1956 Johnson 10hp - prop slippage

[ricklab]

When I apply full throttle from a stand still my prop slips.

I am able to rotate the prop by hand with the motor in gear. Is there a rubber hub that wears out that causes this. Can it be fixed or is it better to purchase a new prop?

 

[Chinewalker]

Re: 1956 Johnson 10hp - prop slippage

Yes, yes, and yes. There is a rubber hub between the center and outer metal parts. This hub can be replaced by any good prop shop. New props are still available, probably even through an Evinrude/Johnson dealer, or anyone who handles Michigan props. Used props turn up on eBay all the time...
- Scott

 

[wbeaton]

Re: 1956 Johnson 10hp - prop slippage

Are you sure Chinewalker? Doesn't that prop have a shear pin that goes through the prop shaft and seats against a notch in the shaft. Pull the prop and check the condition of the pin.

 

[F_R]

Re: 1956 Johnson 10hp - prop slippage

If you can rotate the prop by hand, it probably is the shear pin. The hubs will slip under horsepower long before you can turn it by people power. If you can rotate the hub by hand it is grossly shot.

It probably is cheaper to replace the prop than to have it rehubbed if that is the problem.

 

[darrklim2]

Re: 1956 Johnson 10hp - prop slippage

Are you sure Chinewalker? Doesn't that prop have a shear pin that goes through the prop shaft and seats against a notch in the shaft. Pull the prop and check the condition of the pin.

Obviously I am no expert, but I searched for a prop for a 56 johnson 10hp and this is what I found here on Iboats:

http://www.boat-props.com/propeller..._id=13&**********=508622597&*******=513843153

According to this it is a 13 spline with a Urethane cushioned hub.

 

[F_R]

Re: 1956 Johnson 10hp - prop slippage

I don't see where it says that is for a 1956. But I am very certain that a '56 is a pin drive. Unless somebody has changed the prop shaft.

 

[Chinewalker]

Re: 1956 Johnson 10hp - prop slippage

The prop is driven by a pin. BUT, the poster said that it occurs when he applies full throttle. I took this to mean it still worked at lower speeds. A sheared pin would give absolutely no drive at all and would slip with no resistance... If this prop is as old as the motor it is quite possible the hub is shot enough to be able to spin it by hand...
- Scott

 

[samo_ott]

Re: 1956 Johnson 10hp - prop slippage

If it spins by hand I think it's the shear pin also. Very easy to check, just pull the cotter pin and check.

 

[ricklab]

Re: 1956 Johnson 10hp - prop slippage

The prop works fine at low speeds. It only slips when I apply more power. Thanks for all the information. I will remove the prop tonight and look at the shear pin as I do have a spare pin. I also located a new prop by Michigan Wheel for $69.98 from itgmarine.com. Seems like a reasonable price for a new prop.

 

[samo_ott]

Re: 1956 Johnson 10hp - prop slippage

Chinewalker was right then, if it works at low speed and not high speed, it is most definitely a spun hub and a new prop is in order.

 

[wbeaton]

Re: 1956 Johnson 10hp - prop slippage

I thought "I am able to rotate the prop by hand with the motor in gear" meant it was loose on the shaft. Either way, it looks like you need a new prop. Personally, I'd check out eBay or better yet your local marina and see if they have any used props kicking around. It'll be much cheaper and possibly factory correct.

What prop are you looking at? I don't think the first one you posted is for your motor. Yours is definately a pin drive and not splined.

 

[dragit]

Re: 1956 Johnson 10hp - prop slippage

ricklab,,help us out when you get that new prop with the pt#.......

 

[lindy46]

Re: 1956 Johnson 10hp - prop slippage

The prop works fine at low speeds. It only slips when I apply more power. Thanks for all the information. I will remove the prop tonight and look at the shear pin as I do have a spare pin. I also located a new prop by Michigan Wheel for $69.98 from itgmarine.com. Seems like a reasonable price for a new prop.

If the prop is otherwise in good shape, you can have it re-hubbed for $35-40.

 

[tjandrews]

Re: 1956 Johnson 10hp - prop slippage

Are you sure Chinewalker? Doesn't that prop have a shear pin that goes through the prop shaft and seats against a notch in the shaft. Pull the prop and check the condition of the pin.

I have a '54 10 hp that definitely has a drive (not shear) pin and rubber hub. The prop was spun when I got the motor, thrown in with an aluminum boat I was considering to sweeten the deal. That was before I was on the Internet, back some 10-12 years ago. I wound up going to a dealer for a new prop, which at that time cost me about $65. I checked, and it would be over $100 from that dealer now.

 

[tjandrews]

Re: 1956 Johnson 10hp - prop slippage

I have a '54 10 hp that definitely has a drive (not shear) pin and rubber hub. The prop was spun when I got the motor, thrown in with an aluminum boat I was considering to sweeten the deal. That was before I was on the Internet, back some 10-12 years ago. I wound up going to a dealer for a new prop, which at that time cost me about $65. I checked, and it would be over $100 from that dealer now.

Whoops. Didn't realize that this thread is over 2 years old. Here on iboats, they list the Michigan part # as 012013 for the standard 9 1/4 x 11 prop. Other pitches are available, depending on the motor's application.