Reuse Mercury Prop Nut and Washer?

S

Sea Wolf

New member
We recently brought home our 24 ft pontoon boat for the winter and left the CD-22 in the marina slip instead for the upcoming fishing season. I need to take off, slightly repair, clean up, and paint the prop as well as check behind the hub for fishing line and any possible damage to the shaft seal.

Can I reuse the nylock nut on the propshaft and the tanged washer also used in the Mercury system? Reusing nylocks is usually limited to once or is sometimes totally prohibited in certain situations, such as in aircraft, as I understand. What's the generally accepted and / or factory recommended procedure here? Thanks, Joe.
 
You can, but I wouldn't, but of course I have an aircraft background. Take the used ones and add them to your spare set -- they're the last ditch ones to use.
 
Joe,
My previous boat had a 90HP Honda, which I am told had a Mercury lower unit(1997 year). I used the same prop-nut and washer for 7 years and it went through at least 7 cycles of annual checks. I never occured to me to change it.
 
I have just a bit of experience with aircraft as a crew chief and co-pilot. Of course you are correct that these nuts are not to be re-used on aircraft. It is quite difficult to pull one over to the side and set out a flare. On a boat it is quite a different matter. The only question you need to ask yourself is how long you are willing to float about until rescue arrives. If you have twin engines or a good kicker that can push you through a receding tide and/or headwind, you can probably reuse the nut forever. Just know what will occur if the nut decides to back off.
 
Joe,
I think, if memory serves, the funny tabbed washer prevents the nut from turning. So if the tabs are not fatiqued and you get them in the grooves, it would be impossible for the nut to turn. I remember the Honda shop manual called for a certain amount of torque( in the range of 20-25 lb-ft?) so there would be no slop and it didn't call for a new nut each time you checked the prop and greased the shaft. I wouldn't lose any sleep over it. At most I might replace the tabbed washer if it got too mangled.
 
Ken and all:

Thanks for the advice!

I've decided to look carefully at the nylon part of the washer that holds it on and see what resistance to backing off it provides, first.

Then I'll look for metal fatigue on the tabs of the brass washer where they fold up to hold onto the flats of the nut.

Shouldn't be too hard to determine if any of the parts are sub-critically worn and failure prone.

Thought about using a small torch to melt the nylon back towards smooth and thus remove the existing threads cut into it by the propshaft threads, which would renew the locking mechanism, but this is probably is not a fully renewing procedure, as some nylon is lost in the thread cutting process.

The latter all sounds like an el-cheapo approach, but there are times you can't find the right nylock nut with the appropriate threads at the local hardware store, or are out somewhere with nothing available except what you've got on the boat.

Might be nice to have a small tube of quick drying adhesive available on board that would fill in the worn places and allow you to reuse nylocks. 5-minute epoxy would probably do the trick.

Thanks, all! Joe.
 
BC-

I use it already on other applications, both the red and the blue, but not sure I want it on my propshaft, but probably can't hurt to use some of the blue, especially since the shaft has some light oil coating on it unless you remove it with a fairly hot solvent. Thanks! Joe.
 
For goodness sakes, go spend a few bucks and buy some new nuts. :shock:

Maybe that didn't come out right.

Almost when they asked Pres Bush about how he felt about Roe Vs Wade. He is reported to have said.... "I don't care about how they got out of New Orleans, as long as they got out".....

And I'm a Bush suporter, but I won't go there.... :smilep :smileo
 
Joe,
I thought I had the same lower unit, but maybe not. On my Honda, the washer tabs are bent down to fit in slots cast in the lower unit. If you bent the tabs up around the prop-nut it would not do any good. Also on the Honda the tabbed washer was SS and very tough. I think with care it could have been used forever.
 
Charlie-

Would that I could, I would!!! Would be nice to feel 18 again! Which store do you recommend?

Cavu Ken- Actually upon closer opbservation the "washer" is star shaped with two tangs bent up along the nut flats, and two tangs with Y shaped ends that fit over raised prongs on the back of the prop, locking the nut, washer, and prop together.

(See, Charlie, I managed the last paragraph without any reference to flat nuts, split ends, or raised tits. But then I was a school teacher and not in the Navy!)

BC Ken- My new Lincoln welder arrives next week. Please send your department account number at the college along promptly so that I may forward it to the folks at Lincoln.

By the way, Ken, do you know of any solvent for Red Locktite? I'm typing this one handed with the other one stuck to the propshaft with you know what. Unfortunately the motor and the 24 foot pontoon boat won't fit through the back door to the house, so it looks like I'll be spending the evening in the RV barn. Now if I can just reach the porta-potti that's stored up there on the top shelf...........
 
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