Mini boat engine choices

[Tom Brown]

I was originally going to direct this at Dave but there are probably quite a few people with mini boat projects that will have some good input on this.

My original thought on power was an OMC 75 Stinger. As best I can tell, there isn't a Stinger worth having at a reasonable price.

I know of a 75 Evenrude Hustler (same as a Stinger) and it will be in mint condition since the dope dealers who own it haven't used it in 30 years. I'd have to buy the whole boat and motor, though. I'm sure they'd want $5K for the 15' Baja and Hustler. Actually, it might still be worth it.

That leaves me thinking any OMC L3 in decent shape would be a good choice for my 12. In fact, I'm thinking about just leaving the Tohatsu 40 on there. If it will plane and cruise comfortably, I won't be all that concerned about the top end.

I'm a Mercury guy but OMC cleans the floor with Merc in those sizes.

What about Yamaha? Do they make an engine that might be appropriate? Anyone else?

Any opinions on power options for a 10' or 12' mini boat? I'm thinking power to weight will be the key so no twin Honda 225 mills.

 

[RiverDave]

Tom, I know jack shit about little outboards, or even big outboards.. LOL

You let me know what the lightest (absolute lightest) 40 - 75HP engines are.. I'm thinking 75 for the 12 minimum.. 50 for the 10 if I can get it light enough.

The 10'ers, generally are the same speed with a 30 - 35 - 40..

My old one felt under powered to me, I'd rather not go the 40 Tohatsu route again.. Unless it's a built little tunnel motor or something putting out like 60 - 70 HP.

RD

 

[Tom Brown]

The thing about outboards is that, back in the 80s, a regular 60 hp OMC fishing engine would typically beat down an 80 Merc like a brush fire. It was embarrassing. OMC was the way to go and the L3 engines were totally the deal. In particular, later L3 engines with integrated trim pump, etc. were legendary, IMO.

These days, I don't know what's up. I'd like to go with an old L3 because they were the thing to have in my youth. There are probably newer, better engines by now, though. I'm hoping someone will step up.

There was a guy on Scream & Fly who converted a regular L3 into a Stinger. I'm pretty sure the L3 are all steel sleeves so there's no plating to worry about when changing the port timing and such. On the other hand, as I get older I've learned to appreciate unmodified engines. Turn the key and go. It sucks a whole lot less than tinkering with your motor every weekend.

Where's Al Stoker when we need him?


Oh... as far as motor choices from back in the day, here's how I would rate outboard engines from the 1980s.

50hp - OMC L2 looper - Good engines. Not long on torque but strong for the size. If this is the most weight your boat can take, go with a 55.

60~75hp - OMC L3 looper - Dominate this segment. The 75 Stinger/Hustler were the cream of this crop but the 70 fishing engine isn't that far off on performance.

90~140hp OMC V4 - The OMC 90 had worlds more power then the L3 but was quite a bit more weight. If you can float a 90, don't bother... go for a 140 at the same weight and die with a bigger smile.

150hp - OMC V6 - More displacement than the Merc and lots more torque than Mercury's little 2.0. Everyone loves the XR2 and it will beat the OMC 150 on top end performance but I'll take an OMC fishing engine with it's better low end grunt and the very small weight penalty it brings.

200~225hp - Merc V6 - Both the Merc 2.4 and 2.5 were very strong, although the 2.5 is lots stronger. The Merc 2.4 has a questionable top bearing so I'd go with the 2.5 here. The 225 doesn't seem to have all that much more performance than the 200 making a 225 hp upgrade almost irrelevant for 200 owners.


Does anyone have different views or perhaps some more current information? I'm thinking 4 strokes aren't all that interesting on a tiny boat due to the weight so we're probably looking at a 1990s engine as the most recent appropriate engine.

 

[Yellowboat]

in the mid 90s merc made a 40 hp that was actually a 60 with a restrictor plate. they did it to win some races. If you can find one of those, thats the way the go.

we had one for awhile, but sold it for some reason or another.

