Best rust solvent

[Bowdrie]

Sorry if you thought my comment was spiteful.
I should have placed an emoji after it.

Ok, If it's what I think it is, (I have a similar drive, it holds a sprocket on the steering shaft to use a rotary auto-pilot drive,) those three holes are NOT for a puller.
Those pulleys have a tapered bore, a matching split tapered hub that fits the shaft goes into the large tapered bore of the pulley.
Two of the holes use machine crews to draw together the two parts, (hub/pulley,) to lock the arrangement to the shaft.
The third hole uses a machine screw to "unlock" the two parts, with the locking screws removed a setscrew is threaded into the third hole to force the two parts apart.
A good clean-up on the assembly should reveal how it goes together.
Hint; sometimes Allen head screws are used.
It's an ingenious design, no hammering or pressing should be needed for either assembly or disassembly.
When reassembly is done coat all parts of the tapers with a good anti-seize, and pack those three holes with anti-seize before using the screws to lock everything together.
This pic should give you an idea how they work.
https://www.motion.com/products/sku/00226251

[Tillikum]

From the photograph you are lucky enough to have a "taper-lock" hub there. That is a tapered, split (blue arrow) collar which slides into the outer tapered flange which forms the exterior portion of the pulley, and is retained by several bolts. (yellow arrows) The split can be clearly seen in your photos as can the ends of the bolts.

Pressing, hammering etc. is therefore not necessary and if you hammer it you will FUBAR the shaft for certain. Pressing with too much force will bend the shaft or also mushroom it. Don't do either, a taper-lock is designed to GRIP by compression and that is what it does. As the bolts are tightened the taper is pulled down into the cone and you won't be taking it out anyway except the right way.

One of the beauties of this system is that the tapered hub if well-matched in diameter to the shaft, will grip it tightly around its circumference thereby spreading out the rotational load. The conventional and simple straight shaft into a straight hole puts all the driving thrust onto the key and the key-way so that when overloaded, the key shears or the shaft does. A taper-lock with a key will definitely not give way before the shaft shears. The happy medium is to have no key, but only the taper-lock, which if properly adjusted will hold well enough for drive purposes, but spin on the shaft if over-loaded, but I digress...

The pulley shows heavy previous rust pitting, so you needn't worry about the paint. Once you get it apart, glass-bead it and phosphate it (see a gunsmith or engine rebuilder) and then paint or oil.

The procedure for getting taper-locks off is to undo the two or three bolts and put them into the currently empty holes which are designed to pull the cone out of the collar.

If the bolts will not turn with reasonable force, they are no doubt rusted in place so you will need to soak those with a good quality penetrating fluid from both ends, repeatedly over the course of a week or so.

You could apply a reasonable amount of heat to the heat to the heads of the bolts and given enough time, the heat will migrate down the bolt shanks and threads. However, if the pulley and shaft are cold, they will simply absorb the heat from the bolts, so put it in a junk toaster oven at say 300° for a couple of hours first. Hot enough to help, but not hot enough to damage the heat-treatment of the shaft or pulley.

The purpose of heat is to expand the bolt in it's hole and thereby crush the rust and crud which is locking the bolt in place, as well as hopefully break the friction bond which every tight fastening has. Having been compressed by the heat expansion, once everything has cooled there is hopefully a minute gap into which a thin penetrating oil can...penetrate.

When you put your six point wrench or socket onto the bold heads (not a crescent wrench, vise-grip, pliers or any other such) watch the opposite end of the bolt as you gradually apply more and more force to the wrench. If you see no movement on the end of the bolt opposite the wrench, but you feel ANY rotation of the head of the bolt, immediately stop as you are in the process of tearing the head off the bolt.

It's good practice to gradually increase the force on the wrench and then try going back clockwise, and the opposite and so on. This "rocking" can help to break the bond also and gives less risk of twisting off the head of the bolt. It's analagous to the process of hand-tapping where for every small rotation one reverses counter-clockwise until the chip formed by the clockwise rotation of the tap is felt to "break". The difference in rotational resistance is easily felt; likewise with bolts where they are rusty or very dirty small movements gradually compress and release the material jamming the threads.

As a last resort you can indeed tear the heads off all the bolts and then carefully drive the collar out of the flange with a punch or a suitable collar in a press, but the you will likely need to buy a new flange as you probably won't get the stubs of the bolts out of it.

Once you have the collar out of the flange the blade of a large screwdriver can be gently tapped into the slot of the flange, loosening it on the shaft and hopefully allowing the shaft to almost fall out.

If the bolts were a struggle to get out, replace them with some grade 5 or 8 replacement and use plenty of anti-sieze compound on the threads when assembling. Make sure the shaft, shaft hole and collar/flange have only the lightest coating of oil or anti-seize when assembling. Just enough to keep them from rusting together in future.

These things may not matter so much, but when at sea with no hardware/chandlery at hand, one needs every trick there is, unless one is smart enough to bring plenty of spares.

Amen.


PS: looking a bit more at your photo it appears someone has "adapted" a tapered collar of the wrong size to your flange/pulley. Notice how the three holes marked with the white arrows, which is where the bolts are inserted to remove the collar from the flange, have almost no clearance? You'll never get the bolt heads in there and then get a wrench or socket on top. You'll need three pieces of steel pipe or tube with a wall thickness as close as you can get to the distance between the outside of the bolt holes and inside wall of the flange. The internal diameter should be as close to the diameter of the bolts as you can get. 3/8" Schedule 60 or maybe 80 pipe or DOM tubing would be best. With such sleeves over each bolt, made long enough to bring the bolt heads higher than the top of your flange, you should be able to pull the collar out, all else being equal. Use Grade 5 or 8 bolts is my advice.

Alternatively, if there is nothing on the opposite end of the shaft as shown in your photo, you could invert it in a press or on your bench and use a piece of hopefully heavy wall pipe or tube slid over the shaft to press or knock the taper out. The pipe or tube should be longer than the shaft by a inch or two at least so that you don't accidentally damage the end of the shaft when the collar drops down.

Buy the correct collar for your flange and shaft diameters before reassembly.

[Icarus]

There seems to be a taper lock holding the gear to the shaft... Those 3 holes have fasteners in it?
The 4th hole might be for extraction...

[flightlead404]

Originally Posted by wholybee

For sure, a press. I wouldn't even attempt any other way. There are many other rebuilding tasks that would need one, from rebuilding a water pump">raw water pump, a gearbox, etc. So, if you have the space, they aren't very expensive.

If you don't have the space or don't want one, pressing something like that is probably only $20 at a typical machine shop, and would take 30 seconds.

https://www.harborfreight.com/12-ton...ess-70604.html

I have built my own press using a 40 ton hydraulic jack from the marine aisle at harbor freight and some steel beams.

You could use a small bottle jack and possibly lumber or something from Home Depot if you don't need that level of force.

If you do this, be very careful. If that thing comes flying out under high force it could be dangerous.

[RaymondR]

Boiling it in light oil and leaving it in until it cools may help.