup full in the bilge a spark and you need a emergency room and a good insurance company. I am not saying gas cannot be safe it just takes much more to make and keep it safe.
 
A lot of 100 to 1 or million to one assumptions.

A cup of gas in tbe bilge doesnt mean an explosion with a gas boat . I have been in that situation dozens of times and been around hundreds of boats with the same issue that didnt blow up.

Can one make boating entirely safe? Well, stay tied to the dock and never turn anything on and you have a better chance.

The other alternative is to know, maintain and operate your boat in a safe manner.

Some gas engines these days are lasting as long as some diesels...depends on what you have...and how you maintain and operate it.

Sure there are combos of boats and engines that make more sense, but some of that is how the boat was used and how you plan on using it.

Research is good, and more and more gas is coming back into favor except for certain use or large vessels.
 
Agree but for me the main factor is volatility. Sure diesel will burn so will FG and aluminum but under what conditions? To make diesel explode we put it under very high compression like in our engines. Leaking diesel in the ER a relatively common event rarely causes a fire and if gas was leaking that often boats would be going off like fire-crackers. A much greater standard of care is needed for safe gas use relative to diesel in enclosed spaces. To make gas explode one cup full in the bilge a spark and you need a emergency room and a good insurance company. I am not saying gas cannot be safe it just takes much more to make and keep it safe.

Unbelievably, auto ignition point of diesel where it auto combusts is lower than gasoline.

Fuel Flash point Autoignition

Ethanol (70%) 16.6 °C (61.9 °F)[5] 363 °C (685 °F)[5]
Gasoline (petrol) −43 °C (−45 °F)[6] 280 °C (536 °F)

Diesel (2-D) >52 °C (126 °F)[6] 256 °C (493 °F)

Jet fuel (A/A-1) >38 °C (100 °F) 210 °C (410 °F)
Kerosene >38–72 °C (100–162 °F) 220 °C (428 °F)
Vegetable oil (canola) 327 °C (621 °F) 424 °C (795 °F)[8]
Biodiesel >130 °C (266 °F)
 
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Anyone feel like compiling the data for.those.hurt in gasoline related mishaps.compared to all other boating mishaps?

Bet it would suprise many.....

Especially if one dug a little deeper and found the actual causal.factors of gasoline mishaps.
 
A lot of 100 to 1 or million to one assumptions.

A cup of gas in tbe bilge doesnt mean an explosion with a gas boat . I have been in that situation dozens of times and been around hundreds of boats with the same issue that didnt blow up.

Can one make boating entirely safe? Well, stay tied to the dock and never turn anything on and you have a better chance.

The other alternative is to know, maintain and operate your boat in a safe manner.

Some gas engines these days are lasting as long as some diesels...depends on what you have...and how you maintain and operate it.

Sure there are combos of boats and engines that make more sense, but some of that is how the boat was used and how you plan on using it.

Research is good, and more and more gas is coming back into favor except for certain use or large vessels.

Paul speaks truth... from having his hands-on the marine-pulse for decades, including today. He is aboat [pun intended] as close to the real marine-deal as anyone I've known.

Paul not only sees marine doings from a helicopter view; he also sees it close up and personal.
 
My dim recollection of expert reports years ago is that for gas to cause an explosion a concentration of 5% gas 95% air is required. Those proportions can change repeatedly as air enters the bilge, a mixture can change from non explosive to explosive and vv, ie(in Goldilocks` language) too rich/too lean/just right. Is that right?
 
She needs a little sprucing up, but there she is. We'll have some fun this summer but my goal is to have a bigger boat before the end of 2018.

My 2 year old loves it. I can't peal him out of it haha


ForumRunner_20170629_235012.jpg
 
Gas and diesel can be and are safe. So here is a situation to ponder. You are running at cruise speed and have a fuel leak in the bilge unknown to you. Would you rather be on a gas powered boat or diesel? pick one no other choices allowed.
 
I have been on gas boats snd diesel boats, both with fuel leaks.

You can smell fuel long before it is dangerous...usually.

Probably why most explosions are during or right after refueling because people associate the smell to the refueling and not a different problem.

It may depend on the boat, but I dont worry about either. If I was regularly running a gas boat with a well sealed bilge from the cabin, I would make darnn sure the sniffers worked and fuel system was checked regularly......no different than the propane system on my diesel boat.
 
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Gas and diesel can be and are safe. So here is a situation to ponder. You are running at cruise speed and have a fuel leak in the bilge unknown to you. Would you rather be on a gas powered boat or diesel? pick one no other choices allowed.

That happened to a friend of mine the other day. A leak in an injector pipe. This sort of leak sprays furl it doesn't drip.

Luckily, he has a diesel boat.
 
That happened to a friend of mine the other day. A leak in an injector pipe. This sort of leak sprays furl it doesn't drip.

Luckily, he has a diesel boat.

That's not too lucky either way. Diesel fuel misting like that makes it much more flammable than just a puddle of diesel. Glad to hear it ended well.

I don't know specific numbers, but a lot of work boat fires in the ER are due to little leaks that mist fuel vs big streams of fuel.
 
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