Outboards 2009 - HP, Weight, Make Comparison

[rwatson]

Just did a chart of motors between 20 and 150 hp, with weights, by make. Thought I would upload it in case anyone is interested.

[ririzarry]

Very helpful...

Thanks,

Rob

[Fanie]

Interesting to note up to a 60hp the weight remains relative low, then it shoots up by quite a bit. The remaining factor to consider is the price...

[rwatson]

Interesting to note up to a 60hp the weight remains relative low, then it shoots up by quite a bit. The remaining factor to consider is the price...

Wish I could get some prices - they seem to be "secret distributor business".

Varies so much from country to country too

[Fanie]

I hear some good things about these Tohatsu motors.
Some prices under the specification tabs here - in US$
http://www.tohatsu.com/outboards/index.html

[rwatson]

I hear some good things about these Tohatsu motors.
Some prices under the specification tabs here - in US$
http://www.tohatsu.com/outboards/index.html

I just put the Tohatsu specs on that chart.

You are right, they have a very good weight/power ratio at least

[Itchy&Scratchy]

I may be wrong here, but I think Tohatsu are made by Yamaha.
J

[mwatts]

I may be wrong here, but I think Tohatsu are made by Yamaha.
J

No Yamaha's lower end brand is Selva. Tohatsu's are built by Nissan. I don't know if they are 1:1 the same though.

@RWatson: Did you compare identical motors? Because long shaft / short shaft, tiller / no tiller, powertrim yes / no, dryweight or ready-to-run all make a difference in weight. Otherwise it's like comparing apples & pears.

For instance, if I look up the 2009 specs for a Yamaha F20B, I see it weighs 51.7 Kgs, not 61, and an F30 83.8 Kgs, not 99.

Are the Tohatsu's in the chart the 4-strokes or the 2-stroke Direct Injected (TLDI) engines?

[rwatson]

All the 20 hp are the same weight with prop, and they *are* 61 kg There are four F20B models, and they all weigh the same,. Weight is quoted as Weight (kg) with prop. 51.7 ~ 60.7 , which I take means around 51-61 kg, so I pick the highest

http://www.yamaha-motor.com.au/marine/index.htm?marine.asp

Yamaha 20 HP (4 Stroke)
Model Weight with prop (kg) Transom Height MM
F20BEPL 60.7 508
F20BEHPL 60.7 508
F20BMHS 60.7 381
F20BMHL 60.7 508

There are 4 F30's quoted (not one) and the weights are not 83.8 kilos
http://www.yamaha-motor.com.au/marine/index.htm?marine.asp

F30BEHTL 104 536
F30BEHTL 104 536
F30AEHTL 95 533
F30AETL 90.4 533

so the average weight is 98.35 (99)

There is no quoted dryweight V "ready to run" figures I can see, unless you add the Oil Pan Capacity (2 litres) which is just nit picking. Tiller arms are not significant.

You have to assume powertrim is within the maximum weight for the small engines, and standard on all engines over a certain size ( maybe thats why the jump in weights over 30, and weight range for the low enders)

All updated figures with web site addresses and features are welcome though. I am happy to check all figures in the chart as it makes it more usefull to everyone

[tom28571]

The main thing you point out with these charts is that it is wise to look at the actual specs of motors rather than listen to general beliefs on the weights and power of outboards. Some 4 strokes are heavier than 2 strokes of the same "rated" power by only a couple percent.

What the actual developed HP of these engines is, is not often known so accuracy of comparisons suffer.

Mid power range Suzuki 4 strokes are much heavier than their counterparts from other manufacturers. They are also much higher displacement than their counterparts so do we trust the power ratings? A Suzuki 60 is over 45% heavier and 25% greater piston displacement than other similar engines. This does not look reasonable. Apparently the Suzuki is highly detuned and derated. Where weight is not a factor, the Suzuki 60 looks like a rugged engine.

[rwatson]

rather than listen to general beliefs on the weights and power of outboards.
.

