Should the prop have any play

[chaseo88]

I just replaced the water pump on my 1994 outbard force 120hp. And I got the nut on there pretty tight for the prop, I do not have anything to torque with. The shaft does not move but the prop has about an eighth inch of play Going forward and backwards.. Is this normal or doesn't need to be tighter? I just feel like I have it on very tight, And any tighter could maybe cause a problem.

 

[airshot]

Some do have play, however, be sure you have all the proper washers, spacers etc. In place before tightening. Most gave some type of a tabbed safety washer so the nut can't come loose.

 

[chaseo88]

Some do have play, however, be sure you have all the proper washers, spacers etc. In place before tightening. Most gave some type of a tabbed safety washer so the nut can't come loose.

Okay thank you, and yes it has one of them tab washers

 

[jimmbo]

If the shaft is not moving in and out, there likely a Washer/Spacer missing. Especially critical is the Thrust Washer, without it, the Prop can end up machining the back of the Gear Housing, and that gets expensive in a hurry as it would have to be replaced

 

[Chris1956]

The prop should not move on the propshaft splines. Movement of the prop on the splines will likely cause damage to the gearcase, propshaft or other parts.

The entire propshaft may have some small play, and it is usually normal. 1/8" play in the propshaft is about what I have on my Merc and Johnnyrudes.

 

[Texasmark]

The lower unit contains an "overrun clutch" that is a saw toothed set of gears that allows the engine to slow down when decelerating but allowing the prop to follow the forces acting against it, by flowing water, as the boat slows.

As the F gear (only has this function) and the "clutch dog" mounted on the prop shaft accomplish this, there is spring loaded pressure on the prop shaft whereby turning the prop without the engine running (and you pushing on the prop while turning it) will cause the clutch dog to move up the ramp which will force it to the rear and abruptly move forward slightly (1/8 to 1/4" type thing) as it falls off the peak of the saw tooth ready to repeat the cycle.

Speck on the prop nut is 55 PSI. Putting a block of wood between a prop blade and the AV plane, using a 1/2" breaker bar which is about 15 or so inches long, 55 is moderate pressure on a wrench of that length, hand on the end.....no slop.

To check the installation, grasp the blades of the prop with your hands on either side and push forward while turning the prop. As the prop follows the sawtooth pattern, there should be no contact between the prop and the housing.

 

[dingbat]

Speck on the prop nut is 55 PSI. Putting a block of wood between a prop blade and the AV plane, using a 1/2" breaker bar which is about 15 or so inches long, 55 is moderate pressure on a wrench of that length, hand on the end.....no slop.

Guessing you meant 55 ft/lbs of torque

Really need to follow the manufacturers specification for a particular motor. The spec for my motor/prop is 80 ft/lbs.

 

[Texasmark]

Guessing you meant 55 ft/lbs of torque

Really need to follow the manufacturers specification for a particular motor. The spec for my motor/prop is 80 ft/lbs.

Brain fart!!!! Sorry. On the amount my serv. man. for my 115 is 55 ft-lbs. He said he had a 120.....close enough for me.

 

[Stinnett21]

Torque spec on my alpha 2 drive is 55 ft/lbs minimum. So I tighten to 55 then if no tabs line up continue tightening until they do.