1972 omc 20 & 25hp whats the difference

[loganmallory]

hey<br />does anyone know what the difference is between a 1972 20 and 25 hp? is it just carb or is it bore or??? just wondering what parts are interchangeable.<br />LM

 

[Dhadley]

Re: 1972 omc 20 & 25hp whats the difference

The crank on the 25 is "balanced" but interchangable. The pistons are different (interchangable) with different wrist pin locations. The rods are the same. The heads are different and will make the most difference. If you bolt on a 25 head to your 20 make sure you richen up the carb (considerably) to compensate for the additional compression. That way you will avoid the hole in the piston like I had.<br /><br />Good luck!

 

[loganmallory]

Re: 1972 omc 20 & 25hp whats the difference

thanks Dhadley<br />I was wondering whether the stator assembly would fit-coils, points, etc. is the carb the same as well?<br />LM

 

[Dhadley]

Re: 1972 omc 20 & 25hp whats the difference

Yes. Everything will fit. Even a 3 cylinder carb will fit.<br /><br />Good luck!

 

[loganmallory]

Re: 1972 omc 20 & 25hp whats the difference

thanks dhadley. i switched everything over that i needed to and i cant beleive how awesome it runs. i'll catch some pickeral for you this weekend!<br />LM

 

[Dhadley]

Re: 1972 omc 20 & 25hp whats the difference

Have fun and an extra Colorado cool-aid. <br /><br />That'll work!