Hmm, can we not trust the facts quoted by manufacturers ? They get validated by lots of different people. I wouldnt have thought they would fib much.

Some 4 strokes are heavier than 2 strokes of the same "rated" power by only a couple percent. .

yes - whats the point you want to make ?

What the actual developed HP of these engines is, is not often known so accuracy of comparisons suffer..

I really am not sure what you mean by this. Could you explain more please ?

Mid power range Suzuki 4 strokes are much heavier than their counterparts from other manufacturers. They are also much higher displacement than their counterparts so do we trust the power ratings? A Suzuki 60 is over 45% heavier and 25% greater piston displacement than other similar engines. This does not look reasonable. Apparently the Suzuki is highly detuned and derated. Where weight is not a factor, the Suzuki 60 looks like a rugged engine.

No - its only the 60 that is "much heavier"
The Suzuki 60 is 1298cm Displacement, and weighs 160 kilos, way over comparable motors. I cant think of when weight isnt a factor, but I would be interested in how the weight makes it more rugged. I have no experience with that engine.

The reverse is true for the larger powered motors

for example

Suzuki
DF 90A/80A/70A 4 Stroke
Multi point Sequential Electronic Fuel Injection
Maximum Output: 90hp (66.2kW) / 80hp (58.8kW) / 70hp (51.5kW)
Cylinders: In-line 4
Displacement: 1502cm3 (91.6 cu. in.)
Weight kg: L: 160
X: 164

Yamaha
NEW F80BETL (4 Stroke)
Engine Type 16-Valve Direct Action Inline 4 Cylinder
Displacement cm³ 1595
Bore x Stroke (mm) 79 x 81.4
Output (hp) 80
WeWeight (kg) with prop. 172 ~ 181

Here the Yamaha has a bigger displacement than the Suzuki, and weighs more. It looks like the Suzuki 60 is just a detuned 90/80/70 . is this better or worse ?

All thoughts appreciated.

[mwatts]

All the 20 hp are the same weight with prop, and they *are* 61 kg There are four F20B models, and they all weigh the same,. Weight is quoted as Weight (kg) with prop. 51.7 ~ 60.7 , which I take means around 51-61 kg, so I pick the highest


No, it doesn't mean they all weigh same. It means Yamaha has been a bit lazy, and the short-shaft manual-start 20HP weighs 51.7 Kgs, and the long-shaft electric-start with tiller 20HP weighs 60.7 Kgs. Quite a big difference for motors this size.


There are 4 F30's quoted (not one) and the weights are not 83.8 kilos

Yes, you're right about that. ;)

Tiller arms are not significant.
Look at these two engine's:

Model Weight
F30AEHTL 95
F30AETL 90.4

The difference (the 'H') is the tiller handle. It apparently weighs 4.6 Kgs. I think that's significant.


All updated figures with web site addresses and features are welcome though. I am happy to check all figures in the chart as it makes it more usefull to everyone
You're doing a good job. ;)

[Fanie]

The difference (the 'H') is the tiller handle. It apparently weighs 4.6 Kgs. I think that's significant.
Seems the 'H' stands for handle. There's probably a steering in that tiller for that weight ;)

[rwatson]

Model Weight
F30AEHTL 95
F30AETL 90.4

The difference (the 'H') is the tiller handle. It apparently weighs 4.6 Kgs. I think that's significant.

4.6 kilos significant ?????

Come ooooooon!.

You will be carting more beer than that - just put it in the cooler up in the bow!!! :eek:

[Wynand N]

I may be wrong here, but I think Tohatsu are made by Yamaha.
J

No Yamaha's lower end brand is Selva. Tohatsu's are built by Nissan. I don't know if they are 1:1 the same though.

Wrong on both counts;) Perhaps as a Tohatsu dealer I can shed some light on these magnificent motors...

