Propeller removal and installation

[FastFreddy]

I always thought the MC props with the splines looked like a better idea than the taper and keyway. Any experience with those? I know Malibu and the others are VERY unlikely to change the design but I was just wondering. Seems like they would be easier to remove without the taper.

Also would jamming it in reverse very quickly help loosen the taper?

Edited January 20, 2014 by FastFreddy

[Bozboat]

For me, I am a boater for recreation and I enjoy working on my Bu. I have learned so much from these folks. When I chime in to help someone it's just me sharing and paying forward what I have learned here and what I have learned by applying what I have learned here to my boat and her restoration and modification. I am not a professional mechanic, not an engineer or even an electrician, but knowing that I can tap into this forum and get good help fast has given me the confidence to tackle my boat repairs and maintenance myself.

[tvano]

as much as this topic is radiating negative vibes i'm going put on my asbestos shorts and add some new-ish (to me) info.

i touched base w acme back in may of '13. my q to them: we are having a discussion about prop removal and some in the thread are advocating lubrication of the prop shaft or use of anti-seize during assembly. what are your recommendations?

acme's answer: "We do not recommend the use of lubricants on the shaft".

[WakeGirl]

as much as this topic is radiating negative vibes i'm going put on my asbestos shorts and add some new-ish (to me) info.

i touched base w acme back in may of '13. my q to them: we are having a discussion about prop removal and some in the thread are advocating lubrication of the prop shaft or use of anti-seize during assembly. what are your recommendations?

acme's answer: "We do not recommend the use of lubricants on the shaft".

That's been addressed.

[Lance B. Johnson]

Well regardless of what any experts say I have lubed my prop shaft EVERY time. I also load my boat as heavy as I dare and run it that way all day. I clock lots of time like this. Guess how many keys I've sheared?

Guess how easy my prop comes off when I change it? Super easy. Someday that will make a big difference when I am at the boat ramp having to do an emergency change.

I'll always grease them. Just another case where engineering and real world experience don't jive.

[brad72]

I personally don't add grease or antisieze to a taper as it holds the 2 mating surfaces apart a little but I can appreciate as Ruffdog says that props can be a b**** to get off and time can be difference between a day on the water or going home. You will loose more props by not checking the shaft locking nut than a busted key and lets face it in the right conditions even an ungreased taper will come loose (vibrations and loose lock nut)

I lapped the acme 525 prop to the shaft when I fitted it over winter as I wasn't happy with the contact surface area after mating it up with bearing blue. After lapping I needed the prop puller to get it off even after hand fitting the prop, yet alone snugging up the nut. It did come off pretty painlessly before Christmas when replacing the strut bushes but I used a good prop puller that I made a good few blows with the hammer on the end of the puller.

Edited January 23, 2014 by brad72

[Lance B. Johnson]

Yup basically it comes down to the fact that greasing the taper doesn't matter and being the guy that can change a prop at the boat ramp in 10 minutes does.

[formulaben]

Some fun reading for when you can't get to sleep...

http://artec-machine.com/_images/documents/hydraulic_removal_coupling_hubs-keyed_keyless.pdf

[shawndoggy]

Why do you think prop pullers are necessary?

The harder it is to get off the better it was on.

Curious how Mr. footer explains this nugget: http://www.themalibucrew.com/forums/index.php?/topic/42722-how-to-install-prop/?p=601556

[WakeGirl]

He won't be explaining anything here.

[happypappy]

Some fun reading for when you can't get to sleep...

http://artec-machine.com/_images/documents/hydraulic_removal_coupling_hubs-keyed_keyless.pdf

I read most of the link. But now have a question…what material is the key made out of?? the link says it should be the same as the shaft, which is stainless steel, although not sure what kind….but having never really looked at the key, it always appeared to be brass, or at least some material other than SS??

ANd I have read several different TQ loads for the shaft nut…from 20 psi to 35 psi…which is a pretty wide range for the same application…which kinda gets back to the real question of who is right and how do they really know? vs, this is what I have done for however many years of boating and has always worked for me!

Edited January 23, 2014 by happypappy

[WheelerWake]

http://www.themalibucrew.com/forums/index.php?/topic/42722-how-to-install-prop/?p=601556

If the guys who make the props (ACME) say lube it, I might start lubing it. I haven't before and haven't had much trouble with the puller but I'm always in fresh water.

[brad72]

This is one of those cases where both are right and both are wrong depending on the literature on prop istallation. Traditionally tapers rely on the friction between the surfaces but Acme does say do add some grease to aid in removal. Obviously the grease will wash out over time so the fit may become a friction fit eventually and the nut may need snugging up as the grease washes out.

I reckon proper maintenance and inspection before each outing is best. When checking the bungs before launching, inspect the the prop nut and give the prop a wiggle. Job done.

[Lance B. Johnson]

Well so here's what I don't get. If no one has had a failure because they grease the taper then why not? It makes no difference except in removal so again why not?

Understand that acme is going to give you the CYA reply every time.

[happypappy]

This is one of those cases where both are right and both are wrong depending on the literature on prop istallation. Traditionally tapers rely on the friction between the surfaces but Acme does say do add some grease to aid in removal. Obviously the grease will wash out over time so the fit may become a friction fit eventually and the nut may need snugging up as the grease washes out.

I reckon proper maintenance and inspection before each outing is best. When checking the bungs before launching, inspect the the prop nut and give the prop a wiggle. Job done.

So a prop on a tapered shaft torqued down to 25-35 pounds…what does giving the prop a wiggle do? ANd how do you properly inspect and maintain that?

