Thoughts on 2-stroke vs. 4-Stroke?

[onthelaketwo]

my 2 stroke starts on first key turn

No choke, and starts on first key turn even if I forget to squeeze the bulb.

mine is quiet but I never measured with db meter I guess that would be the test

[ROLAND]

Never owned a 2 stroke but I have ridden in a lot of boats rigged with them.... Don't care for the "smoke" and I think they're louder than a 4 stroke. I have a 4 stroke Yamaha 75 and I love not having to prime it... just turn the key and go.... about the only real drawback I've found with 4 strokes is the size and weight.... my 75 weighs 369 llbs...

[RJF]

Nothing wrong with the new 2-strokes. Opti from Merc is not bad. E-Tech from Evinrude is better, in my opinion. Quiet and powerful. I do not have a trailer, so I must do oil changes while on the lift. I'm always concerned about a spill. I live on a small canal, which would be bad, if I dropped 5 quarts of 10-W30 in it. I just sold a pontoon with a Merc 4-stroke. My new boat has a Honda 4-Stroke. I use an extractor to make the old changes safer, but a clean burning e-tech weighs less, and probably would outperform the 4-stroke crowd. I believe the Evinrude actually has more stars in the pollution ratings than most all 4-strokes.

Not sure I can say one is better than the other. There are a lot of really good outboards out there.

[Mosnowman]

Love my Mercury Verado 150....

By the way your boat's name is absoluetly priceless! love it!

[Mr Geets]

going from an inboard v6 in my previous boat and loving tthe engine I was pretty apprehensive about the outboard Merc 90 efi 4 stroke that came with my pontoon. I am absolutely sold with fuel economy, quiet and the ability to idle right down for trolling. Starts instantly. Just nothing bad to say.

[pote]

Couple of things I've learned in the last year's class of the school of hard knocks - EFI 4 strokes dont need a primer bulb because the fuel supply module (FSM) has a low pressure pump to pull fuel from the tank into the FSM and then a high pressure pump to feed the injectors. In almost ever modern (2000 and later) fixed mount fuel tank, there is an anti-siphon valve (ASV) on the outside of the fuel pickup and you dont need a bulb until the FSM fails. But it's handy as heck when your low pressure pump wont come on.

If your shop tries to put a new bulb on your line, deny them the profit. Mine replaced my fuel line with a new bulb for no reason and says they do it automatically because so many bulbs have problems. It's total BS and I told him it was an unauthorized repair.

An ASV costs about 8 bucks and is easy to put in your supply line if you want one. You can even thread it onto your Racor filter. Id rather have a racor than a bulb!

[Bamaman]

My observations on my owning two pontoons with a 2 stroke and a 4 stroke:
. Pontooners most often prefer 4 strokes because they're running @ relatively slow speeds.
. Modern 4 strokes are long lasting, quiet running and "green." Resale value is superior.
. Modern 2 strokes pull tubers/skiers better, and have a 3-4 mph faster top end. Their factory rated horsepower is very often conservative.
. 4 strokes and 2 strokes both get loud at full throttle, and they get about the same mpg.
. A 4 stroke oil change per year offsets the costs of using high quality outboard motor oil in a 2 stroke. Maintenance is not an issue with a 4 stroke for a few years.
. All major brands of motors are very good. Yamaha's pull better resale prices, however.

If you're going to be running 5000-6000 rpms all the time, get a 2 stroke. If you're going to be running in the 4000's or less, get a 4 stroke.

[GregF]

If you're going to be running 5000-6000 rpms all the time, get a 2 stroke. If you're going to be running in the 4000's or less, get a 4 stroke.

Excellent advice

[belercous]

3 boat mechanics have told me to stay with a 2 stroke. Fewer moving parts (less to go wrong) & faster power on demand. The mechanics say they have less trouble with 2 strokes & they're easier & cheaper to fix.

I'd kind of prefer a 4 stroke for the lower fuel burn though.

[GregF]

Engine technology, particularly 4 stroke engines has evolved to the point that if you have a "block" failure, it was a manufacturing defect.

Your typical car engine is still going, long after the body rusts to oblivion and all the other parts have gone bad ... with far less maintenance than most people do on their boat.

Any 2 stroke that is still legal to sell here will have as complex a computer setup and as many electrical parts to go bad as a 4 stroke.

Mechanics are just afraid of the unknown. You notice Ed who is a long time certified car mechanic, is an I/O fan, because that is an engine he knows inside and out. I think that once we lure him over to the dark side and he gets comfortable with outboards he will never go back.
It reminds me of guys who refused to work on "foreign cars" back in the olden days. Generaly, once they got used to them, they criticized the "junk" American companies were building. Then around 1980 or so, the US started building the 200,000 mile engine using similar processes as the Japanese were using.

