Why did my prop fall in the lake

[10000lakes]

Johnson 9.9 1976
Unfortunately this is not a joke.
I bought a new old prop(it was the correct prop9-1/2x10 three blade) put on the nut and cotter key-took it out for a spin and lost the prop.
What did I do wrong?
My factory manual doesn't go into great detail about putting on a new prop. It shows a thrust washer. Is this something that is on the prop? What is the proper nut torque?
Can someone explain to me how to correctly put on a "new" prop?since I am obviously missing something.

Thanks

 

[rndn]

Re: Why did my prop fall in the lake

Maybe your pin fell out. Did you use a new pin as you always should?

 

[tashasdaddy]

Re: Why did my prop fall in the lake

if you did not have the thrust washer, there was enough play for the torque, to break the pin, and the in reverse the nut backs off along with the prop. had it happen back in the -70's. in a clear lake, was able to dive and recover everything but the pin.

 

[rickdb1boat]

Re: Why did my prop fall in the lake

These are the parts you should have for your prop...

 

[F_R]

Re: Why did my prop fall in the lake

That motor has a splined prop shaft. There is a 318966 thrust washer forward of the prop. This one is what the prop pushes against, and is vital--without it the prop will rub on the gearcase and cause major destructiion. There is also a 318959 splined thrust washer aft of the prop. The splines prevent any tendency of the prop to rotate the nut.

There is no way that nut came off if you had the cotter pin in there and the ends spread. You forgot something. Or the cotter pin ends were fatigued from being bent back and forth and broke off. Always use a new STAINLESS STEEL cotter pin.

Put some waterproof marine grease on the shaft, slide the parts on, snug the nut down then back it off to the first cotter hole, and do the pin.

 

[10000lakes]

Re: Why did my prop fall in the lake

thanks for the help. Just to clarify in my mind...the thrust washers are seperate parts that would not have been incorporated(part of) with the prop?

I am not sure what caused the failure I honestly don't remember any thrust washers on there before. There is nothing on the spline shaft now(although it looks to be in good condition)
I guess I am at square one...
Where to get these parts? NAPA?
tashadaddy-I wish the water on this lake was clear!! I am still plotting a way to find that sucker since it is not a deep lake and I know the general vacinity of failure.

I am much wiser for the next time!

 

[Silvertip]

Re: Why did my prop fall in the lake

Your Johnson/Evinrude dealer should have them. If not, try Twin City Outboard or any of the prop shops.

 

[F_R]

Re: Why did my prop fall in the lake

The picture posted above by rickdb1boat show the thrust washers #32 and 46. Ignore # 53, it is the rubber hub that is part of the prop and does not come out by any methods used by us mortals. Any Evinrude or Johnson dealer should have these parts or be able to get them for you.