Merc 9.9 to 15 Horse Power

Nightfisher · 25 August 2015, 06:33

Hi guys,

FYI: After studying the rumour for a few months that it can be done, it can.
Non four stroke 1996-2003 9.9 and 15 HP Mercury (Tohatsu designed/built) engines are the same with a couple of differences.

One: carburetion; Two: exhaust baffle. Possibly Prop pitch and Plug type.
Ordered the 15HP carb, The external carb Body is exactly the same, inside the throat is much-much bigger as are the venture. The exhaust tube ID is reported to be only 1/8th inch bigger so will not change it. Will lose "1/4-1/2 HP" not changing the tube which saves pulling the engine apart.

Don't need speed, just more power out of the hole-shot for faster plane since carrying two batteries, one a 31 series 108 lbs. What I like most is no increased engine weight.

dave3235 · 25 August 2015, 11:16

Quote:

Originally Posted by Nightfisher

Hi guys,

FYI: After studying the rumour for a few months that it can be done, it can.
Non four stroke 1996-2003 9.9 and 15 HP Mercury (Tohatsu designed/built) engines are the same with a couple of differences.

One: carburetion; Two: exhaust baffle. Possibly Prop pitch and Plug type.
Ordered the 15HP carb, The external carb Body is exactly the same, inside the throat is much-much bigger as are the venture. The exhaust tube ID is reported to be only 1/8th inch bigger so will not change it. Will lose "1/4-1/2 HP" not changing the tube which saves pulling the engine apart.

Don't need speed, just more power out of the hole-shot for faster plane since carrying two batteries, one a 31 series 108 lbs. What I like most is no increased engine weight.

Hi

Did you order new or second hand,also where did you order it from looking at at derestricting my 20hp which is also a carb change.

Nightfisher · 27 August 2015, 20:15

Couldn't find a second hand 15, 2003 Merc Carb. But merc still makes them new and most suppliers (Canada/USA) carry them or can order but are they ever expensive. So, since I live in Canada and don't needed the additions of import duties, exchange rate, taxes and freight I have ordered from a close Mercury supplier. Still, over 300.00 Cdn Dollars.