40 hp slipping

[denislajoie]

When i hear on this forum, that johnson electramatic needs a special oil, what would be the symptoms of clutch slipping; cannot take off full throttle, but gradually, once at WOT suddenly, it the engine revvs, and the boat slows, and when it reingages, the whole boat shutters and then it kicks hard, this is what happened to me when i took my new to me motor out this week end.

 

[OBJ]

Re: 40 hp slipping

Your prop hub is slipping Denis. Commonly referred to as a spun hub. To check, take a marker that won't wash off and make a reference mark from the inner hub to the props outter hub. The outter hub is the hole the rubber inner hub goes into. After the problem occures again, remove the prop and check the reference marks. If they are not aligned, the hub is spun. Don't forget to include the splined section of the hub also in the reference mark.

 

[denislajoie]

Re: 40 hp slipping

really, i had no idea that a spun prop would be that bad, so does anyone know the symptoms of slipping clutches, im now curious, is the premium oil thicker or thinner than gear oil, and why can we not use type C oil

 

[OBJ]

Re: 40 hp slipping

Denis...what's the year of your engine?<br /><br />EDIT: The forward and reverse gears are engaged by springs that tightly wrap around a hub on the prop shaft. If the springs are broke you wouldn't move at all. If the hub splines are sheard, you might move a little depending on how bad the splines are sheard. But from your post, I would check the prop hub first.<br /><br />Premium blend oil for electric shifts used to be called Premium C by the old OMC corp. Just make sure the container says the gear lube is for electric shifts. It's thinner than mechanical gear shift lube.

 

[denislajoie]

Re: 40 hp slipping

sorry, its a 1967 johnson Super sea horse electramatic 40 hp

 

[OBJ]

Re: 40 hp slipping

I've Edited my previous post Denis....maybe it'll help.

 

[denislajoie]

Re: 40 hp slipping

oh i see, and the thick 80 w 90 is too slick to engage through the magnet

 

[lark2004]

Re: 40 hp slipping

waaaayyyyy to thick. The premium blend (that's what it's called now, sold by BRP) is similar to automatic transmision oil. How ever, I would advise that you use the genuine BRP premium blend oil. It's not all that expensive. Mine used one tube, and cost 15 dollars Australian. Which would probably be about 7 or 8 dollars US.