How To Remove Shaft Coupling?

[kwmeyer13]

Hello all, I am looking for some direction on how to remove the coupling that connects the propeller shaft to the transmission. The boat is a 2004 Pilothouse Sedan with twin 240 horse power 4LHA-ST yanmars with ZF Hurth marine transmissions. I removed the 4 bolts and separated the shaft w/ coupling from the transmission, the removed the 2 allen head set screws so I could removed the nut that is attached to the rear end of the shaft inside the coupling. So my question is, what do I do next to get the couple off? Do I need some sort of prop type puller? The coupling seems to be on really tight. I don't want to bend anything. Any advice on this would be much appreciated. I need to get the coupling off so I can side a replacement Tides Dripless seal onto the shaft. Thanks

 

[Brooksie]

Sounds like you have a coupling that is tapered just like the propeller end. I have one too, they are a great idea because it makes the shaft reversable in case of damage at the stuffing box or cutlass bearing/s. That said, there is a puller that came with mine (pusher actually) that threads into the fine threads inside the bore where the nut came out of. Tightening this down pushes on the end of the shaft and pops it off its' taper on the shaft.
Do you see the threads I refer to?

 

[O C Diver]

A picture would help.

If you have a socket set, you can put a small socket between the coupling on the shaft and the one on the transmission, then squeeze them together with 2 of the coupling bolts. Then repeat the process with a longer socket. This should push the shaft out of the coupling. Longer bolts may be necessary and will make the process faster.

Ted

 

[kwmeyer13]

Not able to post a picture as I don't have one and the boat is yard right now. In the center of the shaft there seems to be a divot or hole if I remember correctly. I had thought about using a socket or something on between the shaft end and the transmission and tightening down on the coupling bolts but I was afraid of bending and or damaging something. That is why I thought about the puller. Just need to make sure it can fit into the space between the transmission and shaft.

 

[O C Diver]

The divot as you refer to it is called a center point. It's used in the process of manufacturing the shaft. Won't be effected by pushing the shaft out with a socket.

Ted

 

[kwmeyer13]

Do I need to worry about warping/bending the coupling or damaging the transmission?

 

[LarryM]

Do I need to worry about warping/bending the coupling or damaging the transmission?

Compass Marine has this How-To article covering the removal of the coupling from the shaft. It is worth a read.

 

[kwmeyer13]

Just wanted to say thanks for the responses. Went down to the boat this morning after reading Compass marine article and very carefully used the socket trick. Just one or two gentle turns with a wrench and off popped the coupler. I slipped on the spare seal made a template with a small block of wood and bolted it all back together and into the water went the boat and not a drip to be found.

 

[jleonard]

Not able to post a picture as I don't have one and the boat is yard right now. In the center of the shaft there seems to be a divot or hole if I remember correctly. I had thought about using a socket or something on between the shaft end and the transmission and tightening down on the coupling bolts but I was afraid of bending and or damaging something. That is why I thought about the puller. Just need to make sure it can fit into the space between the transmission and shaft.

Like already stated, I also have used a socket and tightened the bolts to act as a puller. Tighten evenly and it won't bend or break anything.