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post #12 of Old 01-08-2007
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Fstbttms's Avatar
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Location: Under a boat, in a marina, in the San Francisco Bay
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OK, here is a blow-by-blow description of how to pull your prop from someone who does it for a living. It is very unlikely that you will be able to remove the prop without a prop puller. I wouldn't even bother trying to do it without one.

Tools you will need:
Prop puller (a gear puller will be difficult to use by yourself underwater)
Pipe wrench
Flathead screwdriver
3' or 4' length of lumber (preferably 2"X2")
Small sledge hammer (optional)

1.- Pry up the ends of the cotter pin with the screwdriver. Use the pliers to pull the pin from the shaft.
2.- Place the 2X2 between the strut and rudder. This will immobilize the prop as you use the pipe wrench to remove the prop nut(s) from the shaft. Leave one nut on the the shaft near the end of the threads as this will keep the prop from falling off the shaft when it pops free.
3.- Place the puller on the shaft. Remember that you want the pulling force to be as nearly aligned with the shaft as possible. Any angle in the pull will tend to cause the prop to bind as it comes off. Snug the puller up against the end of the shaft and the forward end of the prop hub. It just needs to be snug, this is not where the pulling force comes from.
4.- Begin tightening the puller. Do not over-tighten as it is possible to break the puller. If the prop does not come off immediately, bang on the aft end of the puller with the pipe wrench or hammer. If this does not free the prop, remove the puller and rotate the prop a bit and reset the puller in a new spot. Repeat instructions 3 and 4 until the prop comes loose. Pressure, vibration and persistance are key here. Keep the pressure on and bang the hell out of the puller. All props will come off, but some just take more effort.
5.- The prop will likely pop loose quite forcibly. Once it does, rotate it so that the shaft key is on top of the shaft. Remove the prop nut and slide the prop off the shaft. Be sure to see if the key has remained in the keyway in the shaft. It may want to stick inside the prop. Either way, be aware of it as you will need to use it with the new prop.
6.- Put the key back into the keyway on the shaft (if it came out during removal.)
7.- Slide the new prop onto the shaft. Force it up hard enough that it does not slide back down.
8.- Re-install the larger of the two prop nuts. Hand tight is fine.
9.- Place the 2X2 between the strut and rudder.
10.- Using the pipe wrench, tighten the main nut as tight as you can get it. Repeat this process with the jam nut (if you have a 2-nut system.)
11.- Put a new cotter pin in the shaft and bend the ends over with the pliers. You're done!

I generally line all my tools up on the edge of the dock for easy and safe access. The puller I attach to the prop shaft with a short lanyard as it will fall away from the shaft when the prop comes loose. You can do the same with the wrench or hammer to give your arm a rest in case you're doing a lot of pounding. If the distance between your strut and rudder are too great for your 2X2 to span, you can wedge the 2X2 up against the shaft forward of the strut on the opposite side of the strut where the wood will be lodged.

Good luck!

Last edited by Fstbttms; 01-08-2007 at 05:49 PM.
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