 

[RiverDave]

in the mid 90s merc made a 40 hp that was actually a 60 with a restrictor plate. they did it to win some races. If you can find one of those, thats the way the go.

we had one for awhile, but sold it for some reason or another.

Do you know what the model was, or some way to search for that?

RD

 

[Faceaz]

in the mid 90s merc made a 40 hp that was actually a 60 with a restrictor plate. they did it to win some races. If you can find one of those, thats the way the go.

we had one for awhile, but sold it for some reason or another.

Doesn't make sense. So they took the heavier 60 & choked it to 40 horse. Why wouldn't you just wtb the 60 that doesn't have the restriction?

 

[Faceaz]

IMO you can't go wrong with the Yamahas. If I didn't have a garage loaded with OMC shit, I would make the switch. Only one I had was a 150, but that thing ran perfect till the day I sold it - never an issue. Pushed our little 18' Advantage to around 60.

 

[Yellowboat]

racing class rules... had to be a 40 hp stock motor... one of those deals where every one was runing motors with displacement in the high 20s ci and here comes one that was in the 40s. It was banned at the end of that year lol. Bigger prop= more water moved.


RD it was thier comm'l model with the big foot package, only unlike the 60 hp big foot, it did not have any big foot labling. Look for a 40 hp with like 40 something ci displacement and a huge lower end. it should be the same displacement as the 60 hp that year( or maybe it was the year before). I think they made it 93 and 94. I think we might have the invoice, I'll see if I can find it.

 

[Outdrive1]

I was watching some sunrise hd show this morning while getting ready. They were cruising around the canals in Venice. I was amazed that almost all were outboard boats, and most had Yamaha's on them.

Id like rumble through there in a loud ass big block something.

Sent from the mother f____ing Droid.

 

[Mondorally]

I was watching some sunrise hd show this morning while getting ready. They were cruising around the canals in Venice. I was amazed that almost all were outboard boats, and most had Yamaha's on them.

Id like rumble through there in a load ass big block something.

Sent from the mother f____ing Droid.

LOL, I've walked over many a bridge in Venice thinking the same thing...

 

[Yellowboat]

LOL, I've walked over many a bridge in Venice thinking the same thing...

I had a friend that had a house on lake of the pines( google it) its a small private lake/water front community. Anyways long story short he was moving out do to the HOAs. the last thing out of the house was his blown eliminator that had zoomies on it. At about 5ish in the morning on a suday at 1st light( last day he was there), we put it in the lake, left the truck running, 2 quick passes, put it back on the trailer and left.

good times.

 

[B---S---]

I would do one of these with a Vdrive http://www.h1v8.com/page/page/1562068.htm

 

[Froggystyle]

These days, I don't know what's up. I'd like to go with an old L3 because they were the thing to have in my youth.

This was "the thing to have" in my youth...

 

[pronstar]

You could go the baller-route and run twin or triple 20-hp outboards :thumbsup

 

[barbigrl]

I am a mini boat owner Tom.......but I don't know shit about motors and stuff. I just want to look cute in it.

 

[RiverDave]

You could go the baller-route and run twin or triple 20-hp outboards :thumbsup

There is already one with Twin 30's..

RD

 

[Tom Brown]

in the mid 90s merc made a 40 hp that was actually a 60 with a restrictor plate.

What would be the advantage of running a 60 with a restrictor plate versus just running any Merc 60 from the era?

I am a mini boat owner Tom.......but I don't know shit about motors and stuff. I just want to look cute in it.

You're killing me here. My goal is to not look cute in mine, if at all possible.

I've been telling everyone the mini boat isn't really for me, I'm building it for my nephew.

 

[Tom Brown]

Hey, when did Yamaha start building the Merc small horsepower engines? that was in the 1990s, wasn't it?

 

[Tom Brown]

I'm looking at Yamaha's midrange specs and it looks like the biggest engine they make with a 15" tower is 25hp.

http://www.yamaha-motor.com/outboard/products/subcatspecs/2/specs.aspx

It looks like a serious re-power is going to require cutting down a 20" mid.

