Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

[Paul Moir]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Lower unit is just about the same (will bolt on). Flywheel (I think) and ignition too. Carb is different although it looks identical, block is similar but won't fit. I think the crankshaft and rods are the same '56-'59. Pistons smaller, no thermostat in head, only single line water pump.<br /><br />Hope that gives you the idea! The 60s 40hp engines are closer (although they have a larger piston).<br /><br />If you knock the bearing out of the forward gear (light press fit), you can swap the forward and reverse gears, and you can flip the clutch dog. Usually the forward ears are bad but the reverse ones are good.<br /><br />Most the lower unit bearings are standard and can be found at your local bearing house - reverse ball ~$5, forward taper ~$30, pinion taper about the same, upper driveshaft ~$5 if it's the needle one.

 

[tiresmoker]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Yeah, I already did the swapperoo with the gears and the dog before I posted here. I have a '56 30 horse 'rude that came on my Larson, but when I tried to get it running I got really confused as to where everything was on the motor and gave up. <br /><br />I suppose there's no chance the gears will fit(I had to rebuild the lower unit due to sitting in a farmer's field for "15 years"), and the gears in that one are in absolutely perfect shape.<br /><br />Which is better: thermostat or no thermostat?

 

[Paul Moir]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

The gears ought to fit. Every couple years they'd make little changes here and there inside the lower unit, but I think the gears themselves stayed the same for a long time. Mostly they changed the bearings around, some (reverse compatible) changes to the clutch dog; that sort of thing. Pinion gear might be different but I don't think so.<br /><br />The thermostated engines are better. Better idling, better on gas, and last longer. Wish I could convert my 28hp (just like the 30hp) - might try someday.

 

[tiresmoker]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Cool.<br /><br />I might try using the 30hp's gears, then. I'd sure save some dough. Do the thermostats go bad often? The one that was in the 35hp started to open @ 150* and was fully open at 160*. <br /><br />It will take me a while to actually get the parts, but I'll keep you up to date when I make progress.

 

[tiresmoker]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

I was wondering, as this is my first boat, how does one measure the transom to select the right length of motor? I assume it is measured by the distance between the top of the transom to the lowest part of the hull? Mine is a little more than 15.5", so I'm guessing I would use a "short-shaft"?

 

[MCM]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Eric, consider the cost of the t'stat vs. hindsight, replace it now, I beleive it should be open at about 140 or so, your motor should be overheating at about 163.

 

[Paul Moir]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Correct on the transom. Here's how it's measured:<br /> http://www.iboats.com/ref/shaft_length.html <br />I think your 35hp measures more like 18" or so even though it's a short-shaft. Helps a lot for speed to raise the engine up a bit on the transom. <br />The longshaft Big Twins have a little 5" extension peice bolted between the lower unit and the exhaust housing.

 

[tiresmoker]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

I was thinking of making a raised transom plate for my boat. You guys would probably know the optimum position for the cavitation plate to be in relation to the lowest part of the hull?<br /><br />If my transom is 15.5" and the cavitation plate location is almost exactly 18", would it be right to raise the cavitation plate to be about 1" below the hull?<br /><br />Also, I got almost all of my parts, so I'll be posting on progress more often....

 

[lark2004]

Re: Low power and slight skipping? 1959 Johnson 35 Super Sea-Horse

Ideally, with these motors, we want the cavitation plate level with the bottom of the hull. Things get even better when you go a higher than that, to a point, but we can't do that with these old motors due to the way they pickup water for the waterpump.<br /><br />So try and get it level with the bottom.