60hp Johnson to a 135hp Johnson

a91eagletalon

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Oct 17, 2017
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I am going to be swaping my 71 60hp johnson for a 73 or so 135hp Johnson should it work out fine or is there thing I need to do as far as hooking up electrical is it all the same

Thanks
MJP
 

racerone

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Dec 28, 2013
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38,502
Totally different electrics and control box / shift control.-----You will need a control box with a---BIG RED PLUG ---on the end of the wiring harness.
 

a91eagletalon

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Like this one by chance
 

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a91eagletalon

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71 Crestliner Muskie 15.5ft i don't know what the hp rating is on it there is no visible information plate that i can see anywhere.
 

jbcurt00

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71 Crestliner Muskie 15.5ft i don't know what the hp rating is on it there is no visible information plate that i can see anywhere.

Info is out there if you look...
http://boatspecs.iboats.com/Crestliner_Boats__Muskie_15__1973/bp/66b23994

80hp +/-

That 135 will be " plenty " of power.

Yep, overpowered by more then 50%

Best of luck, boat safely and wear a PFD

FYI: in some states (like here in WV) overpowering a boat falls under reckless operation, by default, just being overpowered on the water, regardless of how you are operating the boat and or how diligent you are about staying out of the throttle.
 

a91eagletalon

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I understand the HP differences yes I am overpowering the boat ( Not by more than 50%) but yes more then the max yes the transom will be over haled and befed up anyone can be a menace on the water with any size of motor I don't plan on being reckless Plus my main question was about the electrical of the two motors
 
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jbcurt00

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71 Crestliner Muskie 15.5ft i don't know what the hp rating is on it there is no visible information plate that i can see anywhere.
If you dont know the rating, how do you know less then 50% overpowered?

.... yes I am overpowering the boat ( Not by more than 50%) but yes more then the max yes

Max 80hp
New motor 135hp

Half (AKA 50%) of 80 is 40
80 + 40 = 120

So a 120hp would be a 50% overpower, 135 > 120

If it was a 90hp max, the 135 would be 50% overpower
 
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