Best Engine for the Money

I have a 1986 Lund Tyee 5.3 with a 1986 Mercury 115 hp tower of power on it. The motor runs fine, but I am considering updating to a newer engine. The boat is an aluminum hull and will take up to 125 hp. I have a 9.9 hp kicker on the back and a minn kota maxxum on the front. I only use the main engine to get on and off the lake. The longest drive will be up to to 5 miles. I fish at two main altitudes, 5500 feet and 9000 feet. Engines run very different at these higher altitudes. I have a budget of $2500 or close to it and want to know what engine in the 90 to 115 hp range is a good investment. I know the 50 hp models and under much better than these larger engines. I like 2 stroke engines a little better than 4 stroke, but I am open to suggestions. I posted here because I have always owned Mercury, but have ran a few smaller Yamaha's and OMC's as well. My brother has a 1998 Mercury 150 hp Optimax that I love, but it is obvously too big for my boat. I am willing to be patient and wait for the right deal. Are there any engines to avoid, are any more reliable than others in this price range. In my area there are a lot of Mercury, Yamaha, and Evinrude engines. Not a lot of Honda or Suzuki engines here. I may even look for another boat with the engine I want and swap the motors out and resell the purchased boat. Your input is appreciated.

I fish at two main altitudes, 5500 feet and 9000 feet.

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A computer controlled engine will adjust automatically to the changes. Two stroke Optimax would be my choice...it seems to be a reliable engine.

I like the Opti's as well, but you might be hard pressed to find one in your budget range unless it was one of the earliest models.

For overall reliability and availability of parts it's tough to beat the carb model 90 horse Merc. Might be the most prolific motor on the planet larger than 50 horses - came on just about every "package deal" out there and stayed in production until 2005 in the US and 2012 in the export market.

You would need to have it re-jetted, but they are readily available and often sell, in great condition, for somewhat less than 1500 bucks.

I'm not fussy about Mercs 115/125 4 cylinder 2 stroke models. They can be "quirky". Aside from the 90 my next step up would be the V6, 2.0L 135 2 stroke (maybe my favourite large Merc of all time - that's just personal though).

A 90 Yami, 2 stroke carb - anything newer than maybe 1986 would also be a fine choice.

So before I ramble on too much, my choices would be a 3 cylinder carb model 90 from either Merc or Yamaha;

An OPTI if you could get a deal putting it in your budget (would stay away from the OMC/BRP ETEC's unless buying new); or,

A V6 135 Merc if your boat can handle the horses.

As you note, it's sometimes difficult to find support for Honda and Suzuki and with Honda they have a nasty habit of discontinuing parts support once they stop building a particular model.

Thank you for the responses, that really helps a lot. I just don't know this hp range very well. Always used 50 hp and under in the past. I would love and Optimax, but probably won't be able to afford one of these. I like the idea of the 3 cylinder carbed merc or yami. I haven't seen any for sale around here for a while though, but I will keep looking. I wish I could put a 135 on it, but I think that would be a little intense for this boat as it is rated at 125. Other than ebay and my local area ads are there any good places to buy used engines? I am in no rush, but will jump on the right deal. I was looking at a 99 Evinrude, but will not buy it now based on your suggestion. I trust mercury and yamaha anyway.

Keep an eye on www.smalloutboards.com (despite the name they sell all horsepowers).

At this very moment they have a nice 1987 or 88 (too lazy to look up the serial ) 90 horse Merc/Mariner listed for $2595.

They ship everywhere, go over every motor quite extensively etc.

At the very least, you can give them a call (number is on the website), give them an idea of what you are looking for/what you want to spend and they will look for you. Have never heard a complaint about their motors or service, so worth a look..

(should have added wrt your last post - a mid-80's to mid-90's Evinrude or Johnson (carb model) is also a nice motor in the horse class you are looking. I own two Evinrudes, an 86 and an 87 - 2.5 horse twin and a 140 horse, 4 cylinder 90 degree looper and love the motors. I'm just not fond of their direct injected 2 strokes or the Johnson 4 strokes that were built by Suzuki. When OMC was going down the tubes - late 90's, in my opinion their product slipped a bit and the direct injected FICHT motors were a nightmare).

Thanks for the response. Yeah the Evinrude I was looking at was a Ficht. I am glad I did not buy. I contacted the website, so we will see what happens. I am sure if I am patient, something will come my way. Thanks again.

I hear this discussion all the time. New OBs cost a fortune to buy and are complicated as all hell (meaning hard to troubleshoot on your own). The older motors--if properly restored--will not only run great and be stone reliable, the cost of buying one, then fixing it up, is a fraction of what a new one costs.

For this reason folks like me do a brisk business in old OBs!

