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Author Topic:   A few thoughts on 2 vs 4 stroke engines
Bigshot posted 03-03-2003 12:03 PM ET (US)   Profile for Bigshot   Send Email to Bigshot  
Most here know I am a big advocate of 4 stroke engines since my purchase of my 70hp Evinzuki a year and 130 hours of running time ago. The engine is fantastic, starts right up idles whisper quiet and burns little gas, downside is complexity to fix/maintain, cost and weight.

Well I recently purchased a 17' Neport with a 88hp Johnson 2 stroke on it and i can compare the 2 on basically identical hulls. The Johnson does require priming the bulb, choking the key, and advancing the throttle some to get her to fire when cold. She does it but I guess I am just spoiled with my 4 stroke with just turning the key(EFI). The 88 does smoke but not excessively and chugs along at idle speed without much complaint. The holeshot is quite impressive over the 4 stroke but top speed seems to be in the ballpark. I have not GPS'd it yet but I feel it is around 40-41mph vs 38-39 with the 4 stroke. At cruise at say 34-3800rpm she is relatively quiet, breaking the 4100rpm barrier she starts to growl and at WOT she is pretty loud but a "manly" loud that kinda gets the testosterone flowing. She does on the flip side burn considerably more gas, not quite sure how much, but a 6gal tank does not last too long. I will try and run some tests to further that study, if it does not sell too quickly.

Overall I am impressed with the Johnson and it runs like a sewing machine. The tradeoffs are slight and I still favor the 4 stroke but speed and power is not my concern as I run my boats easy and do not waterski, etc. I was having flashbacks while I was driving it yesterday and I remember that the V4 johnson on a 17' was always a great combo and still is. Problem was back in the 90's and earlier, we had no alternative. We either ran an OMC, Merc or Japanaese 2 stroke. Now with 4 strokes, DFI, 2 strokes, etc, I can see where we have as many debates on this forum as we do. Sometimes wish life was just a tad more simple. As far as the 2 vs 4 stroke debate, I still love 4 strokes but the 2 stroke does have advantages and I can give a more "honest" word of advice.

Tom W Clark posted 03-03-2003 12:12 PM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     

Good info. I see a couple things that ought to be mentioned (please correct me if I'm wrong on any).

The Newport weighs more than the Montauk. At least another 50 pounds because of its deck skin.

The Newport has bottom paint.

The Montauk has its Evinrude mounted on a set back bracket which accounts for its excellent top speed. The Newport does not have a set back bracket.

I'm sure we would all love to see hard numbers for both speed and fuel consumption. Itís an interesting comparision.

Bigshot posted 03-03-2003 01:27 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
True, I did not want to give hard facts because I don't have any at this point. They both have bottom paint. The newport weighs 50lbs more but my 70hp weighs 50lbs more. This engine is mounted in the blind holes which to the new owner would be a priority to adjust it up 2 holes if not put it on a manual jack plate. They are both running the same sized alum prop (14x17"). No doel-fins on either.

I was mainly impressed at how she ran at cruise, not as loud as it sounds at idle for some reason(wind in my face, etc). It has been a while since I drove a 2 stroke because all my friends now have 4 stroke outboards.

lhg posted 03-03-2003 02:32 PM ET (US)     Profile for lhg    
The real little dirty secret is that, except for fuel economy and start-up/idle smoke, the last generation (that's what they are, unfortunately) of 2 strokes, either carbureted or EFI, will outperform, both in reliability and performance, any of the cleaner DFI's or 4-strokes. This includes weight and cost too. The environmentalists have done a good sales job on the outboard engine buying public, making all of us think we're "bad guys" if we don't buy "clean", while the diesel transportation industry (including diesel boats/yachts) is out there polluting our atmosphere 1,000,000 times as fast. Until 2006, I'm not buying this line, and don't feel any obligation to be a field tester for OMC/Bombardier, Mercury, Yamaha, Honda or Suzuki. After 2006, unfortunately, I have no choice.

When I see the high price and inconvenience many boaters have paid for "new technology", supposedly better, but in reality not, I am not impressed.

For those that haven't seen Mercury's 2003 catalog, there are some very interesting and revealing figures presented on Optimax vs 4-stroke.

