aluminum boat transom

letitroll707

Cadet
Joined
Nov 20, 2011
Messages
24
My brother has a 14 ft mirrocraft boat and with a 1982 johnson 25 hp on it we only use it in saltwater. We want to upgrade the motor to bigger horse power and need to know how to reinforce the transom to hold the motor. We are thinking about a late 70's 50 hp mercury. So 1st what is the biggest motor you can put on this boat and 2nd how to reinforce the transom to hold the biggest motor. Thank you ahead of time for everyone that helps.
 

haymon15

Seaman Apprentice
Joined
Apr 6, 2010
Messages
37
Pictures of what you are doing helps a lot. A 14 footer might to small to upgrade to a 50 hp. You can do a free photo bucket account to post pictures here. Copy the url link in your post and tap on it to make it show up in your post.
 

letitroll707

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Nov 20, 2011
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We havent started nothing yet but I will post pictures we have the 25 on there now with no problems and were givin 2 50 hp mercurys 1 with jet and its only 50 poinds heavier than the 25.
 

Woodonglass

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Dec 29, 2009
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It's best if you use the IMG Code



A 50 Hp is WAY to much motor for a 14ft Tin Fishing boat like yours. The weight is only one factor to consider. What is the length of the shaft? I'm betting the 50HP are long shafts and your boat appears to be a 15" transom. You'd have to raise the transom 5" to accomadate the 50hp motor as well. That in itself would change the dynamics of the boat in a big way. Overpowering a boat has major consequences if and when an accident occurs and insurance comes into play. You're at fault no matter what, just because your boat was overpowered!!! I'd think twice before I'd put that big motor on that small boat. But Hey I'm just an Old Dumb Okie, AND a Glasser to Boot!!!!:D
 

classiccat

"Captain" + Starmada Splash Of The Year 2020
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Dec 20, 2010
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Is there a hull plate with max hp rating? 14' mirrocraft from that era usually cap-out at 25Hp.

find yourself some 16' tin to carry one of those 50's :thumb:
 

64osby

Admiral
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Jul 28, 2009
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If your in a giving mood I'll take one of the extra Merc's.:D

Nice fishing boat, but 50 hp might be too much.
 

bonz_d

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Apr 22, 2008
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5,276
At the bottom of my signature you will see a 14' Lund listed. That boat with a side steering console is much heavier and heavier built hull than any 14' Mirro and it is only rated for a 35hp max. I will tell you from experience that that Lund with a 35hp and only one person on board at speed with a moderate chop on the water becomes unstable. I would advise against putting that 50hp on there even with a reinforced transom.

I'd suggest taking those 2 Mercs and getting them running well and then sell them to find a nice 35hp OMC or a 40hp 2 cylinder Merc.
 

dozerII

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Oct 25, 2009
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6,527
I agree with the others too much HP for the 14. If that is pressure treated wood you are using for your transom don't:eek: the copper that is used to help preserve the wood will react with the aluminum and cause corrosion.
 

Watermann

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Jan 12, 2013
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No way I would put a 50 HP motor on a 14' boat, that's way over max HP rating. Not sure why the 25 wouldn't push it just fine in the first place?

Small boats = small motors, sort of the way it works.
 

letitroll707

Cadet
Joined
Nov 20, 2011
Messages
24
The 50 hp is a short shaft and the 25 hp pushes great we were given the 50s and was wondering if it would hold thanks for the advice.
 
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