Outboard trawlers

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There is a myth that you can't get CO poisoning from diesel exhaust. Granted the amount of CO in diesel exhaust is less than from gasoline exhaust, there is still CO present. And it can still kill you (maybe just not as fast).

https://www.ncbi.nlm.nih.gov/pubmed/18643868

https://www.overdriveonline.com/in-cab-diesel-fumes-separating-carbon-monoxide-fact-from-fiction/

ss - Interesting couple of reviews. Thanks

That opens my eyes better to "potential" [however small it may be] of CO from diesel fuel as being a dangerous enough content to cause death.

Albeit, as second link eludes: For CO in dangerous amount from burned diesel would need to be exacerbated by very badly tuned engine and exhaust entering a considerably air tight location. Seems that engine running to mfg specs would create only very small amount of CO... not enough to be dangerous

Statement toward end of first link [regarding diesel trucks]: "Lastly, an extensive literature review produced no scientifically reported cases of fatal CO poisoning attributed to diesel fuel exhaust."
 
One of the strangest vessels I saw last year was a pretty large sailboat, with no mast or rigging. It had a 70hp or so outboard mounted on a bracket/swim platform. It was cruising at a pretty good clip. The captain looked to be 7 ft tall, he was huge.

When they hit my wake (not a huge wake by any means) the boat went wonky, the big guy almost lost his footing, and the roll was incredible. I guess sailboats are meant to be pulled not pushed.
 
One of the strangest vessels I saw last year was a pretty large sailboat, with no mast or rigging. It had a 70hp or so outboard mounted on a bracket/swim platform. It was cruising at a pretty good clip. The captain looked to be 7 ft tall, he was huge.

When they hit my wake (not a huge wake by any means) the boat went wonky, the big guy almost lost his footing, and the roll was incredible. I guess sailboats are meant to be pulled not pushed.

While it may be hard to imagine, the mast of a sailboat adds a lot to its stability even with out the sails up
.

Ted
 
"I guess sailboats are meant to be pulled not pushed."

A more accurate concept,

"While it may be hard to imagine, the mast of a sailboat adds a lot to its stability even with out the sails up"

Yes, fishing schooners working the Grand Banks would hoist an anchor part way up a mast to slow the roll.
 
In my poor addled, feeble mind, the forward open cockpit may SOUND like a good idea until the weather goes down hill then, everyone wants to go aft for some protection. Why not just cap it and make it part of the below deck space.
 
ss - Interesting couple of reviews. Thanks

That opens my eyes better to "potential" [however small it may be] of CO from diesel fuel as being a dangerous enough content to cause death.

Albeit, as second link eludes: For CO in dangerous amount from burned diesel would need to be exacerbated by very badly tuned engine and exhaust entering a considerably air tight location. Seems that engine running to mfg specs would create only very small amount of CO... not enough to be dangerous

Statement toward end of first link [regarding diesel trucks]: "Lastly, an extensive literature review produced no scientifically reported cases of fatal CO poisoning attributed to diesel fuel exhaust."

I thought the Nazis used submarine diesels to gas people as well as gassing vans before they switched to ZxyklonB? I’m pretty sure the science is documented on that...... The vans might have been gasoline but the sub motors were certainly diesel. And they killed 10’s of thousands with them.
 
I thought the Nazis used submarine diesels to gas people as well as gassing vans before they switched to ZxyklonB? I’m pretty sure the science is documented on that...... The vans might have been gasoline but the sub motors were certainly diesel. And they killed 10’s of thousands with them.

A friend of my brother almost lost 2 of his kids, the big aft door was open on his diesel powered cruiser, kids down in the boat, the kids got real quiet, father came down from the fly bridge to see them overcome with diesel CO. He used the VHF to seek medical help from a doctor on the water. The kids were fine after being move to the fresh air while waiting for the medical help to arrive.
He eliminated the future problems by installing a household CO detector to supplement the standard detector.
Based on that example, I installed a household detector. They now have detectors that are sealed and advertised to have 5 years batteries.
 
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For many years I had heard diesel exhaust was not so much filled with CO to bother to worry too much about it; unlike gasoline exhaust that holds much CO and to be very worried. Now, I hear that diesel fuel exhaust, although with less CO content than gasoline, is also dangerous and could kill under some conditions.


