Minimum horsepower question

gotboostedvr6

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I just bought a Bayliner 17 foot Capri 1998 with a blown motor. I'm planning on installing a properly running and freshly tuned up 50 horse Yamaha 4 stroke. I also plan on using a 17 pitch 4 blade stainless propeller.

I only plan on using it for cruising and fishing purposes. It does not have to be fast or ever pull a tube tube or skier.

My question is do you think the boat plane with a 50 horse motor?

My guess is that the hull weights is somewhere between 1185 and 1250 pounds.

Thanks
 

JoshOnt

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I am going to guess it wouldn't, likely had a 115 on it before. I would say go no smaller than a 70.
 

64osby

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Dry weight is listed as 1475, max hp as 85.

Many say the minimum should be 75% of max or for you a 65hp motor.

IMO the 50 Yammy will be fine if you are not trying to do water sports. It may be slow to plane. You may need to adjust some weight forward.
 

smokeonthewater

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My bet is that if you can get the right prop on it then yes it will as long a you are loaded light. My guess is top speed 22 mph.

Don't know what ratio you have but I think 17" pitch is too much.
 

smokeonthewater

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May need some smart tabs too.. Also put as much weight forward as possible such as batts, anchor etc.
 

littlerayray

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You will probably be running that 50hp outboard at wot to near wot to stay up on plane imo
 

Sea Rider

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85 HP is stated for max number of passengers, if boating with much less no need a 85 HP engine. with a underpowered 50 HP engine it's a matter of siting engine at correct transom height, well trimmed and with weight evenly distributed on deck. Can maximize prop for engine to run at near max wot rpm range, full throttle to plane faster and once on plane back up to maintain good plane, speed and better fuel consumption.

Once engine is installed along prop, go for 2 wot spins on flat calm water cond that's lightly loaded and family oriented and check both achieved wot rpm to know if inside safe working engine range. That selected prop probably won't dial what you want, but it's a good reference going from dialing best prop for that application.

Happy Boating

.
 
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steelespike

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Your 17" prop is way too much I think a 12" pitch is a good starting point.
It is critical the motor is able to operate within its rated rpm at wot.
If it planes with the 17 it won't make rpm and will perform very poorly
Once propped right you can operate at what ever rpm suits you .
 

gotboostedvr6

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Got her running today. Motor tucked in it planes at 16 mph. Maintains plane tucked at 13.5 mph.

Max speed trimmed out 27 mph. Bow rides very low at speed. No tach but rpm seems low.
 

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Frank Acampora

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Fishing--OK as long as you don't mind a long ride to get there. Cruising--depends upon your definition of cruising. Out on the bays or rivers with a destination, where you need to cover distance, no go. If you just want to putter around as a Sunday ride--OK.
 

fishin98

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I had a 2000 1802 Capri Cuddy with a 2000 90hp Carbed Merc. 19p 3 blade prop with a 4 blade 17p spare It was a perfect set up, fast and easy on fuel. The optional motor was a125 Merc. With the 50 your going to be a bit light on HP, now your running a 17p 4blade on that Yammi, which I'm sure is speed prop for that motor, to get the most out of that setup look to step down to a 15 or even a 13p. Is that indicated speed by GPS or by the boats speedo. To get a Ideal cruise speed your setup needs to maintain a proper cruise speed at 3/4 throttle. Be careful not to over speed the engine. In my opinion get rid of the 17p 4 blade, step down to a 13p-15p 3 blade you will get better performance. Just my 2cts!
 

gm280

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Personally I like to put as big an engine as the hull was designed for, and here is my reason for that. The max HP for the boat is the better choice because you can make the boat go fast if you have too like in an emergency or get caught up in a bad storm coming your way.. And years down the road when the engine gets tired, and it will, you still have enough power to use it yet. And you can always throttle back, but you can't make it go faster if there is no HP to do so... JMHO!
 

smokeonthewater

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Nothing in the world wrong with 27 mph if you're happy with it! I've had boats that wouldn't go that fast that I loved.... Forget the naysayers n have fun.

Absolutely get a tach on it and get the right prop... You don't want to be lugging the engine.

If you wanna go cheap search for "tiny tach" on ebay.
 

roffey

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I agree with smoke. I cruise at about 25 mph for the most part
 

gotboostedvr6

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The dash has a complete set of maxum merc gauges.

I gotta figure out how to run those gauges to the Yamaha.
 

gotboostedvr6

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Tiny tach on the way.

Actual prop pitch is between 12.6 and 11.185" depending on where you measure.
 
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