9.9 to 15 upgrade

[grayghost]

I'm currently running a '93 Johnson 9.9 on a 14' aluminum fishing boat. I've been concidering upgrading the carberator to a 15 for a few years now. The dealer wants about $300 to install and setup a new carb.<br /><br />Does this sound like it's worth it? Should I buy the carb and install myself (any trick in setting them up)?<br /><br />Thanks

 

[dmessy]

Re: 9.9 to 15 upgrade

Well, you have a 10 year old motor that is worth around 5-6 hundred, do you really want to spend 1/2 its worth on an upgrade to get a little more power and more fuel usage? Probably not...<br />You can install a bigger carb yourself but you'd need to rejet it and do a plug read. <br />If it where mine, I'd leave it status quo

 

[JB]

Re: 9.9 to 15 upgrade

Howdy, GrayGhost.<br /><br />We get this question several times a year.<br /><br />The "15" carb will fit and it will increase power, but not enough to notice without very sensitive instruments.<br /><br />The two engines are the same displacement, so torque at a given rpm will differ only slightly. The 15 is rated at a higher RPM and it reaches that higher RPM only partly because of the carb.<br /><br />Bottom line? It would be cheaper to buy a used 15 and switch the bonnets if needed to use on "10HP" lakes.<br /><br />Good luck.

 

[Bear]

Re: 9.9 to 15 upgrade

New carbs $195 or $212 <br /> The difference 1974 – 1992, yes 1992 - scroll down to Carburetor <br /><br />14' boat and 9.9 hp, yes 5 hp more will make a differce if it is slightly under powered sometimes. <br /><br />I have a 12' and tried my old 6 hp Johnson on it. It had not enough power. I bought a 8 hp Mercury and it flies.