Safety of Gas Engines

[Tony B]

I am still looking at trawlers and motoryachts.

All*of the trawlers that I have looked at in my price range so far have diesel engines but the rest of the boat is pretty well shot.

The other alternative is a motoryacht. Most motoryachts have gas engines. I feel safe on them when I know they*have been well maintained.

Most people I know say "NO"

What say you?*

 

[Carey]

Gas engines are as safe as the owner and operator allow. Well maintained, and ventilated, they can be fine.

 

[Larry M]

Lena and I owned a 1966 Chis Craft when we lived in the PNW.* We took that boat from Olympia to Vancouver/Vancouver Island*and cruised year round.* It had a 350 cubic inch gas engine.* We never*felt there were any safety issues.* It was a great boat and as far as*we know it is still out there.* Both Willy and Carey are spot on.

 

[psneeld]

Gas is a safer than what it is made out to be..but as been posted...maitenance and operator are the real keys.

I always said that if I couldn't find the right trawler but did find the right style aft cabin motoryacht...I buy her..run the gassers a few years while I tried to pick up a pair of 75-100hp diesels used, out of commercial trailerable gennies/light towers, etc..etc..

 

[Moonstruck]

I had two friends that their lives were cut short by a gasoline generator on a well maintained 36' Pacemaker. They were smart meticulous people. *He a CFO for a large national fast food chain. *She a director of adult literacy programs. They were extremely careful----even anal. *CO is colorless, odorless, and tasteless. *It is a killer. *CO killed another friend in her home.

I have not seen a diesel boat explode, but have seen gas boats explode

Diesel if you can. *Careful if it's gas.


*


-- Edited by Moonstruck on Tuesday 21st of February 2012 07:02:42 PM

 

[rwidman]

I have a friend who is an experienced boater, boat owner, and a part time boat mechanic. He just bought a motoryacht with two gasoline engines and a gasoline genset.

I went with him to bring it home, a two day trip. First thing, he fires up the blower, then imediately fires up the engines. We stopped for fuel along the way and same thing after taking on gasoline, he fires up the blower and imediately fires up the engines. What can I say, he is supposed to be the expert.

The CO detectors are original to the boat, eleven years old.* Service life on those detectors is about three years.* I pointed this out to him, we'll see if he replaces them.

Having a diesel engine provides a lot of peace of mind both for the fire/explosion danger, and for CO.* I added a CO detector to my boat in case CO from another boat gets in.

 

[markpierce]

Most of us feel safer with a diesel-powered boat.* (And I like the heavy growl of a diesel engine's exhaust.)


-- Edited by markpierce on Tuesday 21st of February 2012 08:17:35 PM

 

[psneeld]

rwidman wrote:
I have a friend who is an experienced boater, boat owner, and a part time boat mechanic. He just bought a motoryacht with two gasoline engines and a gasoline genset.

I went with him to bring it home, a two day trip. First thing, he fires up the blower, then imediately fires up the engines. We stopped for fuel along the way and same thing after taking on gasoline, he fires up the blower and imediately fires up the engines. What can I say, he is supposed to be the expert.

The CO detectors are original to the boat, eleven years old.* Service life on those detectors is about three years.* I pointed this out to him, we'll see if he replaces them.

Having a diesel engine provides a lot of peace of mind both for the fire/explosion danger, and for CO.* I added a CO detector to my boat in case CO from another boat gets in.

*Bad decision making doesn't mean gas engines are dangerous...ANYTHING is dangerous if you ignore basic safety rules.

Sure diesels have advantages...but todays gas engines are safe, reliable and are coming closer to diesels in many respects...unfortunately...price too!

 

[markpierce]

Tony B wrote:
All*of the trawlers that I have looked at in my price range so far have diesel engines but the rest of the boat is pretty well shot.

*Continue your search.

 

[johnma]

Our current boat is a diesel, but the last two were gas. If you pay attention to the safety regulations for gas I feel they are just as safe. that said, the real issue for running gas engines now is ethanol. It works fine in a car engine because you will go through a tank regularly. Not so in a boat. Ethanol looses stability after a few months. It eats fiberglass gas tanks, it eats some hose material, carb floats, etc. I never had a problem with it because I paid a lot of attention to maintenance. But every spring I see a lot of people in marinas in our area have to have their carbs or fuel injection systems rebuilt.
John
390 Mainship

 

[Boathommy]

Never start the boat without putting your nose in the bilge. Pretty damn simple since that is required to check the oil and water . . .
If you have the extra $75-100, buy a diesel, I would. You'll get it back in the sale. If you don't, buy the boat that works for you and PAY ATTENTION.