Using the Yamaha built Mercury 225 4-stroke against the 225 Optimax, on the same boat, they show the following:

Acceleration 0-20: Opti = 4.7 sec, 4-stroke = 6.3 sec

Acceleration 0-30: Opti = 8.3 sec, 4 stroke = 12.2 sec.

Top speed: Opti = 40.8 mph, 4-stroke = 38.7

Fuel economy on plane: Opti = 2.44mpg, 4-stroke 2.72mpg

So, except for some minor fuel savings, the 4-stroke offers inferior performance and power for it's higher weight, bulk and complexity. I doubt if reliability is any better than a conventional 225 EFI. Or look at this way, the extra fuel you're using is giving you better 2 stroke performance. So you're still not losing, simply getting the performance you are paying for. So why buy the heavier, costlier 4-stroke? Still makes no sense to me, except perhaps in the smaller engine sizes, or to impress your friends. Just don't try to keep up with them!

If they gave the figures for Mercury's EFI 225, there would be even more gap between performance, since the EFI will outperform the OPTI in all but fuel economy. Lighter and faster.

All of Mercury's own figures are still telling me to buy a low cost carb/EFI engine instead of all this new, lower performing stuff. So far the environmentalists seem to have taken us for a ride. Eventually, the performance aspect of the new technology will catch up, but I don't think that it yet has in 2003. So far, the only light on the horizon is Supercharging, since the conventional 4-strokes, now that the initial love affair is wearing off, are not cutting it performance wise on the larger engines.

where2 posted 03-03-2003 05:48 PM ET (US)     Profile for where2  Send Email to where2     
Mmmm, Superchargers... Reminds me of last night looking at a boat off E-bay that had a Johnson V-8 on the back, and a bottle of nitrous between the seats. Write up said it had been clocked at 118mph. At first, I thought: Behind what pickup truck? then I noticed the V-8 and the nitrous. Interesting concept for lack luster hole shot...

Then in the parking lot is my little 1.8L VW with a supercharger, running an 8 valve head, and one cam shaft. 158hp stock, close to 200hp if you spin the charger faster and add a chip to the computer. This is all before variable valve timing, and new jazzy stuff.

Why not adapt that supercharger concept to an outboard.... just find an efficient charger design.

captbone posted 03-03-2003 07:33 PM ET (US)     Profile for captbone  Send Email to captbone     
Land and Sea, a company in the northeast used to make a turbo charger (or something like it) for two stroke outboard motors. You could get a 200 merc (1980s) to put out more than 350hp. The thing was a literally a BOMB. You could not run with a hood on because it was so big. Too much power. Merc is coming out with their supercharged 2.6 liter four stroke. But I am going to stay away from that for a while. There is just no replacement for CC's and liters. You can get a GEO Metro to put out as much power as GTO but which one has the power. Just my two cents.
boxers posted 03-03-2003 10:08 PM ET (US)     Profile for boxers  Send Email to boxers     
Just swapped out a 200 Yamaha salt H20 series for a F225 Yamaha on our OR-20.

WOT (4 stroke)225=42 at one hour
WOT (2 stroke)200=46 at 200 hours

The new engine is not broken in just yet so it was just a very quick comparison with the GPS. This seems to be the trend that the performance isn't is good from the 4 stroke motors as the horsepower ratings would suggest.

An aside, for motorcycles 2 strokes break in very fast 2 hours and you have full power. 4 strokes take 10-20 hours to reach full power under similar conditions. Maybe in time the F225 Outboard will loosen up and produce more power?

Great topic

Peter posted 03-04-2003 08:37 PM ET (US)     Profile for Peter  Send Email to Peter     
With the 10 percent allowable slop in the HP ratings, it is possible that Boxers' old 200 SWS put out more HP than the new F225 does. All the data I have seen on the F225 suggests that Yamaha has been very liberal in rating the power output of the F225, taking full advantage of the 10 percent allowance. See a comparison of the 225 SWS with the F225 at where the data shows the F225 is almost 5 mph slower than its 2-stroke cousin.