Tohatsu is build by Tohatsu who incidentally is the biggest and oldest outboard engine manufacturer in Japan. In some markets the Tohatsu is marketed as a Nissan and this may come as a shocker to those believing in the American dream. All Mercury's two stroke engines from 50hp down to 2.5 are built by Tohatsu and are just badge engineering. Mercury's four stroke are build by Tohatsu.

I will be more than happy to supply spec/data on the engines when asked since I have everything at hand as a dealer.

As a sidenote; due to the high engine power/weight ratio and reliability of Tohatsu, they are the engines of choice in the ZapCat and Thundercat international surf racing classes...

[Wynand N]

Are the Tohatsu's in the chart the 4-strokes or the 2-stroke Direct Injected (TLDI) engines?

Looked a bit mixed in the charts;

25hp is on par for the plain two stroke short shaft
30hp at 72kg is a four stroke shorty (71.5kg)
40hp is a TLDi two stroke (93.5kg) short
50hp also TLDi two stroke at 93.5kg (plain two stroke short = 72kg!)
70hp is a TDLi two stroke at 143kg - long
90hp also TDLi two stroke at 143kg - long
115 is a TDLi two stroke at 173kg - long

Just for the interest, here are some weights of plain two strokes by Tohatsu

70hp = 105.5kg - long
90hp = 135kg - long
115hp / 120hp = 164kg - long
140hp = 164kg - long

[rwatson]

They must have a special South African Models :)

http://www.tohatsu.com/outboards/115tldi_spec.html
quotes the 115 hp as 178 kilos, dont know where you got 173, but not a lot of difference

All the other weights on the chart were spot on, but rounded up to next Kilo.

The two stroke figures are now included on the chart. They look about on par with the Yamaha.

I was a bit worried about the figure for the 140 HP 2 stroke, even the Yamaha 115 weighs 193. But according to http://www.tohatsu-outboards.com/tohatsu-140-HP.htm, that is correct

WHOOPS - READ THE FINE PRINT, THE 140 2HP IS NO LONGER AVAILABLE ACCORDING TO THAT LAST WEB SITE

[tom28571]

Hmm, can we not trust the facts quoted by manufacturers ? They get validated by lots of different people. I wouldnt have thought they would fib much.


yes - whats the point you want to make ?


I really am not sure what you mean by this. Could you explain more please ?


No - its only the 60 that is "much heavier"
The Suzuki 60 is 1298cm Displacement, and weighs 160 kilos, way over comparable motors. I cant think of when weight isnt a factor, but I would be interested in how the weight makes it more rugged. I have no experience with that engine.


--------------------
Outboard manufacturers have often fibbed about their power ratings. Maybe not so much now as in the past.
------------------------------

----------------
The point is that many people always assume that 4 strokes are much heavier than 2 strokes. I only point out that this is not always so.
---------------------------------------

----------------------
Only what I said above.
----------------------------

--------------------------------------------
Since the Suzuki 60 appears to be the same motor as its much more powerful sisters, it appears to be a detuned version. Detuned engines are generally considered to be more reliable and rugged than their more optimized competitors. Ask any mechanic, especially those responsible for racing engines.

I am not challenging any of the data or statements you made and thought my comments were self explanatory. I do deal with outboards regularly and am interested in comparisons. I do trust the weights given by manufacturers but when specifying a motor of given power for a boat, need to look closely at the specs of those available to avoid space and weight problems.
---------------------------------------

[rwatson]

I wasnt "having a go" at you Tom, just trying to educate myself a bit

Outboard manufacturers have often fibbed about their power ratings. Maybe not so much now as in the past.

I guess we will have to apply some faith in consumer law till we can do some tests. The thing I would like to see is the power curve of each of the engines. Maximum power at high revs makes for a short lived engine.

What we need is a separate authority to test newly purchased outboards to verify the figures. This would confirm to the buyer that the engine they bought was up to spec, and provide realistic HP figures.

The point is that many people always assume that 4 strokes are much heavier than 2 strokes. I only point out that this is not always so..

