repowering a 170 striper with a Yamaha 130

[jsakat1]

I might repower later down the line the next coming months and a Yamaha 130 has been offered to me. I have an 87 Striper 17 feet. I have read that the max HP is 130. Does anyone know if the motor is too big for the boat? I have a 75 mercury from 85. The potential new motor is a 93. Any feedback would be appreciated. I have heard the 115 and 130 weigh the same.

[RickK]

My first inclination is that the motor will be too heavy and cause the stern to sit pretty low in the water causing even less freeboard back there.  BUT I'm only going by what my boat does with a 115. My 170 is too old to compare probably anything about the two boats. I'll let one of the guys with one of your vintage kick in on this.  I think Miquel, DRZDave and CUsnooking have one about the same year as yours.
BTW I don't think a 115 and a 130 are the same head - usually it's 90s and 115s that are the same.

[jsakat1]

Rick thanks for the help as always this forum is invaluable to a rookie like me. I have been able to soop up and enjoy my little striper thanks to the help I have received from you guys.

Part of the reason this is so enticing is that I am getting the motor pretty cheap with everything (controls, prop) and its a well maintained motor.

I was looking at Yamaha's website last night, and the 1998(oldest model they have an online manual for)  115 and 130 weigh the same (368 - 377 lbs). I am assuming they would weigh similar The 93 model I think is lighter. I don't know if that is in the range of what most 115 weigh.

I am trying to find the weight of my current motor 85 Mercury 75 HP 4 cylinder to see how much more it would be. Would anyone on the forum have that?

[RickK]

My 115 weighs about 320 so that's a big jump to 370ish.  
Maybe there is a way to help with the weight like foam filled bait wells on the back OR find a 70s straight 6 Merc 115 blown out to 150  :twisted:   (They're narrow and light.)

[jsakat1]

The weight for the 1993 130 is 357 lbs. Is that still too much? About 25- 30 lbs more than the 115 you have on yours Rick. Is that a big difference?

[RickK]

Hard to tell.  My 170 was designed for a 70hp or so and at that weight (which was still pretty heavy back then), the boat self-bailed at rest.  
Here is a 170 catalog circa 1971 although I'm thinking my boat is either earlier than this or this is a 72 (or later) because my hatches are different,  the rod holders are different and the console is ....  They say 85hp max on the year of this boat.
     

Mine had a 115ish merc on it when I bought her and it was still fairly light for a straight 6. (I say ish because the decals said 150 but they didn't make a 150 according to the ser#) I replaced that motor with a 110 Rude and she has not self-bailed since.  Yours is newer so I'm sure they have changed a bunch to have it handle a 130.  If you can find out the weight of the 75, I think you could simulate the weight addition by putting a sandbag or 2 - whatever weighs the additional lbs - on the motor cowling and see how she sits.