 

[7tiger7]

I personally think gas engines on boats are only acceptable as outboards. I do think gas inboards can be dangerous - but more importantly, I think gas inboards are a pain to keep running right in a marine environment...

I would not consider buying a trawler type boat with gas engines, but thats my opinion.

 

[Budds Outlet]

I'm running a gas boat now but the pending trawler will be diesel. So will the genny.* I may die at sea but I don't want to die in a boat explosion and I don't want to die from CO poisoning.

*

 

[Tony B]

"If you have the extra $75-100, buy a diesel"

More like $15,000 to $20,000. Look at yachtworld and compare.

 

[Moonstruck]

7tiger7 wrote:
I personally think gas engines on boats are only acceptable as outboards. I do think gas inboards can be dangerous - but more importantly, I think gas inboards are a pain to keep running right in a marine environment...

I would not consider buying a trawler type boat with gas engines, but thats my opinion.

*That is my thinking. *Outboards are fine. *Fittings, hoses, connectors, and fuel tanks are all subject to failure. *Gasoline is heavier than air. *Boats don't have vents in the bottom. *The only way to remove any accumulated gasoline or propane fumes is with mechanical extraction. *I know that cooking with electricity means running the generator. *That is a trade off I am prepared to make for peace of mind.

 

[Art]

Tony
*
I currently have the original twin 1977 gas-powered 350 cid 255 hp carbureted Mercruisers and a 7.5 Kohler gen-set in my 1977 Tollycraft.* I check and service all three engines on a dated log; they always remain in top condition.* Both drive motors have about 300 hrs each since professional rebuilds.* CO alarm we check before each boat usage... Went off once from exhaust station wagon effect when we mistakenly left master stateroom rear door open while piddling down a long canal, we as usual were on the bridge.* I religiously run the blower for a minimum of ten (10) full minutes (sometimes much longer while accomplishing other items) before starting any motor.* At beginning of blower usage I always lean out the up-galley slider door to smell the blower fan exhaust vent on side of hull... so far never smelled gas fumes.* If boat has been sitting for a period I also open the hatches in salon floor and do a see & sniff test, with spotlight if it is dark.
*
On Atlantic and Pacific, thousands of hours combined, Ive cruised several gasser boats in my life and one with Perkins diesel.* Each type of propulsion has its pros and cons... in craft 40 and below.* Over 40 I would go diesel.* As has been said in other posts to this thread safety of a gasoline powered inboard is up to the Captain ONLY!*
*
Regarding gallons per hour: Twin gassers and a planing hull such as our Tolly tri cabin (when operated one screw at a time) can be used quite efficiently in just below hull speeds.* I get 2 + nmpg at 6.5 knots running on one; I alternate engines each hour.* If I power up with both motors and plane at 15 to 16 knots it gets about 1 nmpg.* If weather threatens, or for any other need-be reason, I can run up to 21 + knots at 4300/4400 rpm (4500/4600 is WOT).* Then I feel ½ nmpg would be about the best I could hope for!* OUCH!!* Luckily I nearly never need to go that fast except for a few minutes and have only done so three times in years of use.
*
Happy Boat Search - Art

 

[psneeld]

More old wives tale crap about methanol and worry about fire and explosion...as an assistance tower I see a pretty good cross section of hundreds of boats each teay...many are out of the methanol conversion problems a year or so ago...just how many boat fires/explosions*are because of a NORMALLY maintained and operated gas engine each year?

get a grip folks...you stand a much bigger chance of dying on our hyways that from methanol or gas engines blowing you up.

Notice how I didn't discuss CO...that's a biggie....I would use at least 3 levels of safety alarms and other safety precaustions using a gas genset and sleeping aboard.

 

[FF]

Overall for a non commercial boat (200hours a year not 24/7) the gas will be far and away cheaper to operate overall.

The maint is far less , and less specialized , fluids are cheaper and in smaller quantities. Many parts are 1/10 price for gas.

Quarts of oil rather than Gallons cheaper antifreez ....

The biggest hassle with gas is the short life of the fuel in the tank.

Diesel can be a decade old and with good filtration still power the boat.

Todays piosoned gas with ethanol is a bigger problem.

Good fueling techniques ,along with better filtration., and in some areas the availibility of NON ethanol diluted gas solves the problem,

 

[rwidman]

psneeld wrote:
More old wives tale crap about methanol and worry about fire and explosion...as an assistance tower I see a pretty good cross section of hundreds of boats each teay...many are out of the methanol conversion problems a year or so ago...just how many boat fires/explosions*are because of a NORMALLY maintained and operated gas engine each year?

get a grip folks...you stand a much bigger chance of dying on our hyways that from methanol or gas engines blowing you up.

