Propeller runs when I start the motor

[dglvr22]

I just bought a 1973 Johnson 50 HP motor with electric start/controls. When I start the engine the propeller starts spinning as well. I'm assuming that's not normal and I need to adjust something. What do I need to do?

 

[OptsyEagle]

Re: Propeller runs when I start the motor

Actually it is normal. Since the gear case is completely emersed in high viscosity oil and the drive shaft is always spinning, even when you are not in gear (in neutral), the centrifugal force that the drive shaft gear makes this oil, will tend to turn your propeller.

 

[Dhadley]

Re: Propeller runs when I start the motor

Are you saying the prop is turning fast enough to move the boat when it's in the water or is it kind of just "floating" around? Are you sure it's a 1973 and not a 72?

 

[dglvr22]

Re: Propeller runs when I start the motor

I haven't had it in the water yet but have just started it to make sure everything was hooked up correctly. I think that the propeller seems to be moving kind of quickly. I'm pretty sure it's a 1973 but I'd have to look at it to be sure and it's up at the cabin.

 

[wbeaton]

Re: Propeller runs when I start the motor

I think what Dhadley is asking is if its turning "kind of quick" or really racing fast - like no need for a fan sort of fast.

 

[OptsyEagle]

Re: Propeller runs when I start the motor

Yes. I should have made the distinction that when I said it is normal for the propeller to turn when in neutral, I didn't mean that you should be able to pull up a water skier or anything like that. If that is the case you definitely have a gear or shift lever issue.

When my 9.9Hp is in neutral, it will move my 14' boat a little, but at a speed less than about speed 1 on my 30lb thrust trolling motor.

 

[tashasdaddy]

Re: Propeller runs when I start the motor

whats the model number on the motor, let's determine if it's a 72 or 73, because the lower units are different animals.