Prop is stuck

[Sparky450]

3 hours ago, Slurpee said:

I didn't see it mentioned yet.

Rotate the prop puller 90 degrees around the prop every attempt. That can help walk the prop off with the deflection you get from the puller. I had one prop with a sheared key and it spun nearly half way around and froze.  OJ gave me this tip and after about the 3rd time around putting a lot of umph on each attempt it popped off.  I was using a torch to heat the prop every iteration as well.  GO EASY!

Another more drastic approach - requiring complete patience and sobriety mind you - is to use a dremel and some cutting fluid and a bit to drill down the length of the slot in the prop and remove halve of the key material that sheared off.  This reduced the binding force for me once after several drilled out sections that it just came off.  

Now after two PITA ridiculous prop pulls when I put a prop back on I use just the thinnest amount of water proof grease on the shaft.  Now those things come off pretty text book every time no matter what.

Can you tell me what grease. I have had two of these issues.  First one prop had been on for a number of years.  But again a sheared pin. I always run the brass pins. No stainless. I would rather a sheared key. 😃

[Sparky450]

I HAD a friend who lost his life to the old 2 part wheels with a ring.  He didn’t put a pry bar through the holes in the wheel, to catch the ring if it failed.😩

[Eagleboy99]

Grease is a sure-fire route to over torquing the prop on install.  Tribologists everywhere are cringing... 

[Slurpee]

6 minutes ago, Eagleboy99 said:

Grease is a sure-fire route to over torquing the prop on install.  Tribologists everywhere are cringing... 

That happens anyways. And the prop pushing the boat tends to do the rest. Honestly take a sec to do the math on the forces on that prop pushing it up the shaft when we operate the boat. And that the service manual calls for tightening the prop but up after a few hours of use after install. None of us monkeys with a big ten inch wrench are gonna make that torque the engine does.

The grease helps reverse the process without threads like this. Just be reasonable about tightening the nut up. Cuz yeah a big enough monkey can break anything  

I’ve used a very little bit of the same grease I use on my hoist from BH USA. I’ve also used the same ball bearing grease I use on my bike. Phil’s I think it is. 

[MLA]

23 minutes ago, Eagleboy99 said:

Grease is a sure-fire route to over torquing the prop on install.  Tribologists everywhere are cringing... 

I disagree. If the nut is being used to seat the prop, you're doing it wrong. The nut is there to keep the prop from coming off. A fully seated prop will not move up the shaft any further with a nut at 32ftld.  

[MadMan]

23 minutes ago, Sparky450 said:

I HAD a friend who lost his life to the old 2 part wheels with a ring.  He didn’t put a pry bar through the holes in the wheel, to catch the ring if it failed.😩

Sorry to hear that.

Many decades ago I was getting a tire changed on a 2 piece rim at a gas station.  The guy was jumping on the lock ring trying to get it to seat.  I left the building.  Nothing happened, but I couldn't watch.

[oldjeep]

39 minutes ago, Sparky450 said:

Can you tell me what grease. I have had two of these issues.  First one prop had been on for a number of years.  But again a sheared pin. I always run the brass pins. No stainless. I would rather a sheared key. 😃

Do not put grease on a taper.  It depeats the purpose of the taper. 

[oldjeep]

36 minutes ago, Sparky450 said:

I HAD a friend who lost his life to the old 2 part wheels with a ring.  He didn’t put a pry bar through the holes in the wheel, to catch the ring if it failed.😩

That sucks.  I had a set of those on an old willys  you needed to make sure you had a strap around them and a clamp chuck so you could be nowhere near them when airing up after a mount. 

[MadMan]

I think one of the main reasons that props end up loose, causing keys to shear, is that the prop isn't fully seated because of debris.  You have to clean the shaft and bore of the prop of any dirt or dingle-berries left from key.

I've even heard of guys using lapping compound to get the prop to fully seat. Of course you wash it all off before you install.

[Eagleboy99]

38 minutes ago, Slurpee said:

That happens anyways. And the prop pushing the boat tends to do the rest. Honestly take a sec to do the math on the forces on that prop pushing it up the shaft when we operate the boat. And that the service manual calls for tightening the prop but up after a few hours of use after install. None of us monkeys with a big ten inch wrench are gonna make that torque the engine does.

The grease helps reverse the process without threads like this. Just be reasonable about tightening the nut up. Cuz yeah a big enough monkey can break anything  

I’ve used a very little bit of the same grease I use on my hoist from BH USA. I’ve also used the same ball bearing grease I use on my bike. Phil’s I think it is. 