Some of the racing heritage outboards come with 15" mid sections but I can only imagine how tough it's going to be to find one in reasonable shape.

Lastly, I wonder if a Yamaha 70 engine clamp will even fit on a mini boat transom? Seriously. I'd want to measure it to make sure the bottom of the clamp is above the bottom of the hull before pulling the trigger on one.

 

[RiverDave]

Those are way heavy Tom.

 

[75 Spectra V-Drive]

Why not run a Honda Aquatrax turbo motor and jet? saw one on Craigs List for $2500 complete? Too heavy?....................or just too GAY???

 

[Tom Brown]

Those are way heavy Tom.

Oh yeah. That's why I'm a fan of the old L3. I think it's tough to beat.

 

[RiverDave]

What exactly is an l3?

 

[Tom Brown]

Inline 3 cylinder. OMC, specifically.

My family has had 60, 65, and 70hp versions of this engine. A neighbor at the lake has an Evenrude 75 Hustler (same as the 75 Stinger).

I wouldn't say they are the same but the difference between them is not all that big of a deal. In particular, the OMC bottom end grunt is really impressive for the engine size.

... but finding one that isn't used up will be a task.

 

[RiverDave]

Inline 3 cylinder. OMC, specifically.

My family has had 60, 65, and 70hp versions of this engine. A neighbor at the lake has an Evenrude 75 Hustler (same as the 75 Stinger).

I wouldn't say they are the same but the difference between them is not all that big of a deal. In particular, the OMC bottom end grunt is really impressive for the engine size.

... but finding one that isn't used up will be a task.

How much do they weigh?

RD

 

[Tom Brown]

How much do they weigh?

220#

 

[Tom Brown]

Here's one that's currently owned by a relative of Kim Hanson.

http://alberta.kijiji.ca/c-cars-veh...s-Try-Haul-w-70-HP-Johnson-W0QQAdIdZ253233212

That's a 20" mid, though. I could cut down a mid easy enough but I don't know if anyone re-spines those driveshafts.

 

[TomD]

Here's one that's currently owned by a relative of Kim Hanson.

http://alberta.kijiji.ca/c-cars-veh...s-Try-Haul-w-70-HP-Johnson-W0QQAdIdZ253233212

That's a 20" mid, though. I could cut down a mid easy enough but I don't know if anyone re-spines those driveshafts.

Cut and weld.:thumbsup

 

[Tom Brown]

Cut and weld.:thumbsup

The driveshaft?

I understand they can be friction welded but the big V6 Mercs don't do very well with a welded driveshaft. Maybe the little OMC will stress the weld less.

There are a couple of guys who can re-spline the driveshaft of a V6 Merc. I'm sure they could do the little driveshaft too but I wonder if they would bother.

 

[Mondorally]

Evinrude an option? Here is a 60hp, 20" mid, weighs 240lbs

http://www.evinrude.com/en-US/Engines/ETEC_INLINES/ETEC_60_INLINE

 

[Faceaz]

Evinrude an option? Here is a 60hp, 20" mid, weighs 240lbs

http://www.evinrude.com/en-US/Engines/ETEC_INLINES/ETEC_60_INLINE

Great little motor right there, burns so clean there's virtually no smoke. Al has one in a tank inside their store, you don't even get a hint of fumes when it's running.

 

[Tom Brown]

Evinrude an option? Here is a 60hp, 20" mid, weighs 240lbs

I'm a big fan of the e-tec but the Honda 60 is spec'ed at 239#, dry weight.

The Yamaha weighs in at 247#.

... so it looks like there is no weight advantage in the 2 stroke.

 

[RiverDave]

220#

I'm looking for like 160 lbs.. LOL

The 40 Tohatsu's are around 130 if memory serves? Gaining another 100 lbs isn't an option on a 10' Schiada.. I think it would struggle to float, amongst everything else. (Boat balance etc..)

RD

 

[Tom Brown]

Can't you just move your subwoofer and heavy billet shit further forward?

 

[RiverDave]

Can't you just move your subwoofer and heavy billet shit further forward?

