Two Stroke or Four Stroke

[MetroWalleye]

Well, I just blew a cylinder bearing on my Optimax 135 this past week and basically the motor is a complete loss. I guess I'm in the market for a new motor.

I have a 18' Lund Pro V and am thinking about moving to a four stroke, possibly a Yamaha 115.

Any suggestions or opinions?

I know that I'll never go back to the Optimax motors, I've had problems with that thing since day 1.

[MuskieJunkie]

I would go 4 stroke all the way, with these gas prices I think 2 strokes, especially carburated are on there way out, you can already see the resale dropping on used ones.

[snoozebutton]

I agree MuskieJunkie. There's valid arguments for and against each motor but now with the high gas prices it tips the balance in favor of the 4's.

[Sandmannd]

I agree, would go with the 4 if you have the money. Better on gas and very quiet.

[Down Deep]

I had a 1800 Pro V and that is a big beast of a boat to push with a 115 anything. I'd look at getting least a 135, but I think a 150 would be a better choice.

[blarkey]

I have a 115 Yamaha on a 1750 fishhawk and I love the motor and I would buy nothing else ,the gas millage alone will blow your mind.

[Jason Durham]

The fourstrokes are nice, quiet and fuel efficient. However, I don't think I'd deviate from the Opti. In the 115 hp range, the Optimax will actually get better fuel economy than a Yamaha F115 and Honda 115 fourstroke.

I've been fortunate in that I've gotten to drive a lot of different outboards and have to say all brands have made some major improvements and innovations throughout time. I've been extremely impressed with the Optimax and have owned 3 of them. I've never had an issue with any of the 3.

[Musky_Madness]

I will second Jason on the Opti...an amazing motor! The fuel mileage is excellent. It sips fuel compared to the traditional 2 strokes. I would argue it's almost as clean as the fourstrokes as well with very little smoke/smell.

[MuskieJunkie]

I have a 115 Yamaha on a 1750 fishhawk and I love the motor and I would buy nothing else ,the gas millage alone will blow your mind.

What do you get for mileage?

I run a 90 HP Merc 2 stroke carb, on a 16.5' Smokercraft, 4.5 mpg. UGLY! I would assume 4 strokes and optis are about twice that.

[PerchJerker]

For a boat/motor the size you're talking, I'm a fan of DFI motors like the Opti over 4-strokes ---- unless the noise is a big issue for you, then a 4-stroke would get my vote.

DFI motors should give you a little better performance and just as good of fuel efficiency as a 4-stroke ..... although the differences are slight, as both motors have improved and are a lot closer in performance and fuel efficiency than they used to be.

Too bad you've had so many problems with your Opti, that 135 - 150 - 175 Opti has an excellent (and well deserved) reputation.

[jerkin'm]

Don't listen to what PerchJerker is saying..He was drooling over my Yami f150 on Sunday.. The f150 is super quiet (I have tried to start it while it's already running) fuel efficient and plenty of power for my glass boat. I wouldn't go smaller than a 150 on that boat if you go 4 stroke...By the way PerchJerker I could have used a net man later on Sunday on tonka..

[marine_man]

I had a 1800 Pro V and that is a big beast of a boat to push with a 115 anything. I'd look at getting least a 135, but I think a 150 would be a better choice.

I agree with this setiment as well. Using the 75% of max motor spec you should be above a 130 hp motor to have "decent" performance.

I'm a big fan of DFI engines as well, mostly from the performance standpoint.

marine_man

[MetroWalleye]

Any opinions on the Mercury 115 EFI 4 stroke?

[PerchJerker]

Don't listen to what PerchJerker is saying..He was drooling over my Yami f150 on Sunday..

Actually, I've got my tournament partner's Skeeter 1880 hooked up to my truck right now ....... and I'm drooling over the Yam 200 HPDI hanging off the back of it. I predict that a quick cruise down the lake at 55 mph will take care of the drool

metrowalleye - I think you'll see a big fall-off in holeshot, power, speed, etc. going from a 135 Opti to a 115 4-stroke. In my opinion a 115 is too small for your boat.

