• 2-stroke motors, huh??

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Talk about your boats, trailers, and boating specific topics here. Sponsored by Life Proof Boats.
 #246349  by The Quadfather
 Mon Feb 11, 2019 9:26 am
I am just curious in the modern day of 2019, what are people’s thoughts of owning a 2-stroke motor?

I was looking at a pretty nice boat, all things considered... except it comes with a “Low-hours”. 2006 Evinrude 2- stroke. I come from a 4-stroke EFI motor background. The whole thought of mixing gas/oil, just sounds like a PIA. Is there anybody out there who actually has a reason to go this route? Please tell me your reasons.
There will be people who have just owned boats with 2-strokes, who do not choose to upgrade, cost, etc.
But if you are coming into it for the 1st time... seems like a total dud thing to have hanging off transom when trying to sell a boat.
But maybe I’m missing something here?
 #246351  by fisherman92
 Mon Feb 11, 2019 9:48 am
Not sure why to specifically have one besides they're less expensive typically, maybe some others have reasons why..? I have friends with them and they dont mind them. In my experience of having 2 strokes and being on boats with them is they are just a bit more of a pain like you said haha. Typically harder to start, smoke more, mixing oil, ect. Also, there are watersheds/ fisheries that are not allowing them anymore. I have a 4 stroke now that has a carb that works great, 1999 Honda 90 hp. But next motor will for sure be a 4 stroke EFI motor.
 #246355  by 18ftTrophy
 Mon Feb 11, 2019 11:01 am
Hey Chris, Don't discount the Evinrude E-tecs. They have the best toque and emissions of any outboard. I have three boats and they all have e-tecs. No oil mixing, no smoke, start very easily and very quite. That 2006 you are talking about has an oil tank. let me know if I can help. [thumbsup]
 #246364  by hewesfisher
 Tue Feb 12, 2019 9:40 am
There's no "mixing" with modern 2-strokes. Haven't mixed a drop in mine since new and, FWIW, as of last May, there is only one engine manufacturer still making 2-stroke outboard engines and it's not Mercury.

Just like18ftTrophy said, no mixing, no smoke, starts within 3secs of turning the key. A 3-star CARB certified engine is a 3-Star CARB certified engine regardless of name on cowl and whether it is 2 or 4 stroke. [wink]
 #246405  by DavidA
 Fri Feb 15, 2019 4:20 pm
One thing I have not seen mentioned is the weight difference. 2-strokes weigh much less and that makes a huge difference for my little 12' fiberglass.
 #246409  by The Quadfather
 Fri Feb 15, 2019 6:45 pm
DavidA wrote:One thing I have not seen mentioned is the weight difference. 2-strokes weigh much less and that makes a huge difference for my little 12' fiberglass.


Good to know, Thanks!
 #246417  by Sideburns
 Sat Feb 16, 2019 10:37 am
My Love of two strokes stems from the dirt bike engines of my youth. All my outboards are old mix your own fuel two strokes. Put..put...put...pop!......put...put............put..............put. And the smell!...I guess those are all cons for the rest of you!
 #246418  by The Quadfather
 Sat Feb 16, 2019 10:50 am
Sideburns wrote:My Love of two strokes stems from the dirt bike engines of my youth. All my outboards are old mix your own fuel two strokes. Put..put...put...pop!......put...put............put..............put. And the smell!...I guess those are all cons for the rest of you!


