Prop Coupler stuck onto Prop Shaft - HELP!!!

[adjo]

"You aren’t suppose to reuse the old flange do to rusting of the ID of the old coupling, so do your self a big favor and buy a split bolt coupling for the same diameter of the prop shaft. It does not need set screws or a key way, but can be ordered with a key way cut into it and is self aligning. My split coupling has been in service for two years with no problems."


You can use the old coupling many times over.
It should not rust internally if correctly fitted to the shaft coated with grease. It shouldn't rust externally either if correctly maintained but that's not always easy. Wrapping in Denzo tape (or equivalent) is an option.

[kenbo]

Originally Posted by Minggat

#1. This is NORMAL.
#2. NO FLAMES. NO HAMMERS.

Backing plate or trans output flange. 4 all threads 12 nuts. Spacer(s) sufficient to give you the travel you need. You might go buy nuts to stack together to do the job. Stick them together with blue tape. Press the coupler off the shaft evenly.

When you get them both in hand, (assuming you’re on the hard) take them to a machine shop to have them checked and surfaced if necessary. The face of the coupler needs to be mated with the shaft. The machinists will know.

Don’t screw with this. You can induce the effect of a bent shaft, spinning a few thousand RPM hours on end for years, or until it tells you that you got it wrong. $$$

+1 If you salvage the old 1/2 coupler it absolutely will need to be face fit on the shaft to be certain of alignment. But to do that the shaft has to be pulled too.

[kmacdonald]

Using the socket method risks breaking the flanges on the gear. Expensive mistake! It's not unusual to cut the shaft and replace it with a new one and new coupler. You could also raise the engine and pull the shaft out from inside the boat. Then use a press to remove the coupling. DO NOT bang on anything connected to the gear. It will flat spot the bearings in it.

[Sailmonkey]

I use one of these, you’ll also need a new coupling.




https://www.deepblueyachtsupply.com/...0aAmkUEALw_wcB

[LouN]

I just did this job. Used puller identified by Sailmonkey, but from a different source. Tried the socket route without success this time. Went with puller when I became concern with transmission flange. Had to shorten the stern tube to get room to use puller. I reused my coupler as it was in good shape. But I got a 5-foot shaft with the only other fixed point being the cutless bearing.

[dfelsent]

I’ve used the stack of washers/ nut/socket with great success. Easy peasy. Never felt close to damaging shaft of transmission flange. Definitely check for set screws.
As long as you are there, if you have the time and energy, pull the prop and shaft.
Take the shaft, prop, and coupler to your local propellor shop. For short money they will make sure everything is straight, and that they all have an excellent fit to each other, any that the flange is perpendicular to the shaft.
That can help with vibration you didn’t know you had.
And if that’s not enough of a detour, replace the cutless bearing and realign the engine.
I had to take another detour and dig out and re-bed the strut but that’s another tale.

But seriously my understanding is that having just the shaft and flange done together can be a win.

[Dougtiff]

Don't forget to apply Lithium grease when you put the coupler back on,if it had been greased before you would not be having this problem, grease ANY metal fitting tight.

[boatnerd]

Regardless of how you remove it there's good chance you'll need to source a new coupler. Skip the middleman and order direct from
Buck Algonquin ~

https://www.hydrasearchrecreational....g-accessories/

[deblen]

https://marinehowto.com/new-prop-shaft/

[dfelsent]

If you are in the North East of the US.
www.hhprop.com

[Perfect Ride]

Ditto on recommendation on using a puller.

FYI on penetration oils: CorrosionX HD
also: https://www.carcareninja.com/best-pe...g-oil-reviews/

[Spring-Fever]

SUCCESS! Thanks to all for your comments! This coupler did NOT break free easily. Turns out CATALINA DIRECT sells a puller just for this job ($47) https://www.catalinadirect.com/shop-...versal-diesel/

However, I made one at home. It worked better than the socket as wedge, because i think the socket I used might have been catching the slot-key, and not pushing the prop out cleanly. The single 1/2" bolt down the middle of my homemade "puller" was straight down the middle of the prop - and ultimately got the job done. Still needed a lot of heat and PB Blaster, but it finally broke free. I'm happy that I was able to salvage and clean the old coupler. Turns out there are clam-shell designed couplers, etc (and I was very close to trying to cut off just the existing coupler - but that would have opened another can of worms.).

Great news was that it made it easy to replace the stuffing box packing gland, which it clearly needed. The Catalina has such short spacing between the stuffing and the coupler, I'm not sure I could have replaced the packing gland without the whole thing taken apart!


All's well that ends well, I guess. This job was a nightmare.

[AJA]

Had that problem years ago when repowering; Interesting story actually - we were coming into Wickford harbor (RI), under engine, turning to port approaching the Wickford shipyard when a horrible banging sound came from the engine compartment. Turns out the old atomic 4 had thrown a rod. It was just July 2nd, and it appeared my season was over in terms of any motorsailing ( A prerequisite going out to Block Island if you want to make the 18 miles in less than 6 hours - the wind being perpetually from the SW until you want to go back to Newport when it will shift for the duration of the sail to the NNE). At any rate, we had the momentum - luckily enough - to coast into an empty slip. And once tied up I noticed an Atomic 4 sitting next to the crane, not 200 ft from me. Turns out a fellow was switching from gas to diesel, and I was able to purchase his old A4 for about $400 ( worked well for years after, BTW).
It was in changing the engines out that I was forced to remove the shaft as the cutlass was in need of replacement anyway. Same problem- I could not get the coupling off the shaft. My solution was to cut the shaft free with a hacksaw, and buy a new one.
Maybe a bit of overkill, but we were back in Newport in only 3 days time.

[sailorladd]

How about buying a couple of thin cutting blades for a 5 inch angle grinder and place large rags around the bilge areas where you dont want sparks or dust to fly, and then cautiously slice the coupling along the shaft, then using one or two long flat screwdrivers, hammer into this crack (even if you have not completely cut through the coupler...)
This would certainly break the rust hold and you should have it off in no time..

[col50]

Originally Posted by sailorladd

How about buying a couple of thin cutting blades for a 5 inch angle grinder and place large rags around the bilge areas where you dont want sparks or dust to fly, and then cautiously slice the coupling along the shaft, then using one or two long flat screwdrivers, hammer into this crack (even if you have not completely cut through the coupler...)
This would certainly break the rust hold and you should have it off in no time..

Not a bad idea, but make sure the rags are wet.