Catalina 34

General Activities => Main Message Board => Topic started by: fulvio on May 25, 2013, 01:01:33 PM

Title: centering ring on bullflex shaft coupling
Post by: fulvio on May 25, 2013, 01:01:33 PM
I just received a new Bullflex flexible shaft coupling, so I'm about to do this upgrade.  The manual talks about a "centering ring" that needs to be removed before installation if the shaft has two rigid bearings.  I quote:

QuoteWhere the propeller shaft is supported by one rigid bearing only, the Bullflex coupling - with the centering ring installed - will function as a flexible ball joint.
When the propeller shaft is installed rigidly which means to say - supported by two (or more) non-flexible bearings - the propeller shaft should not be affected by engine movements.  Therefore remove the centering ring in such an installation.

The picture illustrating the first case (one rigid bearing only) looks a lot like the setup on the C34 - cutlass bearing and packing gland.  The reason I feel a bit uncertain, and hence my question, is that the stuffing box/packing gland looks very much like a rigid bearing to me.  So I don't really know which case applies to the C34.

Have others who installed the Bullflex removed the centering ring, or left it in place?

Thanks!
Title: Re: centering ring on bullflex shaft coupling
Post by: Ron Hill on May 25, 2013, 03:25:50 PM
fulvio : Why don't you call Vetus (888)468-3887 and ask them your question. 

I don't believe that a C34 has a "centering ring".  Your shaft goes direct from the packing gland to the transmission in about one ft.

A thought
Title: Re: centering ring on bullflex shaft coupling
Post by: fulvio on May 25, 2013, 04:16:16 PM
Ron,
Good idea, I will call Vetus.
The centering ring is part of the Bullflex assembly, between the hub and the flange.  It's not on the C34.
What the manual says is that depending on whether the boat has one rigid bearing on the shaft only, or two (or more), that ring must be left in the coupling, or removed.
I just thought that others who performed this upgrade would have come across this issue before me.
Thanks!