No subwoofer, and the bulkhead is in the boat now.. LOL So nothing is going forward of that.. maybe a ballast tank, I dunno.. it is after all a mini ski race boat..

The key is to keep it light though, and 220 lbs on the transom ain't light..

RD

 

[Tom Brown]

By the way, the Tohatsu 40 seems to weigh in at 160#.

http://www.tohatsu-outboards.com/tohatsu-40-HP.htm

It's becoming increasingly clear that I'm going to end up just running the 40hp engine on my Daytona and that it will be just fine.

 

[RiverDave]

By the way, the Tohatsu 40 seems to weigh in at 160#.

http://www.tohatsu-outboards.com/tohatsu-40-HP.htm

It's becoming increasingly clear that I'm going to end up just running the 40hp engine on my Daytona and that it will be just fine.

I think the earlier ones were 2 cylinders and weighed less. I'm guessing on the weight of it, but I know my old one didn't weigh 160 lbs, because I could pick it up and carry it around.. If it weighed 160, I don't think I could do it.

RD

 

[whiteworks]

Just hop up a Tohatsu, pretty sure you can damn near double the HP. How long will it live will depend on how much money you dump into good parts. Call Stoker

 

[Tom Brown]

A couple of sites are showing the 130# number you cited.

Mine is a 1985 so it looks like it is a 2 cylinder also.

Yeah, I'm done pondering engine swaps. At least for now. I have no plans to beef it up with any billet or trick accessories. Well, I might install a couple of gauges just because I like to have depth and speedo. Maybe volts...

 

[RiverDave]

Just hop up a Tohatsu, pretty sure you can damn near double the HP. How long will it live will depend on how much money you dump into good parts. Call Stoker

Does Stoker build up little tohatsu's?

RD

 

[whiteworks]

Does Stoker build up little tohatsu's?

RD

I dont think he cares what it is as long as the check clears

 

[Tom Brown]

You don't need Al Stoker, Dave. Just bolt some carbs from an 80hp on there. That will double your power right there. :thumbsup

 

[Tom Brown]

Dave, I'm not kidding here, if you decide to modify your engine, I strongly recommend you pick up a second engine and keep it stock. That way you'll have a standby that will always run.

Seriously, modified outboards are rarely reliable.

 

[spectras only]

Tom , I'd find a Konig or Crescent 500 . Nothing beats the sound of a little outboard that sounds like an F1 car . Friend of mine raced a little hydro with a Koenig 500 back in the 70's.
Listen to this clip YouTube - Area 31 Racing: 5 Port 500cc Konig powered hydroplane - race 1 Aug 2008

 

[hotrod56cars]

I haven't been dealing with outboards for very long but my friend Frank has worked with outboards for decades. Frank really likes OMC's from the 80's and 90's for their reliability. Yamaha's are supposed to be real good engines as well.

I recently shipped a 1986 50HP VRO Johnson to Canada and it weighed 192 pounds.

 

[RiverDave]

Ask Frank what kind of outboard weighs 160 pds, and will put out 50-60HP.

RD

 

[Tom Brown]

Nothing beats the sound of a little outboard that sounds like an F1 car .

Now that's the practicality I've been looking for. :thumbsup

 

[Yellowboat]

Ask Frank what kind of outboard weighs 160 pds, and will put out 50-60HP.

RD

some of the older merc short shaft 60 hp were about that.

older 2 cycle= the win.


I think only the nissan and the toshiba( both the same) 50 HP are the only current motors that are less then 175# for that hp range.

 

[whiteworks]

Those litte evinrude motors that they run on the SST 45's might be the way to go.

 

[Tom Brown]

some of the older merc short shaft 60 hp were about that.

Are you sure?


1987 Mercury 35, no p/t,remote... 214#

1991 Mercury 50/60hp...217#

1977 Mercury 50hp ...168#

Mercury 40 classic(2cyl)...176#

Mercury 40hp(3cyl) + 50 classic...199#

Mercury 60hp....219

Mercury 60hp big foot... 242