Dinghy / Two- or Four-Stroke Outboard ?

[PamlicoTraveler]

Originally Posted by MichaelC

Definitely two stroke. One with each oar, simultaneously. Quiet, healthful, never lets you down.

It does have its advantages, but I'm way too lazy - plus I have an inflatable floor and it doesn't row well.

[Jim Cate]

Originally Posted by daddle

Never seen a cruiser do a fresh water flush

Why Daddle, I'm a cruiser, and I regularly flush out our dinghy outboard... every time we go far enough up a river to get to fresh water!!

But my last Suzuki only lasted 12 years... and then some bastard nicked it in Hobart!

AS to the 2-stroke/4-stroke issue, the simplicity of the 2-stroke and the subsequent lack of maintenance needs far outweigh the fuel economy gains IMO. The modern ones are simply unbreakable, even by a cruiser!

Cheers,

Jim

[marc2012]

I have a stroke yamaha and it runs so quiet you can not hear it.Wait a min. it usuallay requires about .5 hr of work to start.Don't know which idiot designed it but VERY difficult to work on.marc

[beau]

Small 2 stroke outboards Mercury, Nissan, Tohatsu are all the same motors made by Tohatsu and rebadged.
My 3.3 starts first or second pull every time, and I don't starve the fuel, that is you problem, you only do that if you are moving the motor or storing it.

[Dame.n.Jess]

Originally Posted by beau

Small 2 stroke outboards Mercury, Nissan, Tohatsu are all the same motors made by Tohatsu and rebadged.
My 3.3 starts first or second pull every time, and I don't starve the fuel, that is you problem, you only do that if you are moving the motor or storing it.

While its true the motors are all re badged Tohatsu's its not true that starving them of fuel is wrong or ab-normal. in the owners manual it says to turn the fuel off and wait until the motor stops as this removes the chance of the petrol evaporating and then allowing the two stroke oil to cause the carb to become fouled up.

We use a 3.3 as a daily commuter boat when you go to start your motor first thing after you have run it out of fuel previously turn the fuel on open the tank vent and hold the motor up (ie; handle down) while its mounted to your transom as this allows the fuel bowl in the carb to fill up with fuel again.

Then proceed to start, all motors are different in what they like first start, our new 8hp merc like 1/2 choke one or two pulls then choke off straight away. Our 3.3 like 2/3 choke and one good strong pull then choke down to 1/3 for about 30 seconds.

These motors are great simple motors and not much has changed in their design for over 20 years now.

I rebuilt our 3.3 after I ran it to many times without oil in the fuel (bad memory, just plain forgot to put it in) and other than some minor bore scuffs there was almost nothing wrong with the internals, they are a strong motor, reliable and worth spending some time and effort fixing if there is any issues with them.

[s/vfootloose]

Check with some large dealerships. The dealer I spoke with last year had some 2 strokes and told me they could sell a certain amount based on how many 4 strokes they sold. Don't know if thats still true.

[marc2012]

I would ck on honda,air cooled 4 stroke.marc

[Highlander40]

Evinrude produced a video showing identical boats with same HP outboards.
One withE-tech 2 stroke, the other a Yamaha 4 stroke.
They tied them together with a rope for a tug of war.

The 2 stroke pulled the other boat backwards so fast that it sank!

[CSY Man]

I had a 4 HP, 2 cylinder Evinrude for years, but it finally died.
Suspected methanol in the fuel to be the culprit.

At full power the Evinrude would push the dink at 7,5 knots.

Replaced it with a brand new Yamaha 4 HP. (bought on ebay from a Florida dealer at a substantial discount)

The 4 stroke will push the same dink with the same load at 10,8 knots.
Much more powerful than the 2 stroke..No idea why, 4 HP should be the same regardless of brand...

The Yamaha weighs in at 48 lbs and the Evinrude was 29 lbs.

Very happy with the Yamaha despite the extra weight.