Sorry - simply wrong.  If you are familiar with Phil's, then you should know that some parts that are friction fit are NOT to be greased.

[Eagleboy99]

26 minutes ago, MLA said:

I disagree. If the nut is being used to seat the prop, you're doing it wrong. The nut is there to keep the prop from coming off. A fully seated prop will not move up the shaft any further with a nut at 32ftld.  

Nah - wrong.

[MLA]

45 minutes ago, Eagleboy99 said:

Nah - wrong.

LOL,  fair enough. 

[TallRedRider]

6 hours ago, Slurpee said:

 

Now after two PITA ridiculous prop pulls when I put a prop back on I use just the thinnest amount of water proof grease on the shaft.  Now those things come off pretty text book every time no matter what.

I think the guys at acme should probably know best...

Didn't anyone besides me get the directions from Acme in the box?  And read them?  

They say to use grease.  It is number 5 on these directions from the prop manufacturer.  I use a thin layer of bearing grease and my props are still stuck on tight, but do come off with a couple bangs of the hammer.  We should all take note of the 35 foot pounds of torque recommended as well.  

Edited September 17, 2018 by TallRedRider

[Eagleboy99]

46 minutes ago, TallRedRider said:

I think the guys at acme should probably know best...

Didn't anyone besides me get the directions from Acme in the box?  And read them?  

They say to use grease.  It is number 5 on these directions from the prop manufacturer.  I use a thin layer of bearing grease and my props are still stuck on tight, but do come off with a couple bangs of the hammer.  We should all take note of the 35 foot pounds of torque recommended as well.  

Here's the thing:  while a thin coat of grease might seem to make it better, anecdotal evidence suggests that removal is not  more easily facilitated.  And for the worse, a layer of grease, when the prop is moving up the shaft with forward propulsion will  actually climb further than it should, 35 ft. lbs notwithstanding.  I recall back in the day having massive arguments with Jobst Brandt (RIP!) who really knew this stuff.  Grease is good in only certain circumstances.  And a prop shaft ain't one of them. Tribology 101.

[onewake09]

2 hours ago, Eagleboy99 said:

Nah - wrong.

Care to explain this? I read for days that props move up the shaft during acceleration. So i tested it. Put a new prop on my boat(i wanted to try a different pitch anyway) and torqued nut to 35ft lbs. No grease, anti seize, nothing. Prop and shaft were cleaned with scotch brite ahead of time. I measured the distance from the end of the prop to the cutlass bearing with an inside micrometer. After running the boat for a few hours on the water I measured again and got the same measurement within a thousandth of an inch. I also measured from the end of the prop shaft to the face of the prop and got the same number. Is it possible for the shaft to slide up the shaft? Sure. With heat, a press, a sledge hammer. But not by the force of the prop turning. 

[MLA]

9 minutes ago, Eagleboy99 said:

anecdotal evidence suggests that removal is not  more easily facilitated

Im always open to new points of view, so where is this evidence. The use of grease or not, is certainly a worth while debate, but that not what im discussing. I dont see grease causing the prop to be over torqued. Please change my mind, but "nah - wrong" wont do it 

 

[Slurpee]

1 minute ago, onewake09 said:

Care to explain this? I read for days that props move up the shaft during acceleration. So i tested it. Put a new prop on my boat(i wanted to try a different pitch anyway) and torqued nut to 35ft lbs. No grease, anti seize, nothing. Prop and shaft were cleaned with scotch brite ahead of time. I measured the distance from the end of the prop to the cutlass bearing with an inside micrometer. After running the boat for a few hours on the water I measured again and got the same measurement within a thousandth of an inch. I also measured from the end of the prop shaft to the face of the prop and got the same number. Is it possible for the shaft to slide up the shaft? Sure. With heat, a press, a sledge hammer. But not by the force of the prop turning. 

You did all the right things to “properly seat” the prop. I’ve done a couple hack prop swaps on the river over the weekend before. And didn’t get the prop seated right. I always assumed there was a burr in the key or some crud on the shaft or user error. Later I saw about an 1/8” gap between the prop and nut. It was seated enough that the prop didn’t shear the key but it did move some. I always seat it on a clean shaft with a very thin layer of grease and tighten the nut down. Goes where it should and never moves after.  The key is to get it where it should be in the beginning I guess.

