Which Small Outboard is Most Reliable

[N4RNV]

I have the 2.5 Hp Lehr LP and it is great no carb fouling and runs off a tank of LP (comes with the hose) or the small bottles,(mount right in the top of the motor housing) for portable grills. 2.5 runs 58 minutes at full throttle on a bottle. Happy with mine!

[Dockhead]

Originally Posted by Celestialsailor

Also...I will say while 2 strokes are lighter and simpler in design, they are somewhat inefficient. They have to spin and work harder than a 4 stroke. I know on motorcycles, they only last half as long as their 4 stroke counter-parts.

On motorcycles, you're right -- two-strokes definitely don't last as long. I am guessing that this is a function of cooling, however, on those high specific-output motors.

I don't think you can say this about two-stroke outboards, however, which tend to be slow-running and low stress engines. My 25 horsepower Mariner is 430cc -- so the specific output is only slightly more than my main diesel engine (100 hp out of 2000cc). It's raw water cooled like all outboards, so does not have cooling issues of motorcycles. It redlines at all of 5500rpm. Two stroke engines don't usually rev as high as four-strokes, because they don't need to -- they have twice the power strokes at a given RPM as a four-stroke.

My snowmobile has a very high specific-output two-stroke made by Rotax -- 120 horsepower out of 600cc. It is water cooled, with a snow-to-water heat exchanger in the tunnel. But it only revs to 8000 rpm, and pulls like a freight train from 2000 rpm. The equivalent four-stroke Yamaha revs to 13,000rpm, is I think 900cc, and is nearly double the weight, has an extremely narrow power band, etc., etc. Those Rotax two strokes are extremely long-lived for such a high output motor -- they easily go a couple thousand hours without any service at all other than plugs and cleaning the RAVE valves. Mine is semi-direct injected which overcomes the main disadvantage of two-strokes (see below), and so fuel economy is similar to that of a four-stroke. It is a fantastic engine.

Two-strokes are inherently less fuel efficient than four-strokes, because (a) they need to run richer for cooling; and (b) some part of the fuel-air mixture is wasted out the exhaust during the overlap period of the cycle (unless they are direct or semi-direct injected). This makes them more polluting. But these are just about the only disadvantages I can see -- otherwise, two-strokes are fantastic. The main advantage of them is that a 430cc two-stroke, say, works like an 860cc four stroke, in terms of the volume of fuel-air mixture you can burn on every rotation. Yet they are smaller and lighter than even a 430cc four-stroke.

I guess you can tell that I love two-strokes. I dream about a two-stroke diesel as a main engine -- if someone would modernize the old Detroit Diesel concept.

[S/V Alchemy]

Originally Posted by Curmudgeon

Hi Lin--

I've enjoyed your books.

I have a little Honda 2hp 4 stroke. Always starts in one or two pulls, even after being stored for the Winter. Weighs 28 lbs, sips gas. There is a long shaft version, 20".

I have the same Honda and it is very reliable if you drain the gas prior to layup. I bought it because my small wife can one-arm it off its stand in the forepeak and transom-mount it and because it is air-cooled, meaning it's simpler. It drives three adults in a Portabote at 4.5 knots. It is somewhat noisy, but because it's a four-stroke, it's cleaner.

I find the lack of a neutral gear no hardship. At dead slow, you can simply hold onto a gunwhale or dock with one hand until ready to go. If you need to reverse, spin the engine 180 degrees and flip the tiller arm.

The only retrofit I would suggest is the little adapter so you can run off an external tank. Full out, it will run about an hour on the one litre internal tank, but that would be sufficient for two or three shore runs in most anchorages, I would think.

If Honda made an air-cooled 3 HP that was five to seven pounds heavier, that would be my perfect tender outboard.

[svHannabel]

I've been very happy with our 2hp Honda 4-stroke, though she's a bit noisy being air-cooled. I had to replace the lower unit bearings 2 seasons ago after one of the seals went bad, but it was a $15 part and a fairly easy fix. She's always been a strong runner and easy starter.

[Curmudgeon]

Originally Posted by S/V Alchemy

I have the same Honda and it is very reliable if you drain the gas prior to layup.

I don't even bother to do that. I just top up the tank with new gas each spring and check the oil. Maybe in a few years I'll change the spark plug.

[Chuck49]

I am a Yamaha fan. Very little trouble and easy to work on. Keep blue marine Stabil in your gas, or you can run dry, but the Stabil way is best. Does not dry your pistons and crank out, like you would if you run dry.

[Bash]

Originally Posted by Chuck49

Keep blue marine Stabil in your gas, or you can run dry, but the Stabil way is best.

Interesting. No clear winner as far as engine brand, but strong consensus about Stabil.

[UnlikelyVoyager]

I love my 4-stroke Yamaha. It sips gas compared to my old 2-stroke, runs clean and quiet, and starts every time.

BUT, I do baby it. I always use the yamaha fuel treatments, I have a fuel filter bolted on my transom, and I always run the gas out of it. Never had a carb problem, and I don't think it was luck or karma ;-)

[Celestialsailor]

Originally Posted by Bash

Interesting. No clear winner as far as engine brand...

...Much like an anchor thread...

[Therapy]

Originally Posted by Cheechako

So Monday I put my 9.9 Johnson on Craig's list as I havent use it in 3 years. I just ran it dry before putting it away in the garage. Suddenly I have a buyer an hour after listing it. Arghhh! I have to set it up outside, with a tank, mix fuel and hope it runs imediately before he comes. 3 years, starts on 3rd pull. runs perfectly. Gone.

You didn't ask enough for it.

[Cheechako]

Originally Posted by Therapy

You didn't ask enough for it.

Maybe not, but asked the going rate for a late 90's. However, this one was a "garge queen"... looked brand new. I've found on Craig's list, the new entries are at teh top of the list and disapear fast. You either get a quick deal in the first day or two or not at all. Good if your buying something... look way down the list, hungrier sellers!

[cruise]

we brought a brand Yamaha long shaft 60hp for $10,000 and it didn't last us a year got rid of it and brought a tohatsu 30hp never had a problem best engine ever

[susanna reiter]

Originally Posted by drewzn

I also have the Honda 2hp and have had no issues with it. It starts every time no matter what kind of abuse it gets.

Ditto...

[mangomuffins]

Originally Posted by N4RNV

I have the 2.5 Hp Lehr LP and it is great no carb fouling and runs off a tank of LP (comes with the hose) or the small bottles,(mount right in the top of the motor housing) for portable grills. 2.5 runs 58 minutes at full throttle on a bottle. Happy with mine!

Interesting... How long have you had this engine?
Any other thoughts on these engines anyone?
Price??
Went to their website but dealer locator page was down.


mm

[ohdrinkboy]

as i understand it, the Lehrs are being made in China. I'm not a big fan of chinese made mechanicals. Love the concept of a propane engine.