Notice how I didn't discuss CO...that's a biggie....I would use at least 3 levels of safety alarms and other safety precaustions using a gas genset and sleeping aboard.

"Methanol" ?

*

 

[rwidman]

Gasoline power in a boat is inherently less safe than diesel power.

How do we know that? Because of the extra safety equipment that must be installed in a gasoline powered boat. The short list includes blowers to extract gasoline fumes, ignition protected starters, alternators, voltage regulators, and anything else electrical that is installed in the engine room or compartment such as inverters, battery chargers and heaters, and CO detectors in sleeping quarters.

Now if all that equipment is installed and in good working order, and the safety proceedures are followed as far as closing the boat up while fueling and running the blowers for four minutes before starting the engines, a well maintained gasoline powered boat should be as safe as a diesel powered boat without all this equipment and precautions.

As in my example above, lots of people will overlook some of these precautions because they haven't personally seen a boat explode. Will you really run the blower for four minutes before starting the genset so you can watch The Price Is Right on TV? Somehow, I doubt it.

 

[JohnP]

Old Stone wrote:
I have one of each. the 40' has big block Chryslers - 40 gls/hr.* plan to give it away on top of that.

********* Carl,* Give it to TonyB and be done with it.* Happy Spring!

JohnP

 

[psneeld]

rwidman wrote:psneeld wrote:
More old wives tale crap about methanol and worry about fire and explosion...as an assistance tower I see a pretty good cross section of hundreds of boats each teay...many are out of the methanol conversion problems a year or so ago...just how many boat fires/explosions*are because of a NORMALLY maintained and operated gas engine each year?

get a grip folks...you stand a much bigger chance of dying on our hyways that from methanol or gas engines blowing you up.

Notice how I didn't discuss CO...that's a biggie....I would use at least 3 levels of safety alarms and other safety precaustions using a gas genset and sleeping aboard.

"Methanol" ?

*

*sorry was just reading alternative fuels article and it stuck..


-- Edited by psneeld on Wednesday 22nd of February 2012 07:35:45 AM

 

[psneeld]

rwidman wrote:
Gasoline power in a boat is inherently less safe than diesel power.

How do we know that? Because of the extra safety equipment that must be installed in a gasoline powered boat. The short list includes blowers to extract gasoline fumes, ignition protected starters, alternators, voltage regulators, and anything else electrical that is installed in the engine room or compartment such as inverters, battery chargers and heaters, and CO detectors in sleeping quarters.

Now if all that equipment is installed and in good working order, and the safety proceedures are followed as far as closing the boat up while fueling and running the blowers for four minutes before starting the engines, a well maintained gasoline powered boat should be as safe as a diesel powered boat without all this equipment and precautions.

As in my example above, lots of people will overlook some of these precautions because they haven't personally seen a boat explode. Will you really run the blower for four minutes before starting the genset so you can watch The Price Is Right on TV? Somehow, I doubt it.

*No I never run blowers on a gas boat...that's an insane waste of my valuable time...*

I crack a hatch to the bilge and sniff...in less than 5 seconds I know the right answer.

 

[sunchaser]

My experience with big block gas (383 Chryslers) in a large vessel says keeping to hull speed yields about 1 - 1.3*nmpg at 1700 - 1800*RPM. Modern gassers according to boat reviews posted in the various magazines shows a bit better* for a 20,000**lb Cruisers, Four Winns or*Searay.

As best I recall, the 44 Tollys ( an efficient and*great hull design) with gas get about .5 to .7 nmpg at 18 - 20 knots and .8 to .9*nmpg with 3208 Cats at same speed. These are the last*+40' vessels that offered gas or diesel on the same hull that I am aware of - you can find either today in the PNW*with about a $40 to*$60K price differential. Many gasser Tolly*44s have been converted to diesel. One of the better I have seen used a 330 HP*Cummins. Surprisingly, the Cummins being a 6 afforded a bit better ER layout than a V8 diesel or gas.

Buying a Tolly 44 gasser and planning for a diesel drop in at a later date may not be a bad idea, if you don't mind turning wrenches and being a carpenter. A gentleman on boat diesel reported at length on a 44 Trojan conversion, another good gas to diesel choice.