It seems to me that if the F225 actually produced the same WOT HP output as its discontinued 225 2-stroke EFI cousin, the data might show that the F225 actually burns more fuel to achieve the same output. Spinning the valve train doesn't happen for free.

lhg posted 03-05-2003 03:01 PM ET (US)     Profile for lhg    
Yamaha seems to have a habit of stretching HP ratings. Their 70's and 90's come to mind, as does the 100 4-stroke, which Mercury marketed as 90. Now Yamaha has dropped it to 90 also. The 150HP V-6 2-stroke is no match for either a Johnson or Merc 60 degree 150.

It seems they would have been better off labeling this new F225 as an F200. Since they do make it in 200HP version, would one be better off saving the bucks and buying the F200?

Peter posted 03-05-2003 05:40 PM ET (US)     Profile for Peter  Send Email to Peter     
It's no secret that if you want to go fast, you get a Mercury, if you want to get home, you get a Yamaha. ;)
jimp posted 03-05-2003 06:24 PM ET (US)     Profile for jimp  Send Email to jimp     
Bigshot & lhg -

You're not helping at all! What's the answer? I need a new 225 for my 1990 Revenge W/T.

Suzuki EFI 225, with 6 year warranty = $13,000 (local dealer)

Yamaha 2-stroke 225 with 1 year commercial warranty = $13,800 in Canada (the $13,000 is US $).

Yamaha F225 with 1 year warranty and aluminum prop = $15,000 (local dealer).

Yamaha F225 with 1 year warranty from Canada = don't know yet.

I put about 20-25 hours on the 225 per year (about 60-75 on my kicker trolling).

So do I buy newer technology that gets better mpg and costs $3,000 more? Or buy the cheaper EFI that will get worse mpg but will take up to 15 years to make up the additional $3,000 that the 4-stroke would cost in gas money?

I have 8 days to make up my mind.

Thanks, you guys are great and know so much more about this than I do!


lhg posted 03-05-2003 07:07 PM ET (US)     Profile for lhg    
JimP - All joking about Mercury/Yamaha aside, and not being familiar with the engine Dealerships up there in Alaska, I would recommend a conventional 2-stroke, EFI if possible. I still think one of the best 225's out there, for the money, is the Merc EFI, like Louie Kokinis uses, but evidently that's not an option for you. I have absolutely no knowledge about the Suzuki 225.
I wasn't aware Yamaha was even making a conventional 225 this year.

I recently saw a new 22 Guardian with a black Mercury/Yamaha 225 4-stroke on it. It looked absolutely huge, and out of proportion to the boat, I think. That engine would be MY last choice. I guess it all gets down to whether you object to a little oil smoke.

Peter posted 03-05-2003 09:02 PM ET (US)     Profile for Peter  Send Email to Peter     

In a simple 2-stroke v. 2-stroke comparison, I'd take the Yamaha Ox66 over the Suzuki because the Yamaha displaces 3.1 liters and the Suzuki only 2.7. I'm a big believer that more displacement is a good thing. The Yamaha delivers an honest 225 HP and to get that same output out of the smaller Suzuki it must have to work harder. I admittedly have no experience with Suzuki but I have had the Yamaha for three seasons now with no trouble. Optimal performance requires that you keep the O2 sensor clean. Use of the "Ringfree" fuel additive seems to help keep it clean.

Of course nothing is ever that simple. In your case, I think Suzuki might be the better choice. The ease of acquisition, the longer warranty and the reputable local dealer tips the balance towards Suzuki.

If you have 100 lbs of kicker and kicker bracket then an F225 might put too much weight on the transom. Also, with your usage, you may never be able to recoup the extra cost in expected fuel savings, assuming the F225 is more fuel efficient than the Ox66 (I have my doubts based on Pursuit's test data, see the link I posted in this thread). While I may not always agree with LHG on which is the better engine brand, I am also of the opinion that the F225 would be my last choice. It truly is a large beast and makes the large Ox66 225/250 look small when they are side by side.

The cheaper 2-stroke EFI seems to make the most sense to me unless you are really concerned about smoke and sound level at idle.