Anyways. My anecdotal evidence is that it is night and day different removing props that have been on the shaft a long time. Makes me feel better it’s in the instructions to. At the time I was thinking more about helping with removal and maybe it did something to help with galvanic corrosion.  And that’s the way my dad taught me which has some merit to me since he designed combat aircraft for a living. We could be wrong of course for some reason. 

[ahopkins22LSV]

Ummm isn’t the obvious answer...

[TallRedRider]

29 minutes ago, Eagleboy99 said:

Here's the thing:  while a thin coat of grease might seem to make it better, anecdotal evidence suggests that removal is not  more easily facilitated.  And for the worse, a layer of grease, when the prop is moving up the shaft with forward propulsion will  actually climb further than it should, 35 ft. lbs notwithstanding.  I recall back in the day having massive arguments with Jobst Brandt (RIP!) who really knew this stuff.  Grease is good in only certain circumstances.  And a prop shaft ain't one of them. Tribology 101.

I think you are arguing anecdotal evidence against book smarts.  I can only tell you what the guys who sell thousands of props per year recommend.  I have removed props that are greased and not greased, and I can say it is easier when they are greased.  Large amounts of anecdotal evidence usually results in solid proof.  

Reading what you are saying, I think you are insinuating that sliding up the shaft is a bad thing for the prop.  Perhaps it seats tighter with the grease and that is what actually facilitates an easier removal?  It is the differential in harmonic vibration that causes it to pop off, so hugging the shaft tighter might be the ticket.  And contrary to popular belief, 35 foot pounds is a lot of force, just put your finger between the prop and nut and see how much you can take.  (hint: you will measure it in inch pounds).  

 

 

[Eagleboy99]

You do not understand science/anecdotes.  That is ok.  Tighter seating is not a good thing.  Leads to increased wear etc.  Like I said Tribology 101.

[Eagleboy99]

35 minutes ago, Slurpee said:

You did all the right things to “properly seat” the prop. I’ve done a couple hack prop swaps on the river over the weekend before. And didn’t get the prop seated right. I always assumed there was a burr in the key or some crud on the shaft or user error. Later I saw about an 1/8” gap between the prop and nut. It was seated enough that the prop didn’t shear the key but it did move some. I always seat it on a clean shaft with a very thin layer of grease and tighten the nut down. Goes where it should and never moves after.  The key is to get it where it should be in the beginning I guess.

Anyways. My anecdotal evidence is that it is night and day different removing props that have been on the shaft a long time. Makes me feel better it’s in the instructions to. At the time I was thinking more about helping with removal and maybe it did something to help with galvanic corrosion.  And that’s the way my dad taught me which has some merit to me since he designed combat aircraft for a living. We could be wrong of course for some reason. 

Galvanic corrosion between Nibral and SS (shaft)?  I don't think so.  Nibral has a potential of about -50-100 mv SCE and typical (ignoring autentistic and alloys for simplification) SS is +150 vV SCE so unlikely to see any galvanic corrosion as a result of that combo.

But feel free to grease  it - the real key is torque and proper fitment.

 

 

[oldjeep]

15 hours ago, oldjeep said:

1) If you over tighten the prop puller it can deflect and make it even harder to get the prop off. 

2) Heat the prop hub up with a propane torch before you smack the puller

3) Hit the puller on the side of the C, not the bolt

 

I forgot #4

Hit it with your purse 😁

[nyryan2001]

Also you need to get the resonance vibration going..

3-5 hard hits with the hammer approx 1 second apart. 

[TallRedRider]

14 hours ago, Eagleboy99 said:

You do not understand science/anecdotes.  That is ok.  Tighter seating is not a good thing.  Leads to increased wear etc.  Like I said Tribology 101.

Thanks for not explaining it to me, since you are so smart.  I understand plenty about science.   Anecdotes are the multiple guys here with tons of boating experience who have shared what they found.  Interestingly, nobody has found grease to make things worse.  Science would be taking 500 props, and greasing half of them and seeing what happens, ideally while blinding the prop removal guy.   But since nobody will ever do that, we are left with expert opinion.  The guys at Acme and everyone who has an opinion on greasing the shaft disagrees with you.  All that you have is a THEORY.  So far, anecdotal evidence and expert opinion proves that greasing the shaft is the best way to go.  

I am going to get increased wear on the prop shaft from tighter seating?  That makes no sense whatsoever, as the parts don't move against one another.  

[Michigan boarder]

On 9/16/2018 at 10:21 PM, oldjeep said:

I forgot #4

Hit it with your purse 😁

#5: If that doesn't work ask your boyfriend to do it for you