Can't help but to wonder annual fatality-count from diesel exhaust fumes as compared to gasoline exhaust fumes?? Anyone know easy way to find stats on this comparison?
 
Even if you found those numbers, I'm not sure they would have much relevance, unless you also had the number of people exposed to gas fumes compared to diesel fumes.

If there were 100 times more gas fume deaths than diesel fume deaths, it sound like gas engines are so much worse....but if there are 100 times more gas engines than diesel engines....the risks might be the same.
 
Even with perfect combustion you can exhaust products that can kill you. While you are unlikely to drown from the water produced, you could succumb to the CO2 if it collects in the area you are in (e.g. berth compartment, engine room).

A CO2 concentration of 20% is likely to kill most people.
 
Even with perfect combustion you can exhaust products that can kill you. While you are unlikely to drown from the water produced, you could succumb to the CO2 if it collects in the area you are in (e.g. berth compartment, engine room).

A CO2 concentration of 20% is likely to kill most people.

We've been talking about CO...

Both CO and CO2 are measured in ppm.
 
Even if you found those numbers, I'm not sure they would have much relevance, unless you also had the number of people exposed to gas fumes compared to diesel fumes.

If there were 100 times more gas fume deaths than diesel fume deaths, it sound like gas engines are so much worse....but if there are 100 times more gas engines than diesel engines....the risks might be the same.

So true!


Stats on all levels would be required to get clear picture of relevant %age circumstances.
 
I've been through the "diesel exhaust is innocuous" debates on TF before. In general, diesel exhaust carries very low CO levels, with gasoline engines way higher. I don't have numbers near at hand, but it's orders of magnitude I recall.

The problem with researching CO casualties is a many headed hydra. Evaluate by marine exposure? General industry? Then, I doubt if much info is detailed as to CO source - home HVAC? Garage suicide?

I have reviewed (for work) 2 industrial accidents where multiple deaths occurred due to contaminated supplied breathing air systems. Coroner ruled CO. There were several other factors, but the investigations (law enforcement, OSHA, insurance) all concluded that the berating air systems compressors were sourcing sufficient CO from heavy equipment diesel exhaust upwind of the intake.
 
That was breathing, not berating.
 
That was breathing, not berating.

Don't mean to be berating the breathing of gas or diesel engines... just seams to me that if those two power plants and we simply do not breath the same airflow from beginning to end that the berated result of death would not occur. For that incidence I [we all] could breath EZ! :thumb:

Be careful of CO gathering in air in to high ppm from any source. :facepalm: :ermm: :nonono:
 
There is a very good reason Diesel engines are used in underground mines while gas engines are not. Diesels produce far less CO than gasoline engines. Diesels (compression engines) operate in a lean burn condition or high intake air volume as compared to petrol engines which operate in a near stoichermetic condition.

In underground mines an air testing device such as a Drager tester is a normal workday tool. In a freshly blasted rock heading a large ventilation fan will quickly evacuate blasting related nitrogen gases. The diesel trucks and loaders begin mucking out the broken rock. With adequate ventilation CO will begin to slowly rise, but not to a dangerous level. Then onto the next heading, all very safe.

No way would a gasoline powered loader work due to CO levels alone in an underground mine. Not to mention engine output, longevity and fuel efficiency.

A normal diesel exhaust will emit (at tailpipe) approximately 1500ppm or less CO whereas a gas engine will be in the 10,000 ppm range but climb to 60,000 when the accelerator is pushed down.

Catalytic converters change this situation. A finely tuned gas engine with fuel injection, turbos and catalytic converters can commonly achieve less than 100 ppm CO. But a normal inefficient small gas genset on a twin hulled houseboat (air trap for swimmers) has all too often proved deadly. Or likewise a chainsaw, lawnmower, outboard, leaf blower etc.

None of this is rocket science, just workplace conditions 101 for underground miners. Unfortunately for those contemplating suicide with a diesel in the garage, you'll get very sick rather than dead. Living a vegetable state life for a long time, or at best stuck reading TF forever. :eek:
 
No question, this is a trend. Sea Ray is offering more and more, larger boats with outboards. MJM announced the 53z at the Palm Beach show with four Mercury’s. There were a LOT of boats showing off new outboard tech in Palm Beach.
 
