which 9.9 engines can be converted to a 15?

Hey guys,
I did a search but could not find what I was looking for. Are there any sites/links that show which older engines can be upgraded either by changing the carbs or removing the "pin" that converts at 9.9 into a 15? Thanks.

So you want to go from a 15hp down to a 9.9? It is usually the other way around. All I know is OMC's and I know 1974-1992 can be converted up or down

So you want to go from a 15hp down to a 9.9?

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Maybe you should read his post

which older engines can be upgraded

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that converts a 9.9 into a 15?

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:lol:

I had converted my 1974 Johnson 9.9 EL to a 15 with just a carb. swap. Some motors need shims put in and such, but the easiest is just find one that needs a carb. only.

I do know the older Nissan 9.9 motors will be a 15 with just a swap of the throttle restriction plate. I know that one for a fact as 2 of my friends have them..

crazymanme2 said:

So you want to go from a 15hp down to a 9.9?

Click to expand...

Maybe you should read his post

which older engines can be upgraded

Click to expand...

that converts a 9.9 into a 15?

Click to expand...

:lol:

Click to expand...

Maybe you should look at the time of Johny's post and the time of the op's edit

Last edited by aaronjbrowning on 25 Sep 2012, 22:04, edited 1 time in total.

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#-o

:lol: =D> :lol: Thanks MOE I owe you one

anyone have a list of which motors will work?

aaronjbrowning said:

anyone have a list of which motors will work?

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Johny25 said:

So you want to go from a 15hp down to a 9.9? It is usually the other way around. All I know is OMC's and I know 1974-1992 can be converted up or down

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That means any Johnson/Evinrude from those years, and someone also mentioned older Nissan's. Your question is pretty vague and open ended so I am not sure what you are expecting? Do you have a motor you are wanting to do this to? If not then before you purchase a motor ask us or do your own research and find out if it can be converted.

Thoughts on this one being converted? Owner said it's a 1987.
https://annapolis.craigslist.org/boa/3292449246.html

Mercury did not make a 15hp in 87' so no it cannot be converted into a 15. And I would be very suspect of someone claiming 21mph with a 9.9 on a 17' boat of any kind :lol:

thanks for the info! back to the search

Find a 15 and change the sticker plate to indicate its a 9.9 model.

https://washingtondc.craigslist.org/nva/boa/3304742708.html

Like this?

nevermind...long shaft wont work.

Is that why you are looking for a 9.9 that can be made into a 15, so you can run lakes that have restricted HP on them? What size boat are you putting this on anyway?

14ft

thoughts on this one?
https://annapolis.craigslist.org/bod/3304925316.html

Yep that can be converted to a 15hp. I have the exact motor and I converted it to a 15hp. You need to get the 15hp carb and 15hp exhaust horn is all. Have to pull the power head to switch the exhaust horn though.

excellent. thanks for the info. what do you think about the price he is asking? Any complaints on the motor itself?

Motor looks to be in fair/good condition. I would ask why the thermostat and head bolts have been removed, as I can see they are all missing the factory paint in the pics. Sure sign the head has been pulled before. Do a compression test before buying. You want a minimum of 100psi in each cylinder with no more than 10-15% difference between the two. All that being said the motor is not priced cheap but it is not outrageous either (as long as it has good compression). My motor which was purchased new in 87' by my father and handed down to me is in great condition and has been maintained and stored inside its whole life, and if I were to sell it I couldn't reasonably expect more than $800-900. I still have yet to see an 87' for sale in the condition mine is in though.

As far as the quality of the motor.....second to none in that HP range. These were OMC's best years and that motor is bullet proof if maintained well. I have no complaints in the 25yrs we have owned it.