What do I torque my prop nut to?

[mjdean]

Hello All. I just replaced my strut and prop on an 88 mariah and am wondering what the prop nut should be torqued to. I've searched and googled and see anything from 30-80 ft. lbs.

Thanks

[1000springsskier]

I torque my 88 Saltare to 50 ft/lbs. Never had a nut come loose. As important as torque is making certain your key and keyway are in good shape. Clean and smooth with a nice, easy fit. I always put my propeller on without the key, push it up as far as it will seat by hand and mark the shaft at the top of the propeller. Then I remove the prop, install again with the key. Prop should be close to your marked line. Then I tighten to the 50 ft/lbs. Prop always meets, or slightly covers my marked line. I have a 1" shaft. Might go a little more for larger shafts. Not sure about that.

[docdrs]

30-35 ft lbs

[mjdean]

Thanks guys. I tightened to 35 ft. lbs. All is well.

[SquamInboards]

Most importantly, install a cotter pin behind the nut, even if it's nylock.

[chris young]

My usual PSA. Lap fit that prop. I did mine per this; https://www.youtube.com/watch?v=2ozh4JjoWm4. I lost my first prop because it wasn't properly fitted, and I didn't notice that the cotter pin was gone. I went the extra mile and heated the prop in the oven before I put it on. I hope I never have to remove it

[docdrs]

My usual PSA. Lap fit that prop. I did mine per this; https://www.youtube.com/watch?v=2ozh4JjoWm4. I lost my first prop because it wasn't properly fitted, and I didn't notice that the cotter pin was gone. I went the extra mile and heated the prop in the oven before I put it on. I hope I never have to remove it

wow , i love it when i learn something new, now i feel like i should do this to my prop

[Jetlink]

"Allow prop to thaw in fridge for 24 hours, preheat oven to 375. Place prop on a 15x15 gray non stick pan and bake for 20-25 minutes or until golden in color. Remove and run like mad for your boat."

[mjdean]

Ha Jetlink. That's awesome. Great idea. I've done that with crank bearings for a snowmobile. I'm gonna pull it and lap it, then re-seat.

[docdrs]

I can understand lapping a prop and shaft but heating a prop up to put it on just sounds like you will have one hell of a time getting it off in the future. Heat is often needed to take props off that were not heated to put on and probably not lapped. Checking the torque after first use , nylock and cotter pin should be more than sufficient imo. But I've only been dealing with boats for 20 years. Just my .02