50 hp evinrude won;t plane boat

[tom24]

Switched motors from a 1984 50 hp evinrude to a 1973 50 hp evinrude and the boat won't plane out. The mechanic I bought this motor from said the older motor has a much larger gear case and prop so the gear ratios are different wich will cause the boat not to plane.With my 84 I had no problem at all. The 73 seems to have half the power is this possible Thanks for the help,Tom

 

[Darian F.]

Re: 50 hp evinrude won;t plane boat

If everything is running correctly, good clean spark plugs, properly adjusted carbs, and timing is correct, (idle and fast timing)<br /><br />Then it probobaly is the prop pitch.<br /><br />A few other questions must be asked however,<br />Has your engine mounting height changed? What about the cavitation plate height, is it way high or too low.( It should be about level with the bottom of the boat give or take a little bit.)<br /><br />keep posting, <br />Darian

 

[daveswaves]

Re: 50 hp evinrude won;t plane boat

HP was measured differntly in 73 vs now,and rpm was lower, so that could be it, however, did you check to make sure it is running on both cyl? Half a fifty won't plane it. Easy way to check would be to pull both plugs, if one is wet and clean and the other is dryer and oilyer.....you are only running on 1.

 

[phatmanmike]

Re: 50 hp evinrude won;t plane boat

i had that same problem and same engine on my 16 foot center console. just what the last guy said... i was only running on 1 cylinder...<br /><br />give us more details about the boat and prop and we can help u better <br /><br />mike

 

[rickdb1boat]

Re: 50 hp evinrude won;t plane boat

I don't know what size or type boat you're running, but a 14-16 footer would require a 13 X 17 prop. That would be close...