Well, if they arent heavier than two strokes, basic engineering principles mean there is a problem with one of the engines.

Since the Suzuki 60 appears to be the same motor as its much more powerful sisters, it appears to be a detuned version. Detuned engines are generally considered to be more reliable and rugged than their more optimized competitors. Ask any mechanic, especially those responsible for racing engines.

Re the Suzuki 60, the 60,70,80 and 90 are all 4 cylnders
The 60 Hp = Displacement: 1298cm3 (79.2 cu. in.) (DF60)

The 70 Hp = Displacement: 1502cm3 (91.6 cu. in.)

My take is that there is no detuning - just smaller capacity. Theoretically you could re-bore the block on the 60 hp and make it a 90 in simplistic terms.

That in itself wont make it more reliable or more robust. Its just a marketing ploy to "fill in the range"

I .... thought my comments were self explanatory.

Well, I didnt understand what you meant by "What the actual developed HP of these engines is".

Is "developed HP" different than just plain "HP" ?.

I understand that the HP output can be ruined by a bad prop choice, and that HP takeoff figures can be from the Prop shaft, or the Crankshaft and produce different figures. I was just trying to get a bit more explanation.

I do deal with outboards regularly and am interested in comparisons. I do trust the weights given by manufacturers but when specifying a motor of given power for a boat, need to look closely at the specs of those available to avoid space and weight problems.

Good - the more input we get, the better thre information.

[tom28571]

As far as I know, we in the US don't have any controlling entity that can enforce HP ratings as well as many other specs that we might like. I, for one, will happily do without more government intervention. There are industry standards that help to standardize such things. Mercury was once famous for under-rating their outboards. It let the Merc 10 run on lakes where HP was limited as well as making the Merc so much faster than the competition at the same "HP".

The rest is just pot stirring. No problem.

[marshmat]

I don't think there's anyone in the US actually "enforcing" hp ratings, but my understanding of the industry standards is that an engine has to be within 10% of the claimed horsepower ratings. Outboards are supposed to be rated at the prop shaft. Example- a few years ago ('99 or so), there was a Merc 90 and a Yamaha 100 that were built on the same line, the powerheads being identical in all respects. Both actually produced about 96 hp at the prop. Merc called its version a 90 because a lot of boats had a 90 hp rating, while Yamaha decided to market "a bit more power" at the same price as a 90.

[tom28571]

I don't think there's anyone in the US actually "enforcing" hp ratings, but my understanding of the industry standards is that an engine has to be within 10% of the claimed horsepower ratings. Outboards are supposed to be rated at the prop shaft. Example- a few years ago ('99 or so), there was a Merc 90 and a Yamaha 100 that were built on the same line, the powerheads being identical in all respects. Both actually produced about 96 hp at the prop. Merc called its version a 90 because a lot of boats had a 90 hp rating, while Yamaha decided to market "a bit more power" at the same price as a 90.

Matt,

My points exactly, and this filters all through the hp range and names on the decal.

[Fanie]

I will be more than happy to supply spec/data on the engines
So Wynand, what will it take to actually get the info I requested from you :rolleyes: - I was under the impression you are a dealer :confused:

I, for one, will happily do without more government intervention.
It is no where more true than here Tom. Anything with a 15 hp motor here has to be surveyed, yearly :( It just about making money and nothing else.

[Jack B]

[QUOTE=rwatson;301306]Hmm, can we not trust the facts quoted by manufacturers ? They get validated by lots of different people. I wouldnt have thought they would fib much.


Interesting little game of ping pong this.
We recently built a boat using the Cummins 425hp QSB 5.9 engine. When launched the trim was all messed up and we had to do a lot of remedial work. Eventually we ended up weighing items, including the complete boat to try and get the trim right.
The end of it all was the Cummins weight was given as 612 kg, and we verified this with them. The actual weight was 840kg with ZF box which is 72 kg. This makes their advertised weight about 20% out.
Engines of this power to weight ratio will nearly always be used in performance boats where weight is definitely an issue. In fact we would not have bought the Cummins if the correct weight had been advertised.
But in saying all that it is still a nice engine.
Our rule now is, check the weight before fitting it. They DO fib.