Bigshot posted 03-06-2003 09:54 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Hell with 20 hours a season, just use the kicker and save yourself some money :)

I would do the Zuki and use the local dealer. If you do decide to get the 4 stroke, you won't need the kicker but if you keep the kicker(for safety), weight will be REAL high on that transom. Get the Zuki. What is wrong with your engine?

jimp posted 03-06-2003 10:53 AM ET (US)     Profile for jimp  Send Email to jimp     
lhg, Peter, BS -

Thanks for the input. Peter, I read your comments in other threads about the 2-stroke, 4-stroke on the Pursuit, good stuff.

BS - My 1990 225 blew last summer, 321 hrs, destroyed lower main bearing, hole in the block by the number 6 piston, two destroyed pistons, cracked crankshaft. Repair estimate is $8,200.

Tom W. Clark asked some good questions in the General Forum about my Dead 225. I think its time I find the answers to them.

You guys gave me the info I need. If I go new, I'll get the Suzuki. Rebuild/used is tough. Shipping to Alaska, warranty?, "getting taken" are concerns.


gss036 posted 03-06-2003 05:13 PM ET (US)     Profile for gss036  Send Email to gss036     
If you are close to the Canadian border, check the dealers out and see what you can save on the exchange. I know of several people here in our area go across the border and buy. Some will use a broker, others just have the dealer write export on the bill and they don't pay the GST & sales tax(otherwise about 24%)I bought a John Deere tractor and did not have any problems on duty, customs guy looked at the bill and waved me on through the border. I think warranty is a major concern for you and maintance. The lower end needs annual oil change and head gaskets need changed at least every other year, especially if you unable to flush as the salt really does a number on gaskets. I had a friend who got 10+ years on a Suzuki, blew it up by running WOT too long and it seized up on him, then bought another one.
SaintGeorge posted 03-06-2003 06:50 PM ET (US)     Profile for SaintGeorge  Send Email to SaintGeorge     
Rant about 4 stroke and 2 stroke.

One of the major advantages of outboard, even big outboard power was always simplicity. And reduced weight. Lastly, some pure performance. There was a moderate premium in propulsion cost v. I/O or inboard, but not extreme.

With these new 4 strokes (and the very complicated but well running EFI, both crankcase fueled and direct injected) most of the simplicity is long gone. There are computers, multiple injectors, high-pressure fuel pumps, fuel return lines, Engine Control Units (computers) knock-sensors, temperature sensors, so on and so on.

Yep, the days of the Mercury Thunderbolt 40 the most balanced combination of simplicity and power ever in an outboard) four- having a single suction-type fuel pump, two Tillotson carbs and a self-contained magneto ignition are long, long gone.

With the costs of the leading edge equipment, the premium of big outboard power over inboard power is far from moderate.

So, other than re-powering existing craft, and perhaps specialized fishing boats (low freeboard small racing, errr bass fishing boats) for the life of me, I cannot understand why any naval architect would design a pleasure craft to be powered by a big, heavy, 4-cycle v6 outboard. If the craft is up there in the 22 to 30 foot range, it would seem to me to make a lot more sense to use a good, big-block injected V8 of like 300 hp with a dual prop outdrive. If you want good room in the back for fishing, you locate the engine under the console, and run a drive shaft back to the outdrive. The powerplant, all installed in the boat, would be less than HALF the cost of one of those big 4 cycle outboards. And if you used TWIN 4 stroke V6, woo-hoo!! A great show-off, what with $35,000!!! of engine hung off the back, but still, a 300 hp single I/O would still come close in performance, and of course for very little cash (just the $10,000 range total powerplant outlay) you could move the I/O up to a 8 to 9 liter V8 and 350 or 400 hp. I know, not so head-turning. But... are the outboards really worth $25,000 in performance value over the inboard power? You already know my answer.

As far as the "little" motors go. For the 20 foot and smaller Whalers? It is a shame that all this pollution stuff had to make things so expensive.

Last I knew the typical outboard boat was operated less than 40 hours a year. Many less than 20 hours of operation. It is hard to believe that enough fuel is put through an engine to justify all of the huge effort and expense going on to meet these regs. Frankly all it did was open the door for off-shore engine builders to take business away from domestics, our fellow citizens, reducing U.S. jobs and economy.