The same reason I like my turntables, and tube amplifiers. :cheers:
 #246419  by TrackerPro16
 Sat Feb 16, 2019 11:29 am
I am 'generally' a 2 stroke preference guy with both outboards and motorcycles. BUT, I got my first 4 stroke (used) 7.5 hp outboard a couple years ago for trolling and my wife likes it because it is quieter and does not smell as bad if the wind is wrong. I like it as well, but I am not 'in love' with it. I have worked on a number of both over the years.
The saying that 4 strokes have one for power and one to wear out the engine comes to mind... [flapper]
As has been stated, the 2 strokes are lighter. It is more noticeable in the smaller engines than the bigger ones, say once you get over 100 hp, but in a small boat it makes a difference. Particularly if you are taking it on and off. I weigh all of my small outboards and you can figure around 10%-20% heavier for the same HP in a 4 stroke. The 7.5 I have is around 15 lbs heavier than the same HP in a 2 stroke. The older 2 strokes were lighter generally. And there were twins instead of singles, which are smoother. The weight is not as big a deal on my heavy 16', but on my light portable 12' it is a big deal. That extra weight is hanging past the end of the boat where I am also sitting.
There are more parts to wear out in a 4 stroke, and you have the changing of the oil and adjusting the valves. No hydraulic lifters on small outboards, not that you will be doing it very often. You also have to be careful how you lay them down or you will leak oil. 2 strokes tend to have a wider usable rpm band. 4 stroke RPM bands are narrower but they have a lot of torque.
A 2 stroke should not be any harder to start than a 4 stroke if both are in good running order. In my experience (after a number of gifted outboards and yard tools) the biggest issue is mix. If you are pre mixing fuel DON'T GUESS. Measure. It makes a big difference. When you change the mixture of oil and gas you are changing the air fuel ratio across the entire range. Ones with a tank that mix for you are great, but most of the smaller outboards do not have them. More oil leans out the air fuel mixture and can make them hard to start and they run like crap. Once you tune a 2 stroke for a mixture keep using that mix. MEASURE. :cheers:
 #246425  by G-Man
 Mon Feb 18, 2019 11:50 am
Chris, I have a 2006 115 HP E-tec which has over 1000 hours on it. They are solid motors and mine is set to run the XP100 oil. A gallon typically lasts between 75 and 100 hours, depending on how it's run. No oil/filter changes required, except for the lower unit. They run quiet, not quite as quiet as a 4 stroke, don't shake and don't smoke. The engines don't weigh a lot less than the high end 4 strokes, but as you know, every bit helps. A direct injection 2 stroke motor would not deter me from making a purchase on a boat, be it an Evinrude, Merc or Yami.
 #246426  by The Quadfather
 Mon Feb 18, 2019 12:02 pm
G-Man wrote:Chris, I have a 2006 115 HP E-tec which has over 1000 hours on it. They are solid motors and mine is set to run the XP100 oil. A gallon typically lasts between 75 and 100 hours, depending on how it's run. No oil/filter changes required, except for the lower unit. They run quiet, not quite as quiet as a 4 stroke, don't shake and don't smoke. The engines don't weigh a lot less than the high end 4 strokes, but as you know, every bit helps. A direct injection 2 stroke motor would not deter me from making a purchase on a boat, be it an Evinrude, Merc or Yami.


Words from the wise. Thanks!
 #246430  by hewesfisher
 Tue Feb 19, 2019 7:12 am
Everything G-Man says is true and they're also very fuel efficient. Have owned the DI Merc in my signature since new, not one problem, and just routine maintenance. I get 6.1mpg at 30mph turning only 3380rpm - awesome.

That said, this technology is outdated (for outboards anyway), and in Merc's case, now obsolete. DI 2-strokes will be around for many years, there are thousands upon thousands of them out there, and Evinrude is still producing DI 2-strokes. I suspect that, however, will change in the not too distant future.
 #246432  by TrackerPro16
 Tue Feb 19, 2019 8:34 am
Not Hewesfisher but I can answer that. Direct injection. Basically direct fuel injection into the combustion chamber but there are other fuel injection types that show great promise with less expense. The DI injectors are specialized and fairly expensive.
 #246436  by Sideburns
 Tue Feb 19, 2019 4:40 pm
Brings up a question..... How is the crankshaft and piston rod lubricated?
 #246437  by G-Man
 Tue Feb 19, 2019 8:01 pm
On the E-tecs , a pump provides oil directly to multiple points in the engine to keep it lubricated. A little bit of the oil is scavenged during the intake cycle, which also lubricates the cylinder/rings.
 #246445  by hewesfisher
 Thu Feb 21, 2019 7:18 am
G-Man wrote:On the E-tecs , a pump provides oil directly to multiple points in the engine to keep it lubricated. A little bit of the oil is scavenged during the intake cycle, which also lubricates the cylinder/rings.

Similar process used on the Optimax as well. Multi port oil pump lubricates crankcase and cylinders.