60 hp mercury prop continues to spin when in neutral

[Canman2018]

Why does the prop continue to turn when in neutral gear.?

 

[QBhoy]

Perfectly normal to spin a wee bit in neutral. If you mean it’s spinning as in fully engaged in gear and capable of driving boat forward...that’s different.

 

[racerone]

Normal on a hose running in the driveway.

 

[GA_Boater]

Why? The pinion gear on the driveshaft is always turning, even in idle. The spinning gear is causing an eddy current in the lube which is directed against the reverse gear making the prop spin lazily in the forward direction and can be stopped with a finger. There is no power, but for safety's sake, use a stick or just trust us.

Normal.

 

[racerone]

Really------Is the oil not directed at the forward gear too !!------I would say that the forward gear has a different bearing set-up than reverse and that is what causes the propshaft to spin.----Not sure where this eddy current thing comes from !

 

[GA_Boater]

Really. Next time you drain a Merc lower, fire up the motor for a few seconds. Tell me if the prop does the lazy spin.

The forward gear is disengaged and reverse is always coupled on the prop shaft. The pinion acts as a windmill causing oil to spin like a whirlpool or eddy, driving against the reverse gear. Forward is probably driven too, but the thrust hub isn't against the forward gear.

 

[racerone]

Nonsense.------Forward and reverse gears both turn when motor is running.

 

[racerone]

GA----When is the last time you rebuilt a gearcase to see how things work ??

 

[GA_Boater]

Let's agree to disagree and leave it at that.

But we do agree that a weakly spinning prop in neutral when running on a hose is normal.

 

[racerone]

And it is because the bearing set-up on forward and reverse gear is DIFFERENT.