What size motor will my John Boat hold?

[bobdpt]

I have a 1972 Sears John boat that does not have a sticker stating what size motor it is rated to handle. I bought it used with a 15 hp gamefisher/force engine. The engine needs replaced. I have the opertunity to buy a 25 HP Mercury 2 stroke with electric start but don't know if it will fit. The measurements of my boat is 16ft length, 18 in. high and 55in wide at top and 38 in. wide at bottom. Does any know if a 25 hp will work on this boat?

 

[ondarvr]

Re: What size motor will my John Boat hold?

There is normally a big jump in size and weight when you go from 15 to 25HP and with a narrow boat it will have even a bigger effect on the balance. I would stick with a 15 or smaller.

 

[steelespike]

Re: What size motor will my John Boat hold?

Go to the new boat sites and check out the jons in your size. pay close attention to the demensions it will tell you.

 

[deejaycee_2000]

Re: What size motor will my John Boat hold?

on a 16ft boat ... no problem ...

 

[michael-lagrange]

Re: What size motor will my John Boat hold?

That would be alot of motor for that boat!!

 

[chugger]

Re: What size motor will my John Boat hold?

Here's a URL that might help. http://www.uscg.mil/d8/mso/louisville/WebStuff/comdtpubp16761_3b.pdf Someone posted some information about this a little while back so you might find more or better information by doing a forum search.

 

[bassboy1]

Re: What size motor will my John Boat hold?

The boat, being a 16 footer, might be able to hold the 25. Some 16 footers are rated up to 30. Others are rated for 15. Even if it will fit, the 25 will be heavier which might not let it plane correctly and will change the balance on your trailer. Stick with a fifteen.

 

[05GlastronSX]

Re: What size motor will my John Boat hold?

my 16 foot fisher is rated to hold a 40 tiller and thats exactly what i have on it. WAY to much power. i cant even use all of the throttle, I have it up to 30 mph and im only at alittle more than half throttle...:/

 

[tashasdaddy]

Re: What size motor will my John Boat hold?

first i would look at the wieght of the 2 engines, and how the boats sits in the water with the present 15. is there enough freeboard to take the extra weight of the 25.

 

[cobra 3.0]

Re: What size motor will my John Boat hold?

Differing opinions...

If you plan on keeping the engine on and rarely carrying it about, the 25 will work fine. However, the 25 doesn't troll half as smooth as any 15 would and can be a bear to carry. It really depends on what you need the motor for.

I had an 18 Merc(same as the 25 in size) on a 14 ft aluminum. Very heavy, loud, and shakky engine compared to the 15 Evinrude I have now. You really had to pull on that starter rope to turn it over. The 15 starts with only an easy 6 inch pull on the rope. Again, it depends what's important to you.

 

[fishdog4449]

Re: What size motor will my John Boat hold?

I would stick with a 15 or even a 10/9.9.
The lighter motor will make the speed about the same, and John Boats aren't know for their stability, so I would be leery about putting more weight on there than you need.
My friend has a 15 foot fiberglass skiff with a 15 Rude two stroke, hits about 30 mph easy.