40 h.p. power head compared to a 60 h.p. power head

[hutch6575]

Hello everyone,<br />I have a question that might be kinda off the wall. I cracked the power head on my 1984 60 h.p. jonny and my buddy has a 1984 50 h.p. jonny that has a 40 h.p. power head on it. The reason i say it is a 40 h.p. power head is that on the top of the engine there is a round silver tab made into the the engine and it has j40 but on the bracket it has j50.after looking at the engines from the outside with the cover off they look the same. I am curious if its the bore size that makes the difference. Also will the carbs off of the 60 h.p. work on the smaller engine? both of the 1984 engines are the 2 cylinder style.

 

[phatmanmike]

Re: 40 h.p. power head compared to a 60 h.p. power head

i have a 1981 50 hp evinrude 2 cylinder, and as far as im told, the 40, 50, 60 are all the same with carbs being the main diference.. if you look up in any parts book for these motors, youll see that a ton of the parts are the same, i also believe that yes, the carbs will all fit, its just the jetting thats diff! hope this helps

 

[G DANE]

Re: 40 h.p. power head compared to a 60 h.p. power head

Howdy Hutch6575<br /><br />There was a thread of exactly this some time ago -do a search on 40 versus 60HP. The 40 and 50 are very clouse - same block, but different reedassembly and carbs - as far as I remember the 60 is much different.

 

[alcan]

Re: 40 h.p. power head compared to a 60 h.p. power head

These engines are all from the same family. they my look the same on the out side and many parts are the same. There are some very important differences on the inside. And no you will not get 20hp more by switching carbs. Fact is it will be less if it will run at all.

 

[Dhadley]

Re: 40 h.p. power head compared to a 60 h.p. power head

We've done it many times. There are some differences, mainly in the reed stops. Use the 40 hp powerhead, your 60 hp head (very slight difference) and your carbs and reeds (either intake).<br /><br />The motors are rated at different rpm's. It has nothing to do with where they run, just the rpm the OE rates them at. <br /><br />Thre were several castings and there is one in particular that the SST45 guys look for. That casting showed up in 40's as well as 60's.<br /><br />Good luck!