Jeff

Jeff,

What are your favorite motors in the 90 to 125 hp range? I do have the 1986 115 hp inline 6 on the boat already. It runs great, but I don't have much of a history with it. I have gone through the engine and replaced all the hoses, impeller, fuel pump, filter, carbs overhaul, new starter, new water jacket gasket, new trim motor. I know this is old technology, but used for a long time. Would I be just as good staying with what I have? Any known issues with the inline 6 115 hp? Thanks for your response.

Troy

The inline 6 was built for many many years and is a very solid engine when maintained !---------Many people scoff at them because they are " old " I guess.-----Other good solid motors are the 90 / 115 HP 1980's V-4 crossflow engines if they have been refurbished / rebuilt with Wiseco pistons.

The issue I have with the straight 6 (towers of power) are the almost impossible task of trying to find a rotor if you toast one (plus the fact that they were selling for over 200 bucks when they were still available) on the distributor cap models.

The (later) models with the cd ignition solve that issue, but they have old back draft Tillotson carbs that you can't get complete kits for.

So in either case, for the sake of a very very small part that should cost nothing more than a few bucks you have a rather awkward paper weight.

Now, if you want the "look" of the motor to go with a vintage boat, that's one thing, but as a "daily driver" that could be laid up permanently due to "what should be" a simple fix it's not a motor I would hang on the back unless it was because I already had it - I certainly wouldn't buy one if I was searching for a motor for the average boat.

But I feel the same about any motor with obsolete/unavailable parts which is also why I stay away from Honda's - probably the best 4 strokes out there but when they discontinue the motor they also cease parts production, so the clock is ticking until the stock on hand runs out..

The ficht 90/115 engines do not suffer the bad reputation and problems as the V-6 engines did. I have a customer with a 99 model 115 that has over 1500hrs on it and all its ever had done was impellers and plugs and he is a commercial fisherman!!!! The 115 would make a great engine and will troll all day long..

..."The (later) models... have old back draft Tillotson carbs that you can't get complete kits for."

You don't need a carb kit--that's just a waste of money.. All you really need is a readily available needle and seat (sold on this site). The float bowl gasket comes off in one piece if one is careful, and no other parts are needed--just clean 'em up! But I always remove that dopey back drag hose, plug the hole in the float bowl, and put a screw in the hose to block it off.

Agreed on that fragile, hard to find, grossly expensive rotor deal. (I was lucky to have not broken the one I worked on. Wheeew!) Other than that, a reasonably good condition, properly restored "Tower of Power" can run for decades--they made them RIGHT. And the cost of that is a mere fraction of what a new OB costs. That goes for any "Tower of Power", from the original (made from three sets of Merc 350 twin blocks) to the last Merc 1500--the pinnacle of crossflow design cylinders.

Jeff

We can all find examples - my best buddy has a 1990, 90 horse Force WITH the original, and "still functioning" Autoblend system on it - and used the boat alot.

That doesn't mean I would recommend a 90 Force with Autoblend to someone who is "looking" for a motor.

I think we all tend to get a little off track. If in the context of someone looking for a replacement motor, the question becomes (given the hundreds of choices) what motor would be best from ALL standpoints - reliability, availability of parts, known history of the model line/run etc.

It's one thing if you "acquire" something, but I think his questions was "what would one of us seek out" in that horse class...

A 1986----115 HP is just an excellent motor.-----Very simple and easy to maintain.--------Years from now some folks will agree to that.

Years from now some folks will STILL agree to that! And she'll still be running strong.

Jeff

Thanks for the discussion so far, it has been very interesting to hear all the opinions. It is kind of a loaded question. I personally just don't like the look and age of the tower of power. I would prefer a little newer motor that won't leave me stranded in a storm on the bigger lake I fish on. The waves can get 6' tall and I need the engine to be reliable. To update everyone, I found someone to trade motors with. I am upgrading to a really nice 1998 115 hp carburetor Mariner. I have thoroughly checked it out and it seems to be in excellent condition. I am installing my 1986 Tower of Power on his boat plus giving him $1200 bucks for his engine, controls, and a stainless prop. He is just selling his boat anyway and needed some cash right away. With it being winter, he hasn't been able to sell it, so we made a deal. I was hoping for a 90 hp 3 cylinder, but I will give this 4 cylinder 2+2 model a try. I have also heard good things about them.

They are a decent model. I thing maybe guyjg owns one (?).

If you are not familiar with them the do kinda "hitch" when the full 4 cylinders kick in/out as you accelerate and decelerate - which is totally normal.