It is not whether it is fresh, brackish or salt water, it is the chemical reaction between 2 dissimilar metals.

Edited January 23, 2014 by happypappy

[justgary]

Brad72, I'm not surprised it stuck after you lapped your prop to the shaft. I once saw two 2" discs of flat optical glass that had been slid together in a clean room 10 years before. The interference fit was so tight that I could not pull them apart. They were so flat that essentially *no* air molecules were between them to apply any resistance to the 14 PSI atmospheric air pressure pushing them together. Over just that small area, they had about 45 pounds of force (from atmospheric air pressure) holding them together. Not bad for just two pieces of round glass stuck together.

The same thing happens in a taper, and it gets even better when the parts fit together perfectly, like lapping can produce. Theoretically, water can't get between them either, but in reality the tapers don't fit that well for the whole length unless you do lap them, and you can get electrochemical action even without water between them.

In actuality, I suspect that ACME may have tried a bunch of props on a bunch of boats (and probably mostly near their factory in Michigan), but I have to wonder if they have ever even pulled one of their props from a shaft after it has seen salt water use for several years. They would only have to do it once.

I'm pretty sure that this question is completely academic to most of us here. Us shaft greasers know who we are, and all you non-greasers just haven't had the need to do it yet....

If you want more academic fun, consider the difference in applying torque to a nut on a dry thread as opposed to a nut on a lubed thread. The force applied by the nut is dramatically different, and yet it's the same torque! Should you lube the prop nut threads, or leave them dry?

[brad72]

I feel we should be sitting down with a glass of scotch pondering this question and to be honest we are all right, grease or no grease as our boats work and none of us have had a failure. If i were to remove my prop regularly though I think I would grease it like acme recommends

HappyPappy, the wiggle was a loose term just to see if for some unknown reason the prop nut has come loose and taper let go. If your nut is tight then it will never let go, not even if you hit something. But since you are checking the bungs, what can it hurt. We have people over here who steel or try to steal props from boats so not unlikely that the nut could be gone in an attempt to get the prop off.

Edited January 23, 2014 by brad72

[happypappy]

I feel we should be sitting down with a glass of scotch pondering this question and to be honest we are all right, grease or no grease as our boats work and none of us have had a failure. If i were to remove my prop regularly though I think I would grease it like acme recommends

HappyPappy, the wiggle was a loose term just to see if for some unknown reason the prop nut has come loose and taper let go. If your nut is tight then it will never let go, not even if you hit something. But since you are checking the bungs, what can it hurt. We have people over here who steel or try to steal props from boats so not unlikely that the nut could be gone in an attempt to get the prop off.

Gotcha. I always do a prop check too…checking for dings, crap wrapped around the shaft, etc. But I keep the boat spotless, so it is part of the walk around or swim around when it is in the water. In decades of boating, I have never had a prop nut come loose…knock on wood. ANd some one mentioned they had sheared the brass key…which I had never seen or heard of.

I wonder if I think it was Nitrous who had the bad experience with the broken prop pullers, and if a bit of grease would have prevented that?

[dalt1]

I grease and also remove my prop every spring as preventive maintainence. Take it off, clean it and put it right back on. Don't want to deal with a siezed prop after several years of not being removed.

[formulaben]

I grease and also remove my prop every spring as preventive maintenance. Take it off, clean it and put it right back on. Don't want to deal with a siezed prop after several years of not being removed.

Me too. I know it is unlikely to seize in fresh water but I consider it preventative maintenance.

[Malibuss]

as cynical as some of the comments were, it still brought about a very healthy debate here. I appreciate that actually. I think the lube is a handyman's special and most of us would do that on the shaft/prop as we would lube our squeaky dry wheel lug nuts, but you are not supposed to in either application due to proper torque and friction fitting

[Afun]

I personally don't add grease or antisieze to a taper as it holds the 2 mating surfaces apart a little but I can appreciate as Ruffdog says that props can be a b**** to get off and time can be difference between a day on the water or going home. You will loose more props by not checking the shaft locking nut than a busted key and lets face it in the right conditions even an ungreased taper will come loose (vibrations and loose lock nut)

I lapped the acme 525 prop to the shaft when I fitted it over winter as I wasn't happy with the contact surface area after mating it up with bearing blue. After lapping I needed the prop puller to get it off even after hand fitting the prop, yet alone snugging up the nut. It did come off pretty painlessly before Christmas when replacing the strut bushes but I used a good prop puller that I made a good few blows with the hammer on the end of the puller.

Recently during my prop removal, I realized the stock 1235 that came in my Bu' did not have any grease on it from factory. Used the OJ Prop puller. Tightened it pretty good and banged the back of the prop near the tapered base with a lead hammer. It came off on the first strike. I did not use any lube or anti seize in assembly. I think if I mess up my prop during a boat outing, I would probably call it a day.

[Bawshogg]

True if you are near home.

Sometimes we go on week or weeks long trips to lakes 5-6 hours from home. I sure wouldn't wanna tow my boat all that ways, ding a prop the first or second day out and not be able to use the boat the rest of the trip.

I had this happen last summer and had to drive 4 hours round trip to Bakes to get parts to fix it ...........it was more than just a prop though.

[williemon]

I replaced the stock prop on my 01 when i got it used a few years ago. It was a pain to get off. I wished i had put a lube on the new prop. Ive since tried to get my current prop off just because but stopped short because it would not budge. I will try again this winter and you bet i will apply some sort of lube on the reinstall.