[READY2GO]

I have a 20 year old Johnson 2 stroke 2 hp for the dink. It starts first or second pull. I would say your starting problem is with running it dry, not that it is a two stroke. I only run our dry when I store it below. It would take weeks for the gas to evaporate and leave oil in the carb. If you use it at least once a week just shut it off.

[easterly38]

I would stick with a 2-stroke if possible. I would stay away from Mercury if possible. I have a 9.9 Merc 4-stroke, that I've whined about before, and it has spent more hours in the shop than on the water in the last five or so years since I bought it. Didn't work properly right out of the box.

So far as your starting issue goes, might want to try hooking up the fuel line and pressuring it a little while before you use it. I had the same issue with my Johnson 2-stroke for a while. I started connecting it and pumping the fuel line about 15 minutes before I needed to crank it and problem was solved. Have no idea why, but it cranks on the first or second pull every time. (That works for me, might be a PITA for some folks, though.)

As stated earlier, 2-strokes are not outlawed in the US. There are several being manufactured and sold by Merc and Evinrude, but only in the larger models. I have no idea why they aren't available in the smaller models unless there is no way to make smaller 2-strokes meet the new emissions requirements or if there is no way to do it and still meet a reasonable price point.

So far as actual horsepower goes, a 4 horse 2-stroke puts out the same power as a 4 horse 4-stroke, if they are both in good condition....horses is horses. One difference is a 2-stroke responds a little faster, as you've already heard. Another is that a 4-stroke is generally heavier, so it is pushing a little more weight and in theory, won't push the boat as fast...though I'm sure the difference in speed is negligible.

Another thing I've heard is that 4-strokes don't foul plugs as fast as a 2-stroke. I use both and if this is true, I sure have not noticed it.

Maybe some of this will help you out.

[PamlicoTraveler]

It sounds like the fuel starvation is definitely not necessary. I have been doing it to keep the carb from getting fouled, but that's probably part of the problem.

[GordMay]

Originally Posted by Highlander40

Evinrude produced a video showing identical boats with same HP outboards.
One withE-tech 2 stroke, the other a Yamaha 4 stroke...

Evinrude E-tec vs. Yamaha:

➥

http://www.youtube.com/watch?v=_-7I00cZUE0

➥

http://www.youtube.com/watch?v=1XRCDN3JKZ0

[Dockhead]

Originally Posted by easterly38

I would stick with a 2-stroke if possible. I would stay away from Mercury if possible. I have a 9.9 Merc 4-stroke, that I've whined about before, and it has spent more hours in the shop than on the water in the last five or so years since I bought it. Didn't work properly right out of the box..

I've heard a lot of bad things about Mercury outboards, so there must be something to it. All I can say is that I have had several and they have all been flawless. Had Mercury 15 horse and 5 horse two-strokes on the dink on the old boat; both perfect (changed to the 5 horse because of the weight). Still have a 40 horse Mercury 4-stroke on our lake boat. Works flawlessly for five or six years by now. Guess I have been lucky.

Originally Posted by easterly38

One difference is a 2-stroke responds a little faster, as you've already heard.

Every cylinder in a two-stroke engine produces power once per revolution, instead of every other revolution like a four-stroke. So two strokes tend to have more torque and tend to develop their power at a lower RPM, compared to a similar four stroke.

[CSY Man]

So far as actual horsepower goes, a 4 horse 2-stroke puts out the same power as a 4 horse 4-stroke, if they are both in good condition....horses is horses. One difference is a 2-stroke responds a little faster, as you've already heard. Another is that a 4-stroke is generally heavier, so it is pushing a little more weight and in theory, won't push the boat as fast...though I'm sure the difference in speed is negligible.

Agreed, HP is HP, that is why I am curious why the Yamaha 4 is considerable more powerful than the Evirude 4:

A 3 knot difference in top speed should equal one or two HP...?

Any other Yamaha 4 owners have the same (pleasant) experience?

It should be mentioned that the latest model of Yahama 4 is a different animal and it shares the innards with the 6 HP and weighs more..My model was new in 2009 and as far as I know, only comes as a 4..