Jack.

[hoytedow]

No Yamaha's lower end brand is Selva. Tohatsu's are built by Nissan. I don't know if they are 1:1 the same though.




Actually, Tohatsu builds engines for Nissan.

[Wynand N]

So Wynand, what will it take to actually get the info I requested from you :rolleyes: - I was under the impression you are a dealer :confused:

Fanie, I will do better and phone you with the info. I was so busy meeting deadlines with boat repairs/buoyancy now that summer is here again and guys wanting to get on the water, I forgot your stuff....

Anything with a 15 hp motor here has to be surveyed, yearly :( It just about making money and nothing else.

Actually Fanie, according to SAMSA Marine Notice 13 (latest) any engine size up to and including 15hp, are excluded from all the crap (skippers license, COF, COL) but the hull, if over 3.1 meters, must still have buoyancy fitted and the boat must carry the basic safety equipment as required in Category "R" boats.
Anything over 15hp, even a 15.5hp, you are in for the full monty so to speak;)

[Wynand N]

The point is that many people always assume that 4 strokes are much heavier than 2 strokes. I only point out that this is not always so.

Im with Watson on this - I still have to see a 4S of similar hp that is lighter than a 2S version....

Detuned engines are generally considered to be more reliable and rugged than their more optimized competitors.

This is true - having all the Tohatsu info at hand, I can safely say that the following engines are sisters of same cylinder capacity and tuned and de-tuned to their specific ratings. Usually the lower rated engine achieved its HP at lower RPM and some carb jetting, timing and port tuning are the main differences. The numbers below are for two stroke only.

4hp & 5hp - single cylinder - 102cc
6hp, 8hp & 9.8hp - twin cylinder - 169cc
9.9hp & 15hp - twin cylinder - 247cc
25hp & 30hp - twin cylinder - 429cc
40hp & 50hp - three cylinder - 697cc
60hp & 70hp - three cylinder - 938cc
115hp, 120hp & 140hp - four cylinders - 1768cc

[tom28571]

[QUOTE=Wynand N;302449]Im with Watson on this - I still have to see a 4S of similar hp that is lighter than a 2S version....

A matter of reading the words. The statement was "much" heavier, not "lighter" than 4 strokes.

[rwatson]

the following engines are sisters of same cylinder capacity and tuned and de-tuned to their specific ratings. Usually the lower rated engine achieved its HP at lower RPM and some carb jetting, timing and port tuning are the main differences.

Hi Wynand

You would have to provide the RPM/HP curve graph to convince me though.

Especially with two strokes. A cheaper, nastier exhaust will drop the HP significantly.

Actually, I dont see the 60 HP 2 stroke on sale
say at http://www.tohatsu.com.au/products.htm

are you sure they are still current ? - the 140 HP 2 stroke you quoted before is N/a

[Wynand N]

Actually, I dont see the 60 HP 2 stroke on sale
say at http://www.tohatsu.com.au/products.htm

are you sure they are still current ? - the 140 HP 2 stroke you quoted before is N/a

Watson, seems like different markets dictates different engines. Here in the land of murder, rape, corrupt government/president etc, we have no laws re emissions to adhere to, and we still have have a ball.;)

The Tohatsu 60hp is available from our importer and in stock. The 140hp is a hot number here and freely available - how many do you want to order from me?:D

As soon as I have time available, I will post you the rpm of the "sister" engines mentioned later.

[mwatts]

Wrong on both counts;) Perhaps as a Tohatsu dealer I can shed some light on these magnificent motors...

