2010 9.9/15hp yamaha difference

[boater1234]

I have a 15hp 2stroke merc at 262cc's and it runs on a 50:1 oil ratio.Well i was thinking if i went with a 9.9 2stroke yamaha that runs on 100:1 i would use way less oil and save a load of money.Here is what my question is,i have had 9.8 tohatsu 2stroke in the past and it was like 159 or 169cc's and had really good get up and go.I have looked at the 9.9 yamaha 2stroke that a marina has down the road from me for $2000.They have one 2stroke left and that will be it as they stopped making them as most people know.My question is will that 9.9 have more top end and power because it has 246cc's and is based off the 15hp 2stroke powerhead compared to the 9.8 tohatsu with 159cc's.I was talking to the guy at the marina and i asked him if i bought the 9.9 will you convert it over to the 15 for me and he told me yes if you want but it would be a waste of time as you won't see that much of a performance difference for what it will cost me,is this true?

I have been throwing around maybe even going with a new 20hp 4stroke but if this little 9.9 2stroke yamaha will getter done then i will sell my 15hp 2stroke merc and just get the 9.9 if there is very little difference.I have been throwing around all kinds of outboards and what would be the best fit for me and my family.

He told me it was the carb and reeds that was different from the 9.9 to the 15yamaha 2stroke.I was just throwing around the idea as i spotted it a few days ago and was thinking about it.The biggest reason is i would be able to do 100:1 instead of 50:1 and that will equal a whole lot of oil savings and i will get a 2yr warranty.I want a motor that has never been started so i know what has been put in it and how it was fully maintained by me.Is there a big difference in the 9.9 and 15 yamaha or is it a waste of time.I'm so darn confused about what i want.I would like to have a brand new 15hp merc or yamaha 2stroke but they are gone and the yamahas i find are insane as far as price.

 

[boater1234]

Re: 2010 9.9/15hp yamaha difference

No help on this one i guess.

 

[99yam40]

Re: 2010 9.9/15hp yamaha difference

My thoughts on this are, how much oil do you use in a year running through your 15 Mec right now?
How much does that cost you @year?
Divide that by 2 and that is all you will be saving per year and you have to spend how much $$ to save how much $$. Just does not make a lot of sense to me if that is all you are looking at.

 

[boater1234]

Re: 2010 9.9/15hp yamaha difference

I just want to know what the performance difference will be from the 15hp 2stroke merc to a 9.9 yamaha 2stroke.If it's marginal then i will go get a brand new motor out of the box and sell the 15hp 2stroke.If it's going to be a big performance difference then i will stay with the merc.The guy at the marina told me the difference between the yamaha 9.9 and 15 is very marginal.I asked him if i were to buy it would he make it into a 15hp yamaha for me and he said it would not be worth it as i won't gain much speed or power.I want a new 15hp yamaha but they are getting so expensive by the day as you can't touch them for less then $3000 as they stopped making them in 09 and whatever is left over they are charging out the ying yang for them.So i found this 9.9 for $2000 which is the last 2stroke they have and i was curious to see what was involved in converting it into a 15hp and he told me don't waste your time.I have a 14ft alumacraft that has the 42"floor and a 63" beam and weighs in at 230 lbs.From what i hear the 15 will shoot it like a rocket ship but i would like to have a brand new motor that has never been used but by me so i know what goes in it and how it is serviced.I had a 9.8 tohatsu yrs ago and it was 169cc's and was on a 12ft jon boat and did well but the yamaha is at 246cc's will that make a difference in top end?Will that push that boat well?I know jon boats are easy to move and i don't need to be a speed demon but a little top end speed would be nice.

 

[JB]

Re: 2010 9.9/15hp yamaha difference

Actual difference in WOT will depend on many factors in addition to the outboard displacement. It is impossible to predict.

It is logical that 246cc will make more torque than 196cc, ALL OTHER THINGS BEING EQUAL, but making all other things equal is not likely, and that is not likely to produce noticable differences.

 

[99yam40]

Re: 2010 9.9/15hp yamaha difference

HP is HP and all the motors now are rated at the prop I believe.
So a 9.9 is less than a 15 and you need to look at the size and pitch of the props they are turning along with the gear ratios, you also would need to see what WOT RPM the different motors are rated at.
If you have a well running 15, I do not think a 9.9 would have as much to it and you have to run it harder to do the same load and speed

 

[boater1234]

Re: 2010 9.9/15hp yamaha difference

Ok i will stay with the 15 merc thanks guys.