Cantaflex Coupling

[aread2]

I recently had a slight accident with my propshaft. I picked up a submerged mooring rope at my mooring and as I pulled away from the bank it neatly pulled my prop shaft out of the back end of the Centaflex coupling. Luckily the shaft stopped coming out of the stern gland when the propeller reached the rudder and the boat came to a halt before any serious damage could occur or the boat could sink.

 

My question is: How do I re-establish a secure coupling? Should I simply be able to loosen off all the bolts (8) at the end of the coupling nearest the prop and then slide the shaft back in before doing up the bolts again? It looks like some sort of Collet arrangement. Is there a specific torque I should be using to tighten up the bolts? Will I need to lock the gearbox end of the shaft to undo/do up the bolts?

 

Does anybody have an installation manual for this Centaflex coupling?

 

 

Edit : To clarify the question.

Edited September 27, 2008 by aread2

[Ike]

Bit hard to see from the photo but aren't there a few bolts (well machine screws) running at ninety degrees to the shaft? It's usually these that need loosening or removing and the ones running parallel to the shaft can be left as they are. The suggested torque depends on the size and is 10Nm for M6, 25Nm for M8, 50Nm for M10 and 85Nm for M12. The bolts should be lightly greased before assembly although there may be enough already on and I'd be cautious about using too much as just about any common grease is going to be bad for the rubber.

Edited September 28, 2008 by Ike

[Timleech]

My question is: How do I re-establish a secure coupling? Should I simply be able to loosen off all the bolts (8) at the end of the coupling nearest the prop and then slide the shaft back in before doing up the bolts again? It looks like some sort of Collet arrangement. Is there a specific torque I should be using to tighten up the bolts? Will I need to lock the gearbox end of the shaft to undo/do up the bolts?

 

Does anybody have an installation manual for this Centaflex coupling?

 

 

Edit : To clarify the question.

 

Yes, slacken those 8 bolts/screws, remove as much grease etc as you can from the shaft and collet. Reinsert the shaft, tighten the screws in rotation and keep on tightening them in rotation until they will tighten no more. Go for a trip and tighten them again. I don't know what the recommended torque is, but just as important is to go round them several times and then once more for luck.

 

Tim

[aread2]

There are no machine screws at 90 degrees to the shaft. In the picture the end of the shaft is just inside the lip of the opening in the end of the Centaflex. The grease on the shaft covers the part that is normally inside the coupling. I think the receiving end of the coupling is a Collet chuck that grips the end of the shaft. There are eight large nuts on the face of the collet and my guess is that these are used for tightening it. There are also four holes for machine screw around the coupling (one is clearly visible in the picture) but they are blind holes and none have screws in them. I am guessing that the empty holes are for holding the coupling still while the collet is tightened. I'd just like to know if anybody has installation instructions for the Centaflex-M coupling so I can confirm my suspicions and find recommended torque setting for the collet bolts.

[Eeyore]

I recently had a slight accident with my propshaft. I picked up a submerged mooring rope at my mooring and as I pulled away from the bank it neatly pulled my prop shaft out of the back end of the Centaflex coupling. Luckily the shaft stopped coming out of the stern gland when the propeller reached the rudder and the boat came to a halt before any serious damage could occur or the boat could sink.

 

My question is: How do I re-establish a secure coupling? Should I simply be able to loosen off all the bolts (8) at the end of the coupling nearest the prop and then slide the shaft back in before doing up the bolts again? It looks like some sort of Collet arrangement. Is there a specific torque I should be using to tighten up the bolts? Will I need to lock the gearbox end of the shaft to undo/do up the bolts?

 

Does anybody have an installation manual for this Centaflex coupling?

 

 

Edit : To clarify the question.

Refit as per Tims instructions.

Torque setting are on the middle pages of http://www.centa.info/data/products/31/int...marine03-05.pdf (please cut and paste into your browser: I cann't get the link to work this morning)

You need to slacken the stern gland to make it easier to push the shaft back into place.

The shaft should be a smooth slidding fit into the coupling.

If its tight you may have some burring on the shaft; or your engine mounts may need a little adjustment.

Steve

Edited September 28, 2008 by Eeyore

[aread2]

Thanks for all the advice. I have managed to put the prop shaft back in the coupling and clamped it together again.