Stuck Prop

T

Tortuga

New member
OK, my oil change, lube (thanks again for those who responded to my grease post), and fuel filter maintenance all went swimmingly. So, I should have expected the last task to hold me up. My prop is stuck on the shaft. It was last off when the engine was new -- two years ago.

I didn't see anything in the archives -- so my question to all of you: how would you recommend removing a stuck prop?

I'm thinking PB Blaster and a modified flywheel puller. But, I'm hoping your combined wisdom will prevail and you'll have an easier solution!

Suggestions? Things to avoid?

Thanks!

Matt
 
Ice and a rubber hammer. get a couple of ice bags and wrap them around the prop for a 20 minute's . then hit it softly with a rubber hammer on the bottom edge. that should do it. if not go for the puller.
 
I have removed many that were stuck,just get someone to pull on it really hard while you hit the shaft with a hammer,make sure you put the nut even with the threads so you don't mess them up,the shock is what does the trick,usually only takes one hit,this is the same way to remove a steering wheel
 
I'm interested to hear about the ice as well!

If it were me I would hit it with PB Blaster, heat gun, and a rubber mallet then proceed to bigger guns from there if that did not work.

Good luck.
 
Thanks everyone -- I'll try ice first -- then if that doesn't work, heat. PB & a rubber mallet to show I'm serious. I'll let you know how it goes.

Matt
 
ice works the same as heat with out taking the chance or burning or warping something. its just a matter of changing the temp of the object. Heat expand and cold contracts but both will get the prop off. I first learned it from a old mechanic ( hell I think he was 40 at the time and I was 16, he seemed old them) while trying to get a ball joint the front end of my 62 chevy, miss that truck, and it worked really well.
 
Never had a stuck prop, Thank God.

Let's see, hot expands things and cold shrinks. An example is a wire, when it's heated the cross section increases and when it gets cold, the cross section decreases.

So, if I want to press a bearing into an aluminum case, where hitting it with a hammer is BAD, I stuff the bearing into the freezer and warm the case. If I want to take a gear off a shaft, I gently warm it with a torch and then pull. On my '63 Chevvy, I used heat to loosen the !@#$ steering joints off, and yes, it's still a great truck.

I don't know about propellers, but they are a hunk of metal and heating it would make it expand. Unless when it cools and shrinks, the cross section decreases and pulls away from the shaft. I also believe that heat loosens/breaks whatever bond holds those two things together, since it's supposed to be a slide fit.


I do know that hitting the end of the shaft is a good thing, but hitting it too hard isn't good for the bearings that support the shaft. I'd probably want to hit the propeller off, but then I've never had a stuck propeller.

Also, after I got the propeller off, I'd try to figure out how those grooves got stuck, since it's supposed to be a slide fit. Is it an aluminum vs stainless, or what?

Boris
 
Matt,

Expansion and contraction are something you can count on by changing the temperature of metal. It is easily measurable with a micrometer.

Go ahead and ice the whole lower unit as SC Tom recomends it may work fine. But if it doesn't, no problem you are halfway home. While everything is very cold, take a propane torch and warm up only the prop.

What you will have done is shrink all the metal with the chill and then expanded only the prop with the heat.

Get some good marine grease to put on the shaft before you reassemble it and you will not have this trouble again.

Dan
 
An outboard prop is made of three parts. The outer shell with the blades, the hub, and a rubber sleeve between the outer shell and the hub. The rubber sleeve is a slip clutch to mitigate gearcase damage if the prop strikes a solid object.

The hub is the part that is stuck on the prop shaft. Striking the prop blade (outer shell) area only results in that part bouncing back and forth due to the rubber sleeve between the hub and shell.

Heating the shell results in eventually damaging the rubber sleeve and not transferring much heat to the hub.

Some heat can be applied to the prop shaft/prop hub by carefully heating the propshaft end.

CAUTION: Too much heat on the shaft can damage the heat treating. The prop shaft is a very expensive part of the gearcase.

CAUTION: Striking the end of the prop shaft with a heavy hammer can damage the thrust bearing that is at the forward end of the prop shaft. A hard enough hammer blow could even crack the aluminum housing.

Prop shafts are to be coated with grease before installing the prop. Salt water getting between the prop hub and shaft causes corrosion and sticking of the hub.

Outboard shops usually have a prop puller that they may or may not rent/loan out.

Using a puller, it is possible to pull the outer shell completely off the hub/sleeve. The hub can then be heated or ground off the shaft. If the shell is not damaged, a prop shop can replace the hub/sleeve.

If any parts have to be sacrificed, it should be the prop. If the prop is SS, pulling the prop off the hub and re-hubbing is the best approach.

I have observed that the props most likely to seize on the shaft have aluminum hubs. [Aluminum hub on a SS shaft in salt water.....what were they thinking!!]

I recall one stuck aluminum prop that resisted all attempts at removal. I had to cut the outer shell off the hub and then grind one side of the hub down almost to the shaft before it released.

Larry H
Retired outboard mechanic.
 
Once you get it off, liberally coat the shaft with Triple Guage Grease and remove every year. It is amazing how well props come off when using that stuff.
 
What Matt said!

I fully recommend Triple Guard Grease, a product of BRP (makers of Johnson and Evinrude motors).

This stuff is great. It's a non-runny, water-resistant grease. It can be used to lube carb linkage, shift and throttle cables, steering cable ends, prop shafts and to coat metal parts. It's a good all-purpose grease.

(No, I don't have any BRP stock!)
 
You guys rock. The prop came off with no trouble. I didn't even get a chance to ice & heat it. I soaked the end of the shaft with PB Blaster and let it sit while I changed the lower unit gear oil. Then I was able to remove the thrust washer (is that what the large washer with the spline grooves is called) with just a touch of persuasion -- which allowed me to get even more PB Blaster in around the shaft. After another 20 minutes I used a rubber mallet to gently tap each of the blades in rotation until it came free.

I then cleaned and heavily greased the shaft with marine grease -- and will continue to do so every year.

The only problem is now I have twenty pounds of ice melting in my car...

Thanks again for all your help!

Matt
 
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