Stainless Nuts

Has anyone ever run into a problem having a stainless steel prop nut on a stainless drive shaft "lock up". we tried to change prop today and the nut would not thread off all the way. it got "bound up" and we ended uo having to cut the nut off and fix up the threads on the shaft, put new prop and BRASS nut on and all is good now. I was told by two mechanics that stainless nut on stainless shaft should NEVER be used as the threds "lock up" and well u read the story. Anyone else ran into this or heard of it. Damned stumps bent my prop now I have to get repaired,glad I have extra prop.

always use anti seize on stainless fasteners and never use an impact

I've heard the part about Stainless on stainless will "lock up"

i was told even the anti seize may not always work because of the exposure to chemicals ect.. in the water that washes away the ingredients that makes anti seize work. we used the anti seize, but maybe not enough? I will not use the stainless nuts anymore, a 15 min. job took 2 hrs as I had to tow boat down to a friend who has the tools required to get the job done. needless to say we did not make it to the lake today and that sucks.

Stainless on stainless threading will result in a phenomenon called "galling" where the metals can actually fuse together. Some fastener companies call it "cold welding". Use a helluva bunch of lubricant, use different alloy grades (i.e. 302 and 316) for the nut and shaft, or don't do it at all. My .02.

thats the term they used, "galling", whatever it is, it SUCKS. seems that the easiest solution is the brass nuts. I'm still pissed we missed an evening of ridin'. I was dying to burn up some $2.85 gal. gas. It's going to be an expensive year, props, gas, beer.... I need a raise.

Yep, stainless on stainless can definately sieze. What amazes me is how easily it can happen. I have been threading a nut on by hand and had it get stiff, put a wrench on it and within one turn it was siezed and had never even come close to getting tight (still a visible gap between the bottom of the nut and where it needs to get tightened down to.

If you are taking a nut off a dab of oil on the threads will help. If you are putting something together a bit of anit-seize will help you get it apart again later.

Be careful using a non stainless nut, as dissimilar metals can create corrosion problems. You may find that the nut falls off all by itself after a relatively short time.

We pretty much use stainless hardware on everything onboard my fishing boat that operates on the bearing sea. We really dont have any issues unless the treads are tweeked or the improper picth was used and someone forced the nut on in the first place. I would not use a stainless nut on a bronze or brass shaft simply because of the hardness issues. If I had to take a guess I would say that the threads were rolled or there was some grit and grime and that is why the nut would not pass. Something as simple as a rock being kicked up while trailering the boat could kick or roll over a thread on a shaft pretty easily. Always inspect and clean the end of the shaft before attempting to back the nut off. Keep a thread file handy in your tool box and gently clean up any burs before you begin. It will save you a lot of time. When your done you can wrap the end of the shaft with some electricial tape or use a small piece of hose to protect the end of the shaft and threads.

I love stainless!

greg, it was a stainless nut on stainless shaft, the threads were ok behind nut thats why we were so surprised when the nut became stuck as i had small amount of anti seize on it as well. your suggestion of the tape on exposed end of shaft is good idea and the thread file is what we used to clean up the threads after we cut the nut off. grit or grime could explain the problem as it could have worked it's way into the threads, whatever happened, it sucked. was at the MC dealer today and picked up a spare brass nut and the techs there said they have seen the "galling" as well and only use brass nuts. hope this thread helps others avoid the hassle i had to go thru. ( nice B52 in your profile, i have looked around our part of the country and have seen none. r u happy with it?)