Classic repower question: 2 or 4 stroke???

[3charter]

Was searching around the forum and didn't really see anything about this. I know many will be staunch 2 or 4 stroke supporters, but if comes time to re-power an 18-20 foot bay boat(center console)...what would be your choice??

Dependability is an issue, of course. I know the hole shot would be different with a 4 stroke, as well as higher engine weight. All things considered, what is your choice and why? Real world knowledge of the specific plant would be great, as well as a brand recommendation.

Really interested in your take...Thanks!

 

[JimS123]

Re: Classic repower question: 2 or 4 stroke???

I've owned nothing but 2-strokes since forever. My first was a 1955 Merc.

I had always been impressed with the 4-strokes because of their smoothness and quietness, even though they lack the pleasant aroma of oil burning.

That was until I got the urge to buy a new motor and found out about what I would consider excessive maintanance - adjusting valves and other things that the average guy would have to go to a dealer for because of special tools, etc.

On the smaller motors, weight is also a major factor. I ended up buying a 25 HP 2-stroke becase it was substantially lghter and required much less maintenance. I replaced a 37 year old 2-stroke that had served me well. My son still uses it.

The weight difference is not as pronounced on the larger engines, but I think I would still opt for a 2-stroke as long as it was still legal where I boat.

I have first hand experience being on a boat with an E-Tec and that would be my choice. They do run nice. However, I have seen many recent Merc 2-strokes and they aren't too shabby either. I would not hesitate to buy a Merc, but only if there was no BRP dealer in my area.

 

[Bob_VT]

Re: Classic repower question: 2 or 4 stroke???

Welcome to iboats!

The key is support. What dealer's are in your area that you have confidence in.

My personal choice 2 stroke

 

[jevery]

Re: Classic repower question: 2 or 4 stroke???

The new VF series from Yamaha matches or surpasses the 2-strokes in performance, including holeshot. Weight is about the same as the DI 2-strokes and fuel efficiency looks to be a little better in the direct comparisons I've seen. The additional maintenance cost of a 4-stroke is effectively offset by the cost of 2-stroke oil, especially for the larger engines.

http://www.yamaha-motor.com/assets/...nst_2200tournamentbay_vf225la_3-24-10_bay.pdf

IMO it's a matter of personal preference of engine characteristics as opposed to a clear advantage in any area of performance or cost. That and proximity of dealer support.

 

[wellsc1]

Re: Classic repower question: 2 or 4 stroke???

Welcome to iboats!

The key is support. What dealer's are in your area that you have confidence in.

My personal choice 2 stroke

Bob_VT,

Put perfectly! The confidence in my motor mechanic prompts me to stay with Yamaha or Mercury - the two he works on. I will rely on his recommendation for a 2 or 4 stroke at whatever hp I'm looking at.

 

[tashasdaddy]

Re: Classic repower question: 2 or 4 stroke???

etec or yammy 4 stroke would be my choice.

 

[dingbat]

Re: Classic repower question: 2 or 4 stroke???

That was until I got the urge to buy a new motor and found out about what I would consider excessive maintanance - adjusting valves and other things that the average guy would have to go to a dealer for because of special tools, etc.

The valves on a 4 stroke need checked at 100 hours and the timing belt changed at 1000 hours. Unless your average guys tool kit includes a diagnostic laptop and OEM proprietary software, don't plan on working on a DFI 2 stroke either.

Looking to repower with 225 or 250HP outboard in the next year. Have pretty much narrowed the field down to Yammie or Merc. I like the E-Tec but can't see paying a premium with nothing in return.

 

[ChrisAG]

Re: Classic repower question: 2 or 4 stroke???

The valves on a 4 stroke need checked at 100 hours and the timing belt changed at 1000 hours. Unless your average guys tool kit includes a diagnostic laptop and OEM proprietary software, don't plan on working on a DFI 2 stroke either.

You'll take the 2-stroke into the dealer only if something goes wrong. Most people can perform routine maintenance on an Optimax or E-tec (change spark plugs, gear oil, even impeller). The same cannot be said of a 4-stroke - routine maintenance is more difficult and so most people will NEED to take it into a dealer for 4-stroke mainenance (above & beyond the items stated). So the extra cost of 2-stroke oil is more than offset by the cost and trouble of hauling the boat in to the dealer.

