Diesel or Gasoline

[skipperguy]

My view

3 years with twin cruelsaders 26 years with twin Perkins TD - maintenance about the SAME (see the years of use.....)
Reliability - NO COMPARISON- diesels 4 sure

 

[markpierce]

I love the sound and smell of a diesel engine. Besides, diesels are simpler, and their fuel is safer.

 

[Mark Laurnen]

There is so much technical expertise on display that this site is truly invaluable. On a much lower mental plane, I would vote for diesel. Nothing is fireproof, and nothing is foolproof. HOWEVER, having lost a family boat (Tollycraft 24’), and very nearly my father, after everything was “done right” in a mishap years ago ... my surviving dad went diesel and so have I. He had stopped at the fuel dock upon retuning from a fishing trip, closed the cabin and refueled, blown out the bilge and restated the engine, moved to the mooring slip and shut down, the explosion occurred when he turned off the battery switch ... it seems there may have been an unknown leak at the top of the tank. Despite an extensive insurance investigation, the definitive diagnosis went down with the boat. Diesel burns ultra hot, but at least it doesn’t flash under normal circumstances. As always, diligence and caution pay big dividends, but nothing (worth doing!) is completely safe!

 

[rcsomany]

... I realize there is always the potential for an exploision with gasoline, but is it that a major consideration?

https://www.cheknews.ca/north-saani...ad-to-fuel-dock-cause-remains-unknown-668534/

This was an experienced owner/skipper in familiar surroundings and circumstances.

Although it may or may not have been a contributing factor, I found this behaviour of gasoline vapour to be more than frightening:
"The lower flammable limit or lower explosive limit (LFL or LEL) of gasoline is 1.4 percent; the upper flammable limit or upper explosive limit (UFL or UEL) is 7.6 percent. This means that gasoline can be ignited when it is in the air at levels between 1.4 and 7.6 percent. A concentration of gasoline vapour in air below 1.4 percent is too "lean" to burn. Gasoline vapour levels above 7.6 percent are too "rich" to burn. Flammable limits, like flashpoints however, are intended as guides not as fine lines between safe and unsafe."
(https://www.ccohs.ca/)

 

[backinblue]

Glen, welcome to the world of power boating where you're not always adjusting lines and sheets; you get your course and speed set, turn on the autopilot and just enjoy the day.

I think what Arc meant by his comment is that diesels have much larger props because they have much more torque. You'll find when you're docking a diesel boat that you put the shifter in gear for just a second then wait as the boat responds. It truly is fun to back a diesel boat into a slip or up to a dock.

While powering is less work than sailing, it's not automatically more enjoying. Powering will likely get you there sooner, but whether it's more fun is subjective.

 

[sunchaser]

In the active Fleming thread a recent fire took down a diesel F55 in NZ. It would seem lack of maintenance and electrical issues are normally the culprit in fires.

With diesels outnumbering gas on TF by at least 10:1 the answer between the two is obvious. A read of Boating magazine and a trip to your local rack storage site will yield a 10:1 margin for gas.

It all comes down to your boats mission. If one chooses to do what most of us long distance cruisers do, hauling what amounts to a house around, the answer is diesel. We spent decades boating inland, gas vessels are the norm by far. Cruising salt water and longer trips diesels reign.

In my younger days I sailed out of Manhassat Bay Long Island. The Atomic 4 gasser was the norm SV auxiliary. Once small but heavier diesels became common their greater weight required a redesign of keels and ballast locations. With diesel's better economy sailing became less common in light airs and the term iron maiden became apt.

In the PNW sail boats with no sails up are the norm and a very efficient way to get somewhere given their slippery hulls. So for a boat of choice and frugal expenditures many boat owners prefer sail boats. These types have their own popular forums.

Not to mention that ocean crossers are seldom power boats and mostly diesel powered SV. So, back to the OP's mission

 

[backinblue]

In the active Fleming thread a recent fire took down a diesel F55 in NZ. It would seem lack of maintenance and electrical issues are normally the culprit in fires.

With diesels outnumbering gas on TF by at least 10:1 the answer between the two is obvious. A read of Boating magazine and a trip to your local rack storage site will yield a 10:1 margin for gas.

It all comes down to your boats mission. If one chooses to do what most of us long distance cruisers do, hauling what amounts to a house around, the answer is diesel. We spent decades boating inland, gas vessels are the norm by far. Cruising salt water and longer trips diesels reign.

In my younger days I sailed out of Manhassat Bay Long Island. The Atomic 4 gasser was the norm SV auxiliary. Once small but heavier diesels became common their greater weight required a redesign of keels and ballast locations. With diesel's better economy sailing became less common in light airs and the term iron maiden became apt.

In the PNW sail boats with no sails up are the norm and a very efficient way to get somewhere given their slippery hulls. So for a boat of choice and frugal expenditures many boat owners prefer sail boats. These types have their own popular forums.

Not to mention that ocean crossers are seldom power boats and mostly diesel powered SV. So, back to the OP's mission

I've not heard the "iron maiden" term, but "iron jib" is commonly used. Sailboats with no mast are an efficient way to get up and down the AICW.

 

[FF]

On the other hand the number of gas boats is 100-1 compared to diesel ,and they all don't seem to be exploding fire traps.

The real need for a diesel is the perhaps 20% better fuel burn which allows a longer range than a gasser.

Price wise a new Crusader engine costs less than a half dozen diesel electric injectors , or gasp ! a black box.

For a few hundred hours a year gas will work just fine.4,000 hours as a cruiser compared to double that in diesel.

