Convert 4-stroke Merc F8 to F9.9 ?

[BVP]

Hi guys,
I would need just a little more power on my small boat and I am curious if it would be possible to upgrade my 8 hp to a 9.9 hp. It's from 2007 and according to the brochure these engines share many specs, like for for example:
same volume
same weight
same looks
same controls
same gear ratio

That makes me think they are more or less the same, and that the difference lies in the fuel system. Does anyone know? I got it second hand for a good price, so I'd be prepared to pay for parts if needed.

 

[bob1340]

Re: Convert 4-stroke Merc F8 to F9.9 ?

Go to an online parts list and compare numbers. Being it's a four stroke look at the following:
carb
cam
cylinder head
piston

probably the same bore and stroke but one or more of the above componants can be different. Also look at the prop pitch between the two.
The only difference I can see between my '70 7.5 hp and a 9.8 hp is the carb. It's a two stroke though. I doubt the piston or head on yours will be different, but the carb and cam may be.

 

[BVP]

Re: Convert 4-stroke Merc F8 to F9.9 ?

Thank you, I'll do that! Could you recommend a good online parts list? I have googled some, but haven't found one that is complete yet. Thanks in advance!

 

[bob1340]

Re: Convert 4-stroke Merc F8 to F9.9 ?

Thank you, I'll do that! Could you recommend a good online parts list? I have googled some, but haven't found one that is complete yet. Thanks in advance!

Look here on iboats and the link I sent.

 

[BVP]

Re: Convert 4-stroke Merc F8 to F9.9 ?

Look here on iboats and the link I sent.

Thanks!