[MetroWalleye]

[jerkin'm]

My brother in law has an 18' ProV with a 140 Johnson 4 stroke. The thing is a complete dog loaded with gear. Put a full tank of gas in and fill the livewells forget it...It's not just about all out speed in my opinion. Getting on plane in a hurry can be important too..My Skeeter is rated for a 200 and I put a 150 4 stroke on it. I would have only gained around 4-5 mph with the 200 hpdi...Then I would have been forced to get a T8 if I wanted to troll...The way it is, I lose a little top end but can still troll with the big motor on the occasions I want to and didn't have to spend the extra $$$ for a kicker. Are those tests you quote with a loaded up boat or empty?

[MetroWalleye]

jerkin'm-

Is his Johnson 140hp an EFI or is it carburated?

I'm also assuming your Skeeter is a glass boat which is probably close to 400 lbs heavier than mine (if it's 18'). If I had a glass boat, I would for sure upgrade to the Verado.

My uncle is running a Honda 90 hp 4 stroke on his Lund 1700 Explorer and doesn't seem to have much issue with it....in fact, he was the one who towed me back 5 miles back to the resort when my Opti blew up.

As far as the engine tests, not all indicated how much fuel they were carrying...some did though. A few carried between 5 -10 gallons...a 170SF Starcraft (17'8") was carrying 25 gallons and reached top end of 40.6 mph.

I would LOVE to have the $$ to upgrade to the Verado...but don't.

[marine_man]

If you're set on a Mercury & don't want to upgrade to a verado then I'd say your options are pretty limited. A 115 4-Stroke or an optimax, which you already expressed you opinion on.

Given that I'd say it's your only option.

If you're willing to re-rig your boat I'd take a look at a Suzuki or a Yamaha as well - both make good 4 strokes.

A 115 will work on your boat - but you're going to probably burn about as much fuel as your 135 optimax did since it's probably going to be lugging a bit to get that boat up and out of the water. It will work - but the performance (hole shot, speed, ability to do what you want on bigger water when it gets windy) will suffer IMHO.

marine_man

[jerkin'm]

I'm not sure if it's efi or carb..You didn't mention if you were set on a brand new motor or a used or carryover would work for you. I know if it were me, I would rather buy a used motor than have an underpowered boat...

[marine_man]

I would rather buy a used motor than have an underpowered boat...

A very good point - be sure to check out the used market - you might find something your happy with there!

marine_man

[MetroWalleye]

Originally Posted By: jerkin'm

I would rather buy a used motor than have an underpowered boat...

A very good point - be sure to check out the used market - you might find something your happy with there!

marine_man

My Optimax was used and I got burned by it, so I guess I'm a little gun-shy. The problem with the motor wasn't overuse by the previous owner because it had very few running hours on it (40 hours total), but under use. He most likely didn't run his motor enough and the result was condensation and corosion building up in the cyliners which ultimately led to piston rod busting through the engine block.

I'm not completely set on the Merc yet, but I'm told that with the lower gear ratio than the Yamaha that it will have a little more torque out of the hole. It's also a few pounds lighter....I also have the ability to get the brand new Merc at below cost.

Let me ask you a question, when I was younger we had a 18 foot Aluminum Sylvan with a Merc 90 hp. I don't recall any real issues with that boat taking a long time to plane out. Do the new 115 EFI 4 strokes have less power from the hole than do the old 90 hp 2 stroke motors?

Thanks for all the opinions and advice....you're really giving me something to think about/

[marine_man]

4 Strokes in general don't wind up as fast as 2 strokes. EFI helps, but it' still not quite the same in my opinion.

marine_man

[blarkey]

I haven't figured out the actual millage but was on lake Vermillion last year for a week and only burnt one 26 gallon tank and I did a lot of running around . I used to have a 15 1/2 foot smokercraft with a fifty horse and did the same week trip and burnt much more gas.

[Jack Stasney]

I see you guys are talking about "used" motors. I just wanted to point out rebuilds specifically. I've used rebuilds a few times now and have had good luck with them and saved a bunch of money too. If you can find a nice one that someone will warranty as well then you also have peace of mind.

[jhol]

Metro Walley

Not that anyone should set up their rig for the next owner but to throw another angle on your decision you might want to consider going larger with the motor, it will make your resale a ton easier and you will be able to get a lot more out of your rig when the time comes to get a new one. I recently bought a used boat and if the motor was borderline on power I did not give it a second look, I might be in the minority?

Just a thought.

Good Luck