Re: 80’s/90’s 50hp opinions?

[chinewalker]

quote johnyrude200:

Good info to know. I just finished up, likely, the final run of my tritoon this season (yes, it’s Nov 20th, 51° out miraculously, and I waded into the water up to my knees to switch my prop). Not looking forward to pulling the docks out this afternoon. Once I thaw out on Monday, I’ll be able to get back on the blueboards 😯

The ’78 35hp johnson was struggling to turn 4300RPM at WOT with a 10 x 13 prop. Switched to a 11 x 9, and voila! Hit 5500RPM and gained a few MPH. If I can find a 10 x 10, I might even take another trial run this year. I do have a 10.5 x 11 4-blade prop, not sure what that will do (opinions)?

The motor is likely undersized for the boat, so I’m in the hunt for a 50hp motor, hence the genesis of this thread. Appreciate everyone weighing in on the pro’s/con’s. Now it’s just a matter of getting my hands on 2-3 of them so I can do the work on it myself as necessary!

It goes about 15-17MPH now, but I want 20MPH+ to get around. That’s enough speed for me.

You’re not going to get your 20mph without going to a bigger motor. 5500 is right where the revs will want to be. Going up in pitch will drop your revs and get the motor out of the sweet spot. Looking at your data, the 9P is the one you want. Lugging it with a higher pitch prop is akin to driving uphill, towing a trailer, in overdrive. The motor can build up heat, coke up the ring lands, and stick a ring into the cylinder wall – referred to as ring jacking.