Tohatsu is build by Tohatsu who incidentally is the biggest and oldest outboard engine manufacturer in Japan. In some markets the Tohatsu is marketed as a Nissan and this may come as a shocker to those believing in the American dream. All Mercury's two stroke engines from 50hp down to 2.5 are built by Tohatsu and are just badge engineering. Mercury's four stroke are build by Tohatsu.

Ok thanks. Good to know.

What is Selva then?

[rwatson]

Watson, seems like different markets dictates different engines. Here in the land of murder, rape, corrupt government/president etc, we have no laws re emissions to adhere to, and we still have have a ball.;)

The Tohatsu 60hp is available from our importer and in stock. The 140hp is a hot number here and freely available - how many do you want to order from me?:D

As soon as I have time available, I will post you the rpm of the "sister" engines mentioned later.

Thanks - some indicative pricing would also be welcome. Why would anyone buy the 60 hp for example ?

[Fanie]

Why would anyone buy the 60 hp for example ?
Because it's the closest to a decent motor you can afford :D

Lets face it, outboards have become really expensive.

[rwatson]

why would the 60 be much cheaper than the 70 when they are basically the same motor ?

Probably why they arnnt on the range in Australia

Thats why I asked for prices.

[Wynand N]

why would the 60 be much cheaper than the 70 when they are basically the same motor ?

The 60hp Tohatsu is not on our importers list anymore after checking yesterday and wont be imported again. The 50hp & 70hp units are and the price difference here are also small, although they are different motors. My retail prices for them are as follows in ZAR.

50hp = ZAR47500
70hp = ZAR53750

The difference is about Aussie$ 960

[rwatson]

The Tohatsu 60hp is available from our importer and in stock. The 140hp is a hot number here and freely available - how many do you want to order from me?:D.

Bugger - I had the cheque in my hand ready to post. I bet the 140 2s is unavailable to.

Its as I thought - the 60 was the same motor - and a waste of catalogue space.

A thousand dollars is about the right price difference between models.

As BOAT = "Bring Over Another Thousand"

[Wynand N]

told you before the 140 2s is a hot number here...I have stock and the importers have ample. The reason for this engine selling like hot cakes is the fact that is cheap and a lot of bang for money. Its direct competitor is the Yamaha 130hp and 150hp that sells for 40% and 58% more respectively here locally and the Tohatsu has all the Yam features and more - possibly the better engine as well.
That said, some engines in this brand are hard to get by due to world demand and to name but two - 2,5hp and the 25hp 2s are rare - my importers can only have an assignment of these coming in February due to factory production deliveries:(

[powerabout]

Could you add the BRP engines as they are all 2 strokes from 25 and up.
I would be interested to see how much lighter they are?
Thanks

[rwatson]

Never heard of BRP.

Have they got a web site with specs ?

OK, You mean Bombadier Recreational Products - for out boards that = Evinrude, I have heard of them

I hope their motors are better than their web-sites, nothing works. If you dig out the weight, model and HP from somewhere, I ma happy to stick it on the graph

[powerabout]

Works for me I used the Ozzy one
http://www.evinrude.com/en-AU/
you need to load a pdf for each engine
here's one 60hp = 109kg 20" tnt
You might want to add cc and cylinders to help correct the data as one manufacturere might be at the hp top end of an engine range while another may have the largest cc and kg as it is the bottom end of the model design range.
You also need to look at prop diameter and gear ratio to also compare what will happen in the real world between 2 engines of the same horsepower.
So one will make a light boat go fast and the other will pull more skiers out.
Comparing horsepower of outboards is not as good a measure than if you were talking diesels etc due to the above especially in the mid range.
Unfortunately its the only real measure you have as a consumer.

Nice work
Regards

[fastpowerboats]

AeroMarine has a database of all outboard and inboard engine specifications (http://www.aeromarineresearch.com/motordesignwizard.html), I think it includes all specs including weights, HP, RPM, etc. for entire HP range by each manufacturer.