 

[Art]

Tony
*
Important items regarding gas motors that*I neglected to mention on my other post, and, as may have been alluded to on other posts herein:
*
-********NEVER, NEVER, NEVER sleep inside boat with gasoline gen set or engines running when boat is not moving, no matter what alarms are on board or how secure you feel with the fuel system being tight (i.e. leak/fume free) or how much ventilation from outside you feel is occurring.* Also, with any gas motor running, always keep one or more CO alarms operational and keep some exterior airflow areas open into interior sections of boat when persons are inside or soon to go inside... being that you are anchored, docked or cruising at any speed.
*
-********Properly maintained (good lubricants with often-change intervals are the name of the game) and run correctly gasoline engines useful duration hours (before rebuild or replacement) will approach that of diesel.* Ive seen and had gas engines still running strong at 3000 hours.* Rule of thumb for gas engines: Averaged rpm at cruise should be no more than 60% of WOT; with gas engines, less averaged rpm generally = increased life span.* Gas engine power ratio to cubic inch displacement: Again less is more regarding increased lifespan, i.e. good ratio is approximately .7 hp to 1 cid.* Soon as gas engine gets into 1 to 1 hp to cid ratio engine lifespan will generally decrease.* Above 1 to 1 ratio, where hp is greater than cid, and a considerably lower lifespan usually occurs on gas engines.
*
-********Properly shopped and self installed portions/items/parts on gas motors can be extremely affordable and easy to accomplish*compared to diesel motors.* Gas engines rebuild or replacement is also relatively low cost.* 1/5^th to 1/10^th cost comparison to diesel*is not unusual.* And, gas engines in a well laid out ER (such as I show in picts of previous post) are pretty much a snap for keeping a good maintenance schedule or for changing parts when required.* Also, gas engine mechanics are plentiful and usually reasonably priced... when assistance is needed.
*
Cheers! - Art

*
PS: I use Soltron fuel additive and experience no stale gas problems.* As well, the*aluminum gas tanks*remain clean. Informative site: http://www.soltron-gtr.com/english.htm*


-- Edited by Art on Wednesday 22nd of February 2012 11:25:46 AM

 

[jeffnick]

If you have a diesel, there's no question...diesel is best. There's something macho about a diesel that attracts us, and I don't dispute that as a valid reason to own one.

I've had both. The pervasive diesel smell turns me off, as does the mechanical (and now electrical) complexity. My carbed 350 gives me a sense of comfort and independence. I'll gladly live with the 'inherent dangers' for the peace of mind associated with easy and cheap do it yourself maintenance and parts.

 

[Marin]

Tony B wrote:

The other alternative is a motoryacht. Most motoryachts have gas engines. I feel safe on them when I know they*have been well maintained.

*How are you defining "motoryacht?"* To me, a motoryacht is a tri-cabin cruiser (trawler if you must but I don't use that term for our boats) with a full-width aft cabin.* Another term for it is "sundeck."* But Grand Banks calls them "motoryachts" so that's the image the term conjurs up in my mind when I hear it.

So to me, most motoryachts are diesel powered.

As to gas vs diesel, I think it's more to do with the type of boat than the type of engine.* For many years I fished on a gas powered boat in Hawaii (Uniflite sportfisherman, twin Chrysler V-8s and Vee-drives).* Never had any problems or concerns.

For a heavy, slow, economical cruiser like the kind we own now, diesels make a lot more sense.* Relatively low revving, lots of torque, very low fuel use.

Diesel engines because of their heavy construction will supposedly go longer between overhauls but how important that is will be dependent on how many hours you intend to put on the boat.* If you run it a lot and put hundreds or thousands of hours on a boat in a year, diesel probably makes more sense.* If you operate the boat the typical 100-150 hours a year, it will take some twenty or more years to put just 3,000 hours on the engines.* So the theoretically shorter life of a gas engine may not matter at all to you assuming it's suited to the boat and the type of boating you want to do.

Diesels have some safety advantages in that a weepy fuel line or leaking fuel filter won't fill the bilge with easily-ignited fumes.* So you can "get away" with more with a diesel engine.* A diesel engine has fewer systems, the primary advantage being there is no ignition system.* But diesels have their downsides.* They can be hard to start in cold weather.* Service and repairs are generally more expensive although the theory is you don't need to mess with a diesel as much as a gas engine.

So if you factor in all the advantages and disadvantages it's kind of six of one, half dozen of the other.* I would choose one over the other based on what is being powered and how I'm going to use it rather than make a boat-buying decsion solely on a bunch of theoretical safety issues.* A boat's propulsion system is going to be as safe or as dangerous as you make it by your own operation, service, and maintenance practices.


-- Edited by Marin on Wednesday 22nd of February 2012 01:43:28 PM