Looking to repower with 225 or 250HP outboard in the next year. Have pretty much narrowed the field down to Yammie or Merc. I like the E-Tec but can't see paying a premium with nothing in return.

I wouldn't say "nothing in return;" with even fewer moving parts than an Optimax they're probably the world's simplest modern outboard, despite the computerized this'n'that (which all outboards have nowadays). Fewer moving parts generally means increased reliability.

 

[dingbat]

Re: Classic repower question: 2 or 4 stroke???

You'll take the 2-stroke into the dealer only if something goes wrong. Most people can perform routine maintenance on an Optimax or E-tec (change spark plugs, gear oil, even impeller). The same cannot be said of a 4-stroke - routine maintenance is more difficult and so most people will NEED to take it into a dealer for 4-stroke mainenance (above & beyond the items stated). So the extra cost of 2-stroke oil is more than offset by the cost and trouble of hauling the boat in to the dealer.

What routine maintenance does a 4 stroke required that is so complicated? Sticking an oil vacuum down a tube every 100 hours to drain the oil?

Don't even get me started in the oil argument. I buy oil in 55 gallon drums. You can do a lot of maintenance for the price of a drum of DFI oil.

I wouldn't say "nothing in return;" with even fewer moving parts than an Optimax they're probably the world's simplest modern outboard, despite the computerized this'n'that (which all outboards have nowadays). Fewer moving parts generally means increased reliability.

So, I'm going to spend $3K more upfront in hopes that it breaks down less?

I know far too many guys running large HP 4 strokes that have 1000's of trouble free hours on them to even consider buying into this claim. My boat builder is so confident in 4 strokes that they stopped offering 2 strokes 10 years ago and have never looked back.

 

[ChrisAG]

Re: Classic repower question: 2 or 4 stroke???

Guess we'll just have to disagree. I love my DOHC 2.5L Mazda V6, but in my opinion it belongs just where it is - in a car, not hanging off the back of a boat. I believe the reason large 4-strokes became the norm was out of perceived necessity; emissions regulations were coming into play and some manufacturers went the 4-stroke route as the answer, rather than develop their own versions of DI 2-strokes. Yes 4-strokes have been refined and improved performance wise (as have DI 2-strokes), but they were always a weight and complexity compromise (not to mention holeshot performance). Maybe for the most part those deficiencies have been addressed in the current 4-strokes. But then again, E-tecs have been undergoing constant improvement as well.

I've been using a 12 year old V4 FICHT - love the starting, throttle response, and fuel economy (and the oil economy) - and it doesn't block my view aft like some engines would (I have a thing for compact engines I guess).

I don't believe E-tecs are the most expensive engines out there (though not the cheapest, I know).

 

[tashasdaddy]

Re: Classic repower question: 2 or 4 stroke???

3charter, buy what you want, or you will never be happy with it. opinions are just that person thoughts and education on any subject. everyone has one.

the best advice is buy one that you do not have to travel 50 to 100 miles to get proper dealer service.

 

[clarkbre]

Re: Classic repower question: 2 or 4 stroke???

So I have a dumb quesiton that I need clarification on. When you say "DI" in regards to a 2 stroke, what do you mean?

Is that a direct oil injection or a direct fuel injection or something?

 

[ChrisAG]

Re: Classic repower question: 2 or 4 stroke???

So I have a dumb quesiton that I need clarification on. When you say "DI" in regards to a 2 stroke, what do you mean?

Is that a direct oil injection or a direct fuel injection or something?

Direct Injection is in regards to fuel, and specifically means it is directly injected into the cylinder, as opposed to traditional fuel injection that injects the fuel into the throttle body (mixing it with air before it enters the combustion chamber).

Computer controlled Direct Injection is part of what makes the increased fuel economy and reduced emissions possible. Fuel is only injected when the ports are closing (or are closed completely) so no fuel is wasted. Further, since the piston tops have a small dish in them, at low speeds very little fuel can be used without the danger of a too-lean condition.

As for oil injection, all modern two-strokes have had that for some time now. I don't think you can buy a two-stroke that requires you to mix oil with gasoline.

 

[JimS123]

Re: Classic repower question: 2 or 4 stroke???

What routine maintenance does a 4 stroke required that is so complicated? Sticking an oil vacuum down a tube every 100 hours to drain the oil?

.

As was mentioned above, readjusting valves and changing timing belts. The computer controls cannot be diagnosed without having the proprietary software.