outboard vs inboard

[Harold B]

I am not a know it all so I will kind of follow success rather than reinventing the wheelbarrow. The soulution for your desire for a durable safe comfortable inexpensive vessel is a powered dory like the Saint Pierre Dory and it is simple to customize to meet personal requirments and with a small marine engine will get a three to four hundred mile range. The only unmet requirment is the greater speed you desire but that isn't as bad as you might think because most times when boats are in open water they are usually slowed down so that they are a bit more comfortable but the dory design is faster in hard weather. Ten horse power will push a 22 foot dory at a steady 7 to 8 knots with an inboard or an outboard in a well. I had a dory (power) for many years and it was safe and sound just not to fast but I moved inland so we parted company. Consider a dory and if you can't improve on the idea go with a Swampscott dory rather than a Banks dory or the great grandad a St Pierre dory

[FAST FRED]

" There must be some point where the advantages of the inboard overcome the disadvantages as size and weight goes up and area of intended use expands."

One huge disadvantage to the outboard is most get their HP rating with massive complexity.

Electronic everything , super light weight construction and HP delivered at 5000 rpm would not be my first choice for longevity.

A basic inboard , with little complexity would be far easier to live with long term.

If a 25HP Honda OB meets your needs , a 4 cyl 25 HP Wisconson might also .

[Wavewacker]

I think everyone in this thread knows more about the subject than I do, but that doesn't stop me from throwing this out.....My vote is for an I/O, a Merc Cruiser 140 would get you around, not at a blazing speed....you guys can figure the speed out. One, you can find these pretty cheap, I got rid of a whole boat for $600 and there wasn't anything wrong with the old Chevy 4 banger, they were used in the old Nova and are bullet proof. The I/O will be cheaper to maintain and repair with the lower unit than getting to a tranny inside. Mine wasn't 5000 pounds, you might opt for the V-6. I got great milage out of the 4 and not bad at all out of a cuddy with the 6.

I'm planning on an OB, 25 to 50hp on an efficient hull design yet to be discovered, 25 to 30' but I'm in no hurry, I want economy. Winterizing boats in my area take the fun out of it, I use to go on Jan. 1 and had to re-do the system when we got home.....old stuff. The OB can be taken off and taken into the garage and forget about it! If it needs maintenance, toss it in the truck and go to the shop. If it crashes and burns, throw it away and get another one, cheaper than getting a new(er) inboard and having the engines swaped out for those who don't do that stuff.

You can get heat off an I/O, off the block, but not as efficient as a closed system and I never did it.

I'd think larger OBs would not be cheaper in the long run on a 6,000 pound V, not sure what a 200 hp is I'd guess at 15K here as opposed to a 50hp for 5,500 or 3K for a 25hp. Just saying, long term use I'd plan on a replacement for OBs. 2cents....

[Wavewacker]

Man, talk about killing a thread! Looks like I killed the entire topic!

[hoytedow]

You did well, Grasshopper.

[Submarine Tom]

You just can't beat directable thrust, power trim/tilt, ease of installation, good power to weight ratio, broad operating RPM range, etc., etc.

[Wavewacker]

Does anyone know of any study that looks at the longevity of outboards, how many hours to an overhaul at different makes and hp?

I have seen estimates for diesel engines, if there is such a study then a better comparison can be made to the costs per hour or terms of service.

[michael pierzga]

Big Suzuki 250...well maintained, commercial duty, sea water service.. at 2200 hrs 4 years .... extensive heat exchanger corrosion, engine mounts shot, electric wire harness chafe problems...

engine replaced on recommendation of Suzuki dealer.

[Wavewacker]

Originally Posted by michael pierzga

Big Suzuki 250...well maintained, commercial duty, sea water service.. at 2200 hrs 4 years .... extensive heat exchanger corrosion, engine mounts shot, electric wire harness chafe problems...

engine replaced on recommendation of Suzuki dealer.

That seems to qualify my opinion above, what was that, 4 or 5k$ a year to salvage? A larger OB being more expensive, what about smaller enigines, popular for sailboats, the 9.9 or up to a 25hp.

But, I suppose to be fair you need to look at hp to hp. I'm just thinking that small OBs can be cheaper in the long run, say 10 or 15 years out.

[michael pierzga]

Outboards have a special purpose. High output, compact, and cheap.

When you select a powerplant, only you will know what is the best choice.

Small outboards for tenders provide reliable service for many years.

Hopefully within the next fews year small gasoline outboards become obsolete, being replaced by electric outboards.

[dskira]

Electric is the magic word. the reality is:
Very heavy due to batteries
Absolutely NO range
Long time to recharge
Outrageously expensive
Extremely complex for self reliance
Unsuitable for adverse environment (salt water)
DC current dangerously high.
Cooling problem.
Electric is just the new scam, since the batteries are the weakest link.
Its like saying: Steam, not mentioning the weakest link, the steam generator.
Before the outboard with small internal combustion engine become obsolete, the Sahara will be a golf course.

[tom28571]

Originally Posted by dskira

Electric is the magic word. the reality is:
Very heavy due to batteries
Absolutely NO range
Long time to recharge
Outrageously expensive
Extremely complex for self reliance
Unsuitable for adverse environment (salt water)
DC current dangerously high.
Cooling problem.
Electric is just the new scam, since the batteries are the weakest link.
Its like saying: Steam, not mentioning the weakest link, the steam generator.
Before the outboard with small internal combustion engine become obsolete, the Sahara will be a golf course.

Pretty good bet.

[Fanie]

Originally Posted by michael pierzga

Hopefully within the next few years small gasoline outboards become obsolete, being replaced by electric outboards.

Nah ! Permanent magnet motors running by themselves, no external power or fuel required. Lightweight and powerful.

[Willallison]

Ah yes... the old prepetual motion machine.... can't wait...

[Easy Rider]

I haven't read the whole thread but I don't think any or much consideration has been given to good balance. Unless you have a boat w a very small engine compared to it's size the weight of of an outboard at/on the stern ruins many many designs. I've been thinking of building a wood boat rather long and narrow and have thought very highly of the Atkin boats including his/their flat bottomed designs. I do want an OB but after much reflection I think these boats (designed as inboards) wouldn't ride and handle all that well. The semi-disp mid speed boat seems to me to need the weight concentrated in the center of the boat. And after these thoughts I've decided the old inboard boats have weight distribution and balance that can't be achieved with OB or IO power on many hulls. To what extent would this thinking apply to modern boats designed for the weight of their power plants to be in the stern? I've often thought the ideal boat may be an IO with the engine amidships driving the leg with a connecting shaft. I have seen a 35' diesel commercial boat built this way. But only one.