[rwatson]

Thats facnastic !. It costs $70, but its well worth it if you have Outboard selection to do

Good tip FastPower

http://www.aeromarineresearch.com/cgi-local/SoftCart.15.exe/online-store/scstore/p-004.html?E+scstore

[fastpowerboats]

PropWorks2 at new link (http://www.aeromarineresearch.com/prop2.html)

[Wayne Grabow]

I am currently shopping for an outboard in the 40-60 hp range and have collected some figures from manufacturers sites. Suzuki has a new 60 hp, 941 cc, which weighs 229 lb., about 104 kg. That is lighter than many competitors 60 hp models including the 2 cycle Evinrude.

Right now I am favoring buying the 40 hp Mercury 4s, but am still looking. I appreciate this topic and discussion.

[Easy Rider]

Wayne,
Just looked at the new Suzuki. It is indeed completely new. I have the old DF60 .. 1300cc and much heaver. It's a magic engine but I'm sure the new one is better in many ways. I remember the 4 valve motorcycles were smoother and had a much wider power band. The same engine had more low end AND high end power. Engines keep getting better, more expensive and more complicated. Have you looked at the Tohatsu/Nissan LPDI 3cyl 2 strokes?

Easy Rider

[Wayne Grabow]

"Engines keep getting better, more expensive and more complicated. Have you looked at the Tohatsu/Nissan LPDI 3cyl 2 strokes?"

The specs of the Nissan 50 hp, 3cyl. 697 cc @206 lbs (94 kg.) appear excellent. I have it on my list to investigate further. However, here in Colorado, boating supply sources are sparse. I haven't been to the Nissan dealer yet; it is a little further away. I also have been told by several mechanics & dealers that in this area I should stick with Mercury or Evinrude because sources for parts and service for the others are so limited.

A somewhat unique part of my learning and decision in this quest is that here in Colorado we have some beautiful lakes located at 9000+ foot altitude. The appropriate engine for a boat located on the coast may be too weak here. As I understand it, it takes about one hp per 50 pounds displ. to plane a hull, and an engine looses about 2% efficiency for every 1000 ft gain in altitude. As you say, engines are expensive, and I need to get a somewhat larger one for the approx. 1500 pounds at full load for the hull I am building or risk not getting "over the hump".

[Easy Rider]

Wayne,
It sounds like hp per lb would be a big issue at that altitude. Any engine you buy should be fully able to compensate for the different fuel mixture (leaner) that you will require. I wonder if outboards come w the mixture excessively lean to minimize emissions or if the fuel mixture is optimum for performance? Early carberated cars had lots of problems and fuel injection seemed to solve the driveability issues but I've wondered since if the mixture is now perfect for performance or is it a compromise. I suspect the latter as I remember the old cars as being snappier but at 70 my memory may not be snappy either and I'm aware there are lots of other variables as well.

Easy Rider

[Wayne Grabow]

Fuel injection really helps keep the engine running efficiently, and all the outboards I am considering have injection. You are correct that weight, of the entire loaded boat, will be critical. Since this boat is a semi-planing hull of my own design, I have to do some estimating of the constructed hull weight and of expected and desired performance. But, of course, that is what I signed up for in starting this project. I was originally thinking 30 hp but got what I think is good advice to use more power with a larger prop.

[Easy Rider]

Wayne,
You will need a light boat. Can you easily tell me about the boat?

Easy Rider

[Marco1]

Is there a reson no one talks about Honda?
I thought they are very good motors particularly quite and trouble free.

[Easy Rider]

I looked at Honda when I bought my 60 Suzuki and at that time the Honda was carbureted. The Suzuki and all others had injection. The big issues I had w Honda was the prices and the small propellers. However a good friend of mine has a 20hp Honda on a 14' Lund and it performs well But lower gear ratio's and bigger props are always better at low to med-high speeds. I think small props are found on many outboards as a design compromise. They are much less sensitive to pitch and diameter. Small outboards are clamped onto boats w extreme variations in size, load and speed. It's hard to over speed or over load an outboard with a small high speed propeller. I feel I'm skillful enough and knowledgeable enough to run a big prop w low gears. Now that I have the very complicated Suzuki w fuel injection here in Alaska I may be better off W carburetors. The Honda's are by far the best looking of all the engines. And ther'e not black. When I got the E-tech for my 16' skiff I was looking for more simplicity and again the biggest prop.