Once the improvements were made to keep the oil out of the water, which I am all for and is much cheaper to do than all the other pollution control engineering work, I think things would be in good shape. Again, 20 to 40 hours of operation just does not seem worth the effort.

I would venture to say that in California, as well as the rest of the country, pollution from weed-whackers, chain-saws, lawn-mowers, four-wheelers, farm tractors, and even snow-mobiles is of a scale that makes all of the polution from outboards, even the 2-stroke-carb type, unmeasurable. That's just an opinion, maybe there are facts published?

I think the outboard motor was just "an easy target". It is making a lot of people "feel good" that they are doing something about those filthy outboards. I know there were some issues on Tahoe, and even on Winnipesaukee (NH) they have issues because MBTE shows up in the lake... which is also the drinking water source for the area, and is blamed (without proof) on the boats. But is this re-engineering really going to solve the special local problems?

Get ready for the official reports and studies that will say how much healthier we all are because of the wonderful regulations. Just before somebody elses recreational toy is attacked so that folks can again "feel good that they are doing something about pollution".

Oh, by the way, I DO like a lot of the 4-cycle motor performance. Our family boat once had a Homelite 55 Grand-Prix 4-cycle engine. Really nice running machine, too. But as for the new, big 4 strokes, they have a lot to like too. Especially the low noise aspect. However, I do not like the costs. You know, there is an awful big premium to pay so that those 20 to 40 hours a year of running time are "quieter".


jimp posted 03-07-2003 11:00 AM ET (US)     Profile for jimp  Send Email to jimp     
lhg -

I found a 2003 Merc 225 EFI in town for $12,100 including tax and installation, aluminum prop. Could you send me an email with more info on Merc EFIs?



Bigshot posted 03-07-2003 11:50 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Buy it Jim!

St George( I am Greek by the way)where the heck are you gonna get a 9 litre engine? I agrre with most of what you say, just criticizing your "novel" :) Have a nice weekend ya'll going to bike week.

cvye posted 03-07-2003 01:05 PM ET (US)     Profile for cvye  Send Email to cvye     
What about a motor used primarily for trolling? My Montauk ain't gonna get anywhere near WOT around Pt. Judith, RI on a Summer's day...
The 4-stroke propaganda says that they don't "load-up" during trolling, implying that the 2-strokes that still true with the new-fangled 2-strokes like the Evinrude e-tec?
lhg posted 03-07-2003 02:19 PM ET (US)     Profile for lhg    
JimP - I would have to agree with Nick on the Merc Saltwater 225 EFI. Sometimes Nick amazes me! They are a great motor, and since only Merc and Suzuki are even making one now, the Merc is by far a better engine, with 3.0 liters instead of 2.7, and outsells the Suzuki probably 100 to 1. Saltwater corrosion resistance could be better also. I think it really puts out about 240HP or even more, since it's really a detuned 250. After running that old carbed OMC, you'll think you died and went to heaven. I have recently seen two brand new US Customs boats, each with four Merc 225 EFI's on them, so they must think they're pretty good also.
You will love the sound of that engine, or like Mercury used to advertize about the engine, a "wolf among sheep".

I would correspond with Louie Kokinis, since he has been running one of these on his 22 for several years now, and really likes it, I believe.

I would not waste money on an aluminum prop for an engine like that. For your configuration, you will want either the 4 blade "Offshore" or 3 blade "Mirage". They can be had for about $400. I think Louie likes the Offshore, and can help you with pitch. You should get 50 mph out this engine, at least, depending on hull bottom condition. I think Louie says he gets 54.

Now the good news. Mercury just announced a full, complete, non-declining three year factory warranty on new 150-250 EFI's, plus a rebate. So be sure your dealer gets you that added benefit also. There may info on the promotion on their website. I think you have to buy before April 15th.

Good luck to you, and if you get it, let us all know how you like it.

jimp posted 03-07-2003 07:49 PM ET (US)     Profile for jimp  Send Email to jimp     
lhg & BS -

I'll brief my wife tonight! Daughter's graduation present!


jimh posted 07-11-2005 08:10 AM ET (US)     Profile for jimh  Send Email to jimh     
[Thread closed]

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