No question, this is a trend. Sea Ray is offering more and more, larger boats with outboards. MJM announced the 53z at the Palm Beach show with four Mercury’s. There were a LOT of boats showing off new outboard tech in Palm Beach.

Ditto Formula with 4 300 HP outboards on their fishing machine. And Tiara with 3 - 350 HP outboards on their new 37.
 
No question, this is a trend. Sea Ray is offering more and more, larger boats with outboards. MJM announced the 53z at the Palm Beach show with four Mercury’s. There were a LOT of boats showing off new outboard tech in Palm Beach.




four Mercury’s could anyone hate themselves that much ???
 
A nice advantage of multiple outboards is joystick maneuvering. Forward, back, pivot, translate, station keeping, all in one little stick. Kind of interesting to watch multiple motors all doing their own thing while moving a boat.
 
A nice advantage of multiple outboards is joystick maneuvering. Forward, back, pivot, translate, station keeping, all in one little stick. Kind of interesting to watch multiple motors all doing their own thing while moving a boat.

Yeah, I watched one of those systems at work last year. Guy brought his high HP multi outboard boat down a slip way, spun it 180 degrees and walked it sideways into the dock. Impressive bit of 'magic' by the control system of those outboards. But they were working their guts out screaming at each other. I would have been a lot more impressed by a skilled boat handler making the same docking with a lot less throttle and stress and strain on the motors.
 
" I would have been a lot more impressed by a skilled boat handler"

Skilled boat handling requires more than a charge card.
 
Jumping in to earlier thoughts. Yanmar now makes 50 hp turbo diesel outboards. You wonder how a pair (or more) of these would do powering a trawler designed from the ground up to use them.
https://newatlas.com/yanmar-dtorque-111-turbo-diesel-50hp-outboard/51675/

For those who are worried about losing swim platform space to outboards, Sea Ray has a covered outboard design. Again, the boat would need to be designed at the outset to take advantage of these two ideas.
http://www.searay.com/page.aspx/pageid/160944/pmid/334210/370-Venture.aspx
covered outboard.jpg
 
Jumping in to earlier thoughts. Yanmar now makes 50 hp turbo diesel outboards. You wonder how a pair (or more) of these would do powering a trawler designed from the ground up to use them.
https://newatlas.com/yanmar-dtorque-111-turbo-diesel-50hp-outboard/51675/

For those who are worried about losing swim platform space to outboards, Sea Ray has a covered outboard design. Again, the boat would need to be designed at the outset to take advantage of these two ideas.
Sea Ray 370 Venture | Sea Ray Boats and Yachts
View attachment 74581

All the big houseboats for rent on Lake Mead use outboards. They are tucked underneath the back and unless you look at the boat from a distance you cannot see them. They do not hang on the back of the boat and get in the way.
 
Well my high speed trailered outboard trawler, while its still a work in progress is doing what its designed to do. If a person does not need an ocean liner, there is no reason not to go the alternative route. In the smaller boats it surely saves a lot of room inside that you loose with an inboard for sure. There I no creek that I will have a problem going in for nothing more than anchoring and bird watching.:thumb: Different strokes for different folks,, step right aboard folks.
 

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I opened the link... here is what photos show:

"We Research The Effects of Rum During a Hurricane" is printed on transom in place of a boat name. Both Mercury outboards have "Rumicane" printed on their cowlings sides in place of the brand name Mercury. The word "Rum" is printed on the cowlings' front. One photo shows an outboard toooo close to what looks like a concrete dock [potential calamity]. I've gotta wonder if the owners are practicing alcoholics?? - I'm just kidding... sorta!

I am not impressed with outboards added on to relatively large older boats that were not originally design-balanced to loose couple thousand pounds amidships and not designed at all to have many pounds fully cantilevered off their rear. With that said... I can wholly support relatively large new boats that are specifically designed to have outboards as their means of power. I'm confident that OB power locations can become well enough designed into boats so that the engine do not need to be hanging off the stern in harms way of so many different particulars and potential damage circumstances. Anyway... with engines off the rear... landing fish is totally interrupted and the swim step [even if a greatly shortened one can be between twin OBs] becomes pretty much not available for any type of efficient use at all.

I would like to know what cruising speed is and nmpg at cruise speed for this heavy construction 1967 Pearson brand boat with two 35 horse OBs. I also wonder same stats for WOT.
 

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