Mercruiser 130 Hp + Overgeared Alpha One

[henrik_cla]

I recently bought a used boat "Funliner Fantastic 195", a daycruiser simmilar to "Bayliner 1950" and I have a problem with it, on full throttle my rpm doesn't go over 3100. Current top-speed of the boat is ~26 knots.<br /><br />Engines is Mercruiser 3.0 Liter 130 HP (1988 or 1990, I think) with Alpha One. I think my gear-ratio is 1.6:1 and propp is 19" pitch.<br /><br />This engine and drive used to be in an boat with 160 HP.<br /><br />Is there anyway I can find out the gear-ratio, without taking it apart and count ?<br /><br />Can I compensate the low rpm by switching to a smaller pitch on my propp (15"), or is anything else wrong ??

 

[Bob_VT]

Re: Mercruiser 130 Hp + Overgeared Alpha One

http://www.mercruiserparts.com/ is a good reference for drive parts.<br /><br />Maybe I am reading the post wrong but....was the "This engine and drive used to be in an boat with 160 HP." motor changed?<br /><br />Your WOT should be about 4200 RPM. There could be allot of factors hindering it from reaching that point. Yes changing a prop will increase RPM about 200 rpm/inch of pitch but I think there may be more to your troubles. <br /><br />If your gearing is wrong the mercruiser site will confirm your ratios.<br /><br />Bob

 

[henrik_cla]

Re: Mercruiser 130 Hp + Overgeared Alpha One

Sorry, my misstake, Alpha One and propp used to be on a boat with 160 hp engine. Not the engine.<br /><br />I'm living in Sweden so my English is sometimes strange

 

[Bondo]

Re: Mercruiser 130 Hp + Overgeared Alpha One

The 15" prop will get you close.... you should have the 2/1 gears....