That is what I understand, that you kind of feel a surge when the other two cylinders kick in/out. When I heard about the 2+2 concept, I worried the 2 cylinders that don't have an idle port would not be lubricated, but I guess they have a small fixed port that allows enough fuel to lubricate things. Didn't Yamaha come up with this design? From what I hear, they are a little different, but reliable and run well. Like I said, in a perfect world I would have picked the 3 cylinder 90 hp carburetor model, but this was in my price range and available.

Yes, this is a Yamaha design and build (Merc reluctantly released details of how much Yami built for them a few years back during a court case).

And while I love the 3 cyl 90, I think you will be well pleased with this motor if it runs well for you. Lot's of guts.

If you are not familiar with them the do kinda "hitch" when the full 4 cylinders kick in/out as you accelerate and decelerate - which is totally normal.

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If its set up correctly you will never feel the other cylinders "kick in" unless your pulling a skier or tube.

I was hoping for a 90 hp 3 cylinder, but I will give this 4 cylinder 2+2 model a try.

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Graham is right...I like mine. You hardly notice the "kick" of cyls. 3+4 coming to life if you don't *****foot around w/the throttle. Cyls. 3+4 get plenty of lubrication. I am going to add an in-line fuel shutoff valve so I can let the carbs run dry after loading on the trailer. I suggest that you do the same if you have a semi-permanent fuel hose connection like I have.

Guyig,

Thanks for the response about your motor. I like the idea of an inline fuel shutoff. I still haven't decided whether or not to use the built in 25 gallon tank or just use my portable tanks, but if I use the built in I will definitely use your idea.

Next step will be to find the correct prop for my boat. The boat a Lund Tyee 5.3 17'6" is just over 1000 pound deep v hull in aluminum. With the engine and fuel and gear it will be around 1500 pounds plus people. I fish at higher altitude lakes which make it more difficult to get the rpms up due to lower oxygen levels. 3500-9000 feet elevation. With 9000 feet being my favorite lake. The boat is a completely different boat with the old engine at 3000 compared to 9000 feet elevation. I will re-jet it for 3000 feet, but not sure where to start for prop pitch. I think it has a 14" x 17 pitch prop. Good place to start.

W/gear, fuel and you the wt. should be between 1500-1700 lbs. I believe your WOT is 5200 RPM. I'm running a 23P alum. prop. on a FG ProCraft 17.5'; loaded wt. is 2300 lbs. You might want to rethink the altitude for rejetting the carbs. I think jets for 9000 ft will make it run richer at 3000 feet...use more gas. Talk to the local merc. rep. about the pros/cons. Good luck

thanks...wasn't 100% sure.

Yes, my logic in jetting it at 3000 feet was that is the lowest elevation I will be using it at. It won't run as strong at 9000 feet, but I also don't need to run as fast up there, just to get to my fishing spot. If we do any watersports it will be at the 3000 foot level where I need optimal performance. I will probably use a lower pitch prop for the higher altitude lake so it will even plane.

Keep us posted on how this engine performs for you.----------Are you doing any maintenance / checks on this new to you motor or are you just launching and trusting that everything is AOK with it ??

I absolutely will go through everything before i ever put it on the water. New impeller, change the lower unit oil, and check everything else out. I won't trust that anything was actually done unless I see it for myself. I will keep you posted on how the motor does. I am excited to try it out.

This is a really old thread, but I wanted to let everyone know my experience with the Mariner/Mercury 115 HP 2+2 engine. After having a little problem with the stator initially I have really enjoyed this motor. It is a beast a lower altitudes and pushes my boat around 55 mph. At the higher elevation lakes (9000 ft) it slows down to 35 mph, but still runs good. I had a difficult time getting it to idle smoothly off of full throttle the first year I had it. I rebuilt the carbs and the second year it runs a lot better. I personally am not a big fan of the 2+2 cylinder effect. It runs on two cylinders up to around 1800 RPM with the top two carburetors only having the idle jets, then the other two lower carbs get enough vacuum to start sucking fuel through the high speed jets giving you an instant kick to higher power. If you are trying to run at a mid throttle this becomes quite annoying as it goes in and out of the power band. I would prefer a motor with all the carbs having idle jets and smoothly accelerating. The motor has also been a little finicky about getting it to accelerate from idle to wide open throttle without stalling a little at higher altitude. I finally got it dialed in with very minute adjustments until it is where I can deal with it. The motor also is not very fuel efficient. I was surprised that I was using significantly more fuel than my brother with his 150 hp Optimax on a boat twice the weight of mine. My fuel consumption was twice his. That is comparing a carb engine to a direct inject engine though. I would not be afraid to say the motor is solid and reliable, but a little different. I have the opportunity to buy a 2000 Yamaha 100 hp fourstroke for $1100, so I am going to upgrade at this time. I just thought I would give my two cents on owning this motor.