NYC to Bermuda to Venz. for cheap fuel is better with a diesel.

Just an ICW or the loop, gas wins on cost and quiet aboard.


"Make a list , check it twice." Be realistic .

 

[Hippocampus]

There are more BTUs per unit volume with diesel. So less space is required to get the same range. The typical service life of a diesel is greater especially if sleeves can be removed. So beyond the issue of needing to run blowers and have everyone on your case as you are slow when fueling diesel wins hands down for cruising boats. Even if exclusively coastal or on inland waters going to the fuel dock is time consuming and a PIA. Most of us are either time constrained or full time cruisiers. In either case don’t want to waste time fueling or limiting our plans due to need for a fuel stop.

 

[JLD]

My opinion my be contrary to many of those posted here, but unless you plan on cruising hundreds of hours in a single season, it really doesn't matter if the engines are gas or diesel. There are pros and cons to both. Long range cruising, I think diesel is a better option, but to be honest, many folks do NOT do long range cruising.

There are few individual model of boats where you will have a choice of gas or diesel for the same model boat. Personally, I would find a boat model (could be a trawler or other type) that fits your cruising dreams. I think the most important feature for the boat are size, layout, condition, and budget.

Jim

 

[rslifkin]

There are more BTUs per unit volume with diesel. So less space is required to get the same range. The typical service life of a diesel is greater especially if sleeves can be removed. So beyond the issue of needing to run blowers and have everyone on your case as you are slow when fueling diesel wins hands down for cruising boats. Even if exclusively coastal or on inland waters going to the fuel dock is time consuming and a PIA. Most of us are either time constrained or full time cruisiers. In either case don’t want to waste time fueling or limiting our plans due to need for a fuel stop.

The fuel burn and range thing is the big reason I'd love a good set of diesels in my boat. As-is with the gassers, at 17 - 18 kts, it gets slightly better than 0.5 nmpg. At 6.5 - 6.7 kts, it's more like 1.2 - 1.3 nmpg. Good diesels would improve that to around 0.9 - 1 nmpg on plane and somewhere around 3 nmpg at 6.5 kts, as best I can determine.

 

[GFC]

Geesus Guys, give the OP a break. He was asking fairly basic questions. I don't think he was asking for an encyclopedic discussion of burn rates, etc. This thread has turned into an "I'm smarter than you are" thread.

Give him a break.

 

[SteveK]

My opinion my be contrary to many of those posted here, but unless you plan on cruising hundreds of hours in a single season, it really doesn't matter if the engines are gas or diesel. There are pros and cons to both. Long range cruising, I think diesel is a better option, but to be honest, many folks do NOT do long range cruising.

There are few individual model of boats where you will have a choice of gas or diesel for the same model boat. Personally, I would find a boat model (could be a trawler or other type) that fits your cruising dreams. I think the most important feature for the boat are size, layout, condition, and budget.

Jim

excellent summary. I will add that gas powered boats seem to be designed for faster speeds than diesel powered, generally speaking.

 

[rslifkin]

excellent summary. I will add that gas powered boats seem to be designed for faster speeds than diesel powered, generally speaking.

In newer stuff, that seems to be less of the case. In older stuff, absolutely. At least up to the 35 - 40 foot range, most older gas boats are faster than their diesel cousins. But I think it really goes the other way around. Not that gas boats are faster, but that faster boats are gas. In that size range, a lot of the older diesels available were big and heavy relative to their power output, especially compared to the available gas engines. So the gassers fit the performance goal better and in they went.

Modern diesels have closed that gap quite a bit, so the distinction seems less significant, or at least the overlap and crossover happens at a smaller boat size.


As an example, my boat had 2 engine choices. 340hp gas 454s, or 230hp Volvo diesels. The diesels were not only way down on power, but also added 2000 lbs to the boat. So you ended up with a boat that could cruise at 15 - 16 kts (just on plane with the extra weight) at max continuous and might break 20 kts on a good day. Compared to the gas version that would comfortably cruise 18 kts and could do a bit more at max continuous, with a WOT speed around 27 - 28 kts. There's a reason I've only ever even heard of one with diesels and pretty much everyone went for the gassers.

 

[SteveK]

That Chris Craft hull is made for speed, so gas go fast engines are appropriate. I would hate to be an owner with the go slow diesels when a sister ship goes flying by.
I will go out on a limb and say it is not a trawler as it was not meant to run at calculated hull speed

 

[rslifkin]

That Chris Craft hull is made for speed, so gas go fast engines are appropriate. I would hate to be an owner with the go slow diesels when a sister ship goes flying by.
I will go out on a limb and say it is not a trawler as it was not meant to run at calculated hull speed

I absolutely agree on the not a trawler part. It does a pretty good job of pretending to be one, but it's definitely not. It's far better than a typical express cruiser type at going slow due to bigger rudders and having a keel, but like any planing hull, there are conditions where you're better off speeding up. And when you do speed up, it's more like an old Hatteras (meant to run in the high teens) than an express cruiser or fast sport fish (where 20+ kts is normal). This hull just isn't meant to ride or handle well in anything other than glassy smooth water once you start to push the speed.

 

[TowLou]

To live on or go out for extended voyages I would go diesel hands down.

It is a simpler system to run, especially you have a older mechanical diesel. No ignition system to fail. Fuel is more stable then gas.

If for a day cruise or to use now and then I would go either way. Still leaning on diesels but if a gasser came up for the right price at the right time looking good it could take up some of my time.