[MrGadget]

I think some things are at least a little absent from this discussion. Comparing latest 4-stroke to older 2-strokes isn't fair. Latest to Latest is the only fair comparison. The current run of 2-strokes using oil injection from a reservoir can be very economical to run in terms of fuel burn and the utter lack of required maintenance. I want a boat that doesn't add to my honey-do list. 4-strokes require annual maintenance, 2-strokes don't. That means no trips to the shop, no lost water time. Whether you do the maint. yourself, or take it through the shop, that's time and money. As far as oil consumption, stop buying retail oil. Once you have a couple retail jugs, take them to a cooperative shop and have them refill them from their bulk stock...much cheaper, and takes only a few minutes, and depending on your usage, may last the season. Also don't compare oil consumption of a brand new 2-stroke. During break-in, the consumption is high. If you're beyond that period, and still think you're burning a lot of oil, have your shop hook up their laptop and reset the motor out of break-in mode. If you do use the boat a lot, perhaps get a bigger reservoir.

Boat weight is a factor also. If your boat is light and smaller and designed for speed planing, a 4-stroke may be a better fit. If you're bigger and heavier, the lighter weight and the higher torque of the 2-stroke would be necessary. The higher torque gets skiers and such up easier too, so factor in whether you do a lot of pulling, or if you're typically full of people/load versus just two of you and minimal gear.

My 250 Etec doesn't smoke when it starts and is very quiet. No bulb squeezing unless it has sat for weeks. If I go out back-to-back weekends it starts fine without a squeeze. Wind noise is as much a factor in terms of "conversational comfort" as the motor. Flat out, they all are loud. My experience, is the low rumble at cruise (15mph) is barely audible over the water against the hull.

My last thing is up-front cost: When I built my boat, the Etec was quite a bit cheaper than the comparable 250 Honda.

[GregF]

The ONLY maintenance difference would be an oil change every 100 hours. You don't need to take the boat anywhere to do that. I suck it out right on the lift, screw on a new filter and pour in 2.5 quarts of oil.

I am sure you use more than 3 quarts of oil in 100 hours.

For the purposes of complexity, the ECU on that Etec is as baffling to an old school shade tree mechanic as the one in my 4 stroke.

[ronb]

pour in 2.5 quarts of oil.

I am sure you use more than 3 quarts of oil in 100 hours.

My Optimax (2 stroke) uses about 1qt of 2 cycle mix for every 7 gallons of gas and I burn about 7-8gallons of gas every weekend. I think my motor may have a drinking problem...
-ron

[badmoonrising]

Mechanics are just afraid of the unknown. You notice Ed who is a long time certified car mechanic, is an I/O fan, because that is an engine he knows inside and out. I think that once we lure him over to the dark side and he gets comfortable with outboards he will never go back.
It reminds me of guys who refused to work on "foreign cars" back in the olden days. Generaly, once they got used to them, they criticized the "junk" American companies were building. Then around 1980 or so, the US started building the 200,000 mile engine using similar processes as the Japanese were using.

Nothing is "unknown" to me Greg. I prefer I/Os because they are easier to maintain without having to go to a dealer for damn near everything (i.e. proprietary software that's becoming more common in both marine and automotive engines). As I get older and lazier, and (IF) the I/O on my Party Cruiser gives up the ghost, I'd consider an outboard. I was one of those mechanics that had the audacity to keep going back for training on whatever newer system came out. I was a mechanic during the "end of the carburetor" years up until I quit the field and started working for the Postal Service because the automotive field stopped being stable career in the mid 90s. I've since held onto my certifications, and kept my knowledge up to date. Vehicles these days (I've always said it) get better and more reliable every year. The marine industry is finally keeping up with technology. I also have several years of diesel training. If Mercruiser had the diesel option in 2006, I would have a diesel in my PC now. These days, injected I/Os are ever bit as complex as injected inboard engines, I've stated more the once my disdain for carbs and my comfort level with injection. In fact, I'm considering adding an aftermarket TBI injection to my 3.0.

I have NEVER been "uncomfortable" with outboards. In fact, out of the 8 boats I've owned, 6 were outboards.

I prefer I/Os on pontoons due to the increase in deck space, quietness,tried and proven longevity (with proper maintenance), simplicity, etc. The only weak point of I/Os is cramped maintenance and the winterization requirement, both of which Mercruiser made easier in the last few years with quick drain systems. Not to mention the fact that a comparable I/O is several thousand cheaper to buy. If I remember correctly the I/O vs outboard PC was a $3500-$4000 price difference.

[bassn386]

I have never primed my 200 hp Optimax (2006) on my bass boat.
Have had the Yamaha 4-stroke for two seasons now and love it. Friends who have 2 strokes get on and while I'm backing away from their dock will ask if the motor is running. We took a 50+ mile round trip earlier this week and even at 4000 rpm, I could talk fairly normally to the two guys sitting across from me.
Incidentally, I just checked the oil around Labor day and it hasn't used a drop since the 20 hour change. It now has about 95 hours on it.