Easy Rider

[Wayne Grabow]

Wayne,
You will need a light boat. Can you easily tell me about the boat?

Easy Rider

developable-surface-boat-designs.blogspot.com will show you more than you want to know. At this point I have sheathed the hull in 6 oz. cloth and epoxy resin and am sanding and filling to get it smooth. It will be an 18' x 5'8" runabout hull.

A 50 hp Honda is $1500 more than an equivalent 50 hp Mercury. A 40 hp Yamaha is $1000 more than a 40 hp Mercury, and this engine was jointly developed by the two companies (same weight, disp., and hp). That is why I doubt if I will end up with a Honda or Yamaha. The 40 hp Merc, 50 hp Nissan and 60hp Suzuki are what I am presently considering. Haven't got a price on the Nissan or Suzuki yet, but there's plenty of work to do before I need to make a final decision.

[gonzo]

Nissans are Tohatsu painted grey with a slightly higher price.

[pfridays]

The new 2010 Suzuki 60 weighs less than their 40 & 50 !!!! It's great...The old 60 was heavy .

[Wayne Grabow]

Today I finally talked with the local Nissan/Tohatsu dealer (70 miles away). He said that their TDLI two-stroke engines have had problems at the mountain lake altitudes (about 9000 feet) but that the problem has just now been fixed. New stock will have a revised control to handle the altitude, and a repair kit for older engines will be available soon. 50 hp in a 206 pound engine is very attractive; I will be investigating this further.

[marshmat]

Mercury certainly seems to be the dominant brand in many of my cruising areas. I think this is more for historical reasons- it's always been that way, so the service/dealer network is there- than for any current technical reason. Johnson/Evinrude from the OMC days are also very popular; the things just don't die and parts are still readily available. Yamaha and Honda are occasionally seen in these parts; Suzuki, Tohatsu, Nissan are quite rare.

There's a new brand called APS that I've seen a few examples of- they're sold through Canadian Tire, $2000 for 9.9hp and the owner reports, so far, don't seem particularly good.... I haven't seen one dismantled yet, but they look an awful lot like a Chinese clone of an older Merc four-stroke.

I'm with Easy Rider on the props issue- let's see some steeper gear reductions and larger diameter props on these things. The stock small gearcases are fine for a little aluminum fishing skiff, but it'd be really great if more manufacturers would start offering optional, larger lower units with 2.5 or 3 to 1 reduction and the ability to swing, say, an 18" prop on 50-60 hp. Only a couple of them are doing this right now- there's a reason why so many pontoons and working boats run Merc or Yamaha. Evinrude's latest are getting better, with 2.67:1 ratios as standard on many models....

Oh, and what the !@#$ happened to outboard prices lately? A 60 hp Honda is $7500, a 60 hp Yamaha is a hair over $9000.... only a few hundred bucks short of a new Kia Rio sedan and more than the average student pays in rent for a year.

[powerabout]

Marshmat
The problem with putting a large gearbox on a smal engine ( and yes it would be great) is that the thrust it can create and more of a problem is in reverse is that the load is more than the transom bracket/swivel tube can handle.
This has happened to manufacturers before when they have made high thrust engines and you break things that you normaly couldnt.

A manual tilt engine will need a massive reverse lock so if you then impact somethng in forward..its going to be ugly depending how thats configured.
You also have the problem to ensure the engine can produce enough power at idle so when it goes into gear it wont stop

Depending on the model some smaller engines do use the the larger horsepower brackets so they could do it but its not as straight forward as one would think.
Not to mention just about all outboards and the accessories are designed for bass boats