Propeller Removal Preparation

[UNCIVILIZED]

If you didn’t have that pesky rudder so close to the shaft, I was going to tell you how to build an in place slide hammer, to get the prop free, but… Here's (something of) a Plan B:
It's a hypothetical solution, based on a very real tool, which is used for inserting & extracting strut bearings.

You’d need 3 stiff plates of the same size. Say between 4-6” square. And near the corner of each, is a hole big enough to allow 3/8”+/- all thread (rod) to pass through.

Two of these plates need to be cut in half, & also drilled for a hole big enough for the shaft to fit through, with just a bit of wiggle room. Plus, they need to be drilled & tapped, so that they can be bolted together. Such that the cuts in them wind up at 90 degrees to each other, when the two plates joined together.
Thus, when all of the machining is done, you wind up having “one” solid plate, that can be bolted together, in place, over the shaft. With a hole in it's center for said shaft. And also, with holes for the all thread near it's corners.

So, to operate said device. You’d first bolt the two split plates together, on the shaft, in front of the propeller. And then, put the all thread into the corners, with nuts on it’s ends.
After which, you’d put the 3rd plate at the end of the shaft, behind the propeller. With the all thread through it’s corner holes too, & with nuts on these ends as well.

Then, once you tighten things up finger tight, start slowly taking ½ turns on each nut with a wrench. In an X pattern on the plate. And, in theory at least, the pressure exerted by the plate behind the prop, should pull it free.

And probably the biggest catch as to whether or not such a setup would be viable on your boat, is determined by how much room there is on the shaft in front of the prop. That & I'm assuming that there's sufficient clearance between the aft end of the prop shaft & the rudder, to slip in the aft most plate in said contraption.

Well, unless I'm totally missing something, that is.

[fstbttms]

Originally Posted by Hudson Force

Guy, I'm glad you mentioned this problem. I've adjusted my puller to the proper span and rigged a bit of an adaptation to allow easy placement under water.



The rubber band and the tennis ball are opposing each other and I hope this will allow me to position the puller easily.



The dry land trial works well. The tennis ball can pop out once the puller is on the hub and the rubber band can remain until the ends snap in place without a problem. Thanks for helping me anticipate a problem. I'm sure to have enough challenges!

Bear in mind that there is going to be the the shaft and nut (which you do not want to remove, prior to loosening the prop) keeping the arm-ends from reaching the forward edge of the hub, so this dry run may not be entirely representative of your in-water reality. And know too, that it is the very rare prop that does not require significant hammer blows to the puller in order to be removed.

[Hudson Force]

Originally Posted by fstbttms

Bear in mind that there is going to be the the shaft and nut (which you do not want to remove, prior to loosening the prop) keeping the arm-ends from reaching the forward edge of the hub, so this dry run may not be entirely representative of your in-water reality. And know too, that it is the very rare prop that does not require significant hammer blows to the puller in order to be removed.

Thanks, fstbttms, I appreciate your advice. I have accounted for the space of the shaft and nuts aft of the prop and once the three bars of the puller are on the hub the tennis ball can be easily removed to allow more space. I expect some hammering to be required. I just need to prevent any damage to my other gear.

Although I'm an avid DIY fan, I will not hesitate to hire a diver such as yourself with the proper tools if my attempt fails. If nothing else I will scrub things clean and put my own zinc in place.

[fstbttms]

Originally Posted by Hudson Force

I have accounted for the space of the shaft and nuts aft of the prop and once the three bars of the puller are on the hub the tennis ball can be easily removed to allow more space.

What I'm saying is; in your mock-up, the tennis ball is sitting on the prop hub and the puller arms are easily reaching the front of the hub. This will not be the case in underwater, as the shaft and nut will likely add another inch or more to the distance the arms have to reach (with the tennis ball in place.) Perhaps cutting a hole in the ball, big enough for the nut to pass through would resolve that issue.

[fstbttms]

'Course, then how do you remove the tennis ball?

[Hudson Force]

This may be too trivial to explain, but the hub is 3" long and once the three puller arms are covering the first bit of these three inches, then the tennis ball serves no purpose as the rubber band keeps them on the hub and the ball can be removed. Actually, I'm more concerned with the clearance of the space between the end of the shaft and the rudder for the fit of the puller. All my questions will be answered in the water with no loss in the attempt. Thanks again.

[fstbttms]

Originally Posted by Hudson Force

This may be too trivial to explain, but the hub is 3" long and once the three puller arms are covering the first bit of these three inches, then the tennis ball serves no purpose as the rubber band keeps them on the hub and the ball can be removed.

Understood. Good luck.

[bletso]

I tried a three jaw puller and it didn't work. So, I made my own and tightened her down and under tension wacked the puller and the prop came right off. The prop was on so good that I needed 1/2 inch thick steel plate. (Welded two 1/4's together). 1/4 inch just deformed

[donradcliffe]

Plan B--primer cord.

[UNCIVILIZED]

Originally Posted by bletso

I tried a three jaw puller and it didn't work. So, I made my own and tightened her down and under tension wacked the puller and the prop came right off. The prop was on so good that I needed 1/2 inch thick steel plate. (Welded two 1/4's together). 1/4 inch just deformed

This is the kind of setup which I was describing. I'm surprised that it didn't get the prop to come off, sans hammer.

[Hudson Force]

Originally Posted by Hudson Force

.............. Actually, I'm more concerned with the clearance of the space between the end of the shaft and the rudder for the fit of the puller. All my questions will be answered in the water with no loss in the attempt. Thanks again.

As an update for my prop removal plan I'll report that my attempt was stymied by the lack of clearance to fit my puller due to the rudder. A local diver with a puller identical to the one FSTBTTMS recommended removed my prop in minutes. All went well until it was determined that the keyway slot in the new prop was smaller than the key and keyway slot in the shaft. Now I'm waiting for the return of my prop from machining at a nearby prop shop.

So, here I am in a slip with a "naked" shaft. I wasn't planning on going anywhere, but I feel vulnerable not being fit to get underway.

[fstbttms]

Originally Posted by Hudson Force

As an update for my prop removal plan I'll report that my attempt was stymied by the lack of clearance to fit my puller due to the rudder. A local diver with a puller identical to the one FSTBTTMS recommended removed my prop in minutes.

Yes, well, further proof that I am always right.

Originally Posted by Hudson Force

All went well until it was determined that the keyway slot in the new prop was smaller than the key and keyway slot in the shaft.

How much smaller?

[Hudson Force]

Originally Posted by fstbttms

.............. How much smaller?

I did not take the measurement before sending the key and prop to the shop, but the difference was significant. I did notice that the key way on my new prop was the proper fit for an old key that I had from an earlier 1" shaft that I had before repowering and changing to my current 1-1/4" shaft.

[fstbttms]

Originally Posted by Hudson Force

I did not take the measurement before sending the key and prop to the shop, but the difference was significant. I did notice that the key way on my new prop was the proper fit for an old key that I had from an earlier 1" shaft that I had before repowering and changing to my current 1-1/4" shaft.

Was wondering if maybe it wanted a step-key.

[Hudson Force]

Sure, the key as shown with adapting the two sizes would have been another solution, but I'm selecting the same configuration that I've been using since 2001. I've already sent the prop out to be machined to match the key way on my shaft. 'good of you to mention this other option though, thanks.

When I ordered my new prop I had detailed all the statistics as to diameter, pitch, shaft size, bore, etc. I failed to mention anything about the key way.