motor size?

[MD746]

Im in the process of restoring my boat and have decided to look for tiller steer motor . I want a yamaha just dont know what is a good hp fit for the boat the capacity plat is unreadable. its 15' long 48" wide

 

[Home Cookin']

Re: motor size?

Depends on your skills and intended use, and who will be driving: A 15 would be best IMO. 20-25 is getting a little fast for many boaters and for the children if you let them take it out or learn on it; that may even be above the manufacturer's capacity. Don't go above 25. The popular 9.X will do fine. A 6 is OK for putting around if you are going to use it as a dinghy or in ponds, but an underpowered motor is dangerous if you may find yourself confronted with current, wind/waves, heavy load and cold--i.e. duck hunting.

 

[mpsyamaha]

Re: motor size?

i agree... somewhere between a 15-25hp should be good. depends on what kinda weight and what youre using it for.

 

[Willyclay]

Re: motor size?

The link below is the USCG regs for boat manufacturers' calculation of maximum horsepower capacity, Section 183.53. The formula, calculated in feet, produces a Power Factor (LxW) of 60 for your boat. Using the table for boats with PF's over 52.5, no remote steering and a transom height less than 20 inches, you are limited to 15HP for flat-bottoms or 25HP for all other hulls. I cannot determine your hull design from the picture. If you change any of the criteria such as additional fractions of feet for the length and width or add remote steering and increase the transom height like some forum members have done, the maximum horsepower capacity will increase. Good luck!

http://edocket.access.gpo.gov/cfr_2004/julqtr/pdf/33cfr183.53.pdf

 

[ezmobee]

Re: motor size?

I certainly wouldn't limit myself to Yamaha. They make great motors but it's tough to go wrong with a motor from any of the major manufacturers. Are you looking new or used? If new, have you priced them lately? Crazy expensive. You many find that a nice 80's of 90's JohhnyRude will fit the bill quite nicely

 

[MD746]

Re: motor size?

Thanks guys for the advice I was leaning toward the yamaha due to the fact the locally dealer had some 09 models he is wanting to move I had my eye on the 20hp just wasnt sure until now , I think Im going with the 20hp and I will shop around on diff. brands.

 

[JimS123]

Re: motor size?

Too many unanswered questions here. First of all, you need to find out what the capacity plate says. Not only for safety reasons, but legal liability as well. You should not overpower the boat. Contact the manufacturer. If the boat is real old and they are not in business, google the ACBS or Fiberglassics or other sources to find out old specs.

A 48" beam sounds awful small for a 15' boat. A 20 hp may be too big.

I am assuming that a 20 Yami is a 4-stroke. Thats a pretty heavy motor. That in itself may be too much weight for the old transom.

Looking at your picture, it looks like that's a short shaft transom. Better check that out too. Yami does make a 15" 20 HP, but they are few and far between. Most dealers stock only long shafts.

Two years ago I upgraded from a 15 to a Yami 25 (2-stroke) on my 14' aluminum boat with a 67" beam. It was wayyyyy too much power and I ended up upgrading the boat next....LOL.

 

[Home Cookin']

Re: motor size?

Agreed. I put a 25 on a 14' Lowe wide body jon boat and while I (safety-minded and often sober adult) could handle it, it was way too hot for all the children and child-like adults who were using it (at a hunt/fish club) so we backed down to a 15.

 

[MD746]

Re: motor size?

The capacity plate it unreadable I have searched for the info with no luck, I did find out the two lakes that we will be fishing only allows a max hp 9.9 so for safety since I can't find the capacity info Im going with 9.9 2 stroke I dont need speed just a reliable safe setup.

 

[MD746]

Re: motor size?

this is the only pics I can find of one with the original setup I do know its a 71 model. Just not sure of the motor size on this boat.

 

[JimS123]

Re: motor size?

That pic with the car in the background gives a better perspective of the size of the boat. I think you'll be very happy with the performance of the 9.9. It should plane the boat as long as you get the right prop.

 

[ezmobee]

Re: motor size?

^^^ I agree. Get a 9.9 or a 15. The 15s are usually the same weight from most manufacturers.