Prop key way is sheered

I am trying to remove the prop on my 97 nautique. I acme prop puller snapped in two. So I took a look at the back of the prop and I can see the two key ways (shaft and prop key way) are not aligned. So the brass key sheered when the prop got hit and I'm sure the bronze key (pieces) are what has the prop jammed. What is the best path? Cut the prop along the keyway (carefully) or use an oxy acet torch and heat the prop while the puller is keeping tension on it? I'm experienced with a torch and controlling heat. I was planning on heating two opposing areas on the prop base very quickly while keeping some water on the cutlas bearing so heat doesn't travel up the shaft. The tension from the puller will let me know when it's done (pop) and I can cool everything quickly. So what are the votes? cut or cook?
Thanks,
Adam

I checked runout on the shaft and it looks fine. i was told anything under .035" is good. i didn't measure it with a mic but put a piece of wood between the shaft and hull and turned the shaft. I could not see any runout with the naked eye at several points. It will be a matter of vibration feel once in the water. Fingers crossed. New boat so yeah for new purchases. Ughh.

Bummer, especially with the new boat.
Sorry, not much help from me. Have not had the opportunity to deal with a prop and sheered/jammed key.
Hang on. Some of the experts will be here to help you out. They are typically a little slow to respond during boating season!

Could have sworn max allowable shaft runout was .003, Pete will know for sure.

A hard enough prop hit to shear the key and you think the shaft is ok? I have my doubts. I think its time to break out the sawzall (and your wallet).

Duane- I have a four blade so the three bolt configuration puller won't work?
Adam

As Tim mentioned, you may need to get your sawzall and perform shaft surgery. If you hit your prop hard enough to shear the key, I'm betting that you have other issues.

If you do cut the old shaft, you may want to consider A.R.E. shaft replacement as it will make your life easier in the future. (about $400 with discount)

I would give Vince a call at www.skidim.com and get his input.

At a minimum, the drive-shaft needs to be removed and accurately measured (I would go to a local machine shop). The strut may also be bent. Good time to do a shaft alignment.

JQ

BaccoBouncer wrote: Duane- I have a four blade so the three bolt configuration puller won't work? Adam

Below the pic it states will work with 3 or 4 blade.
I always use heat to remove my props. Follow instructions in above post and do make sure to have the nut on a thread or two, when they pop it scares the crap out of ya the first couple times.

Tension lots of heat and a hammer (since prop is junk) you may get lucky and not have to cut the shaft. As Tim said a hard hit like that is likely to have bent the shaft. Check run-out on the end to insure it's not bent after the strut which is most likely where it would be bent.

TRBenj wrote: Could have sworn max allowable shaft runout was .003, Pete will know for sure. A hard enough prop hit to shear the key and you think the shaft is ok? I have my doubts. I think its time to break out the sawzall (and your wallet).

I confirm that the .003" is an ideal not to exceed.
Adam,
Unless I missed it, I didn't read what caused the damage. Off hand, you must have hit something shearing the key because the prop wasn't lapped to the prop shaft? If so and considering the run out you see by eye, I too would say the shat is gone. As mentioned, the ARE shaft system is the way to go. As Tim mentioned, it may be time for the Sawsall! Do check your strut as well. BTW, you would never get the prop off in that condition with a "C" clamp type puller.

Here's the $10 prop puller that Duane copied.

Get a small punch or drift and tap the key stock back and get it to move, then apply puller pressure to the prop. Keep tapping it back as you pull it off. I saved a buddies shaft on Master Craft last year doing exactly this.

Drop the rudder and pull the whole thing out in one piece. Drop it off at the prop shop with wink and say "fix it". Those guys have man size tools and know how to use them. Your gonna have to wrestle the coupling sooner or later, might as well try to save the shaft and prop.

If tapping the key out does not work I have had luck by tensioning the prop puller as tight as I thought was safe and then taking a open end wrench just large enough to go over the prop shaft with no drag. 1 1/16 over the 1" shaft worked for me. With the wrench up tight against the prop, prop puller attached I hit it hard on the wrench from the engine side with a 2lb ball pen hammer. One good hit popped it for me.
As mentioned it is a good idea to have a nut on the shaft as you do this. I had parts fly. Not good for trailer paint but it came off and the prop was already bad.
If it is really stuck bad I think I would use my sawsall and cut the prop in two places opposite sides of the shaft. Cut down as close to the shaft as is safe. Bronze will cut easy while the stainless shaft will cut hard.   With the prop cut nearly through it will lose tension.
If your shaft is close to good you may get a machine shop to straighten it for you.
I used to know a guy that could get them back to perfect.
With that said when I needed to change mine I stepped up as advised and bought the ARE shaft they are really nice and easy to work with.

Cutting both is a lot easier on a machine tool with coated carbide. They're both nasty and if you let them get hot they'll work harden and stare back at you laughing at your puny hacksaw blade.

I've never seen a sheered key. That would take some serious energy, enough to wipe out the prop and rudder. If you can't cut the shaft push it out of the coupler.

Start fresh in the boat and make that lamp.

Hollywood wrote: I've never seen a sheered key. That would take some serious energy, enough to wipe out the prop and rudder. .

I'd have to say the chances are high that the prop wasn't lapped on the shaft and not firmly attached so it was being driven by the key only.

DayTony wrote: I would def say the nut may have been loose or there was not a proper lap as well. .

8122pbrainard wrote: our props are held on by a close fitting taper. According to one of the prop manufacturers, 70% of the torque is said to be transmitted through this fit and the rest is the key/keyway. I personally feel it's 100% because the taper fit shouldn't slip at all. I've seen some pretty sloppy keys with 0 evidence that any force has been applied to them.

8122pbrainard wrote: Keep in mind that a taper is the only thing that holds a drill chuck in a drill press spindle!! Also, take note of Eric's comment that many trans components are held together with tapers only. No nuts!!! Think about why a puller is needed to get a prop off!!

I've seen boats come in with the nut missing and the prop still on. Sure is evidence that a properly fit prop on the shaft works. The nut's purpose is to seat the prop on it's taper.