Shaft Zinc Placement

Sep 25, 2008
436
Catalina 30 MKIII Varuna Boat Club
Hi all,
Getting my C30 ready for launching in a few weeks and a thought came to mind that I never had in the 15 odd years of owning my Cat30's. I have always placed two shaft zincs on the shaft between the engine side and the strut. I noticed that the space on the shaft between the prop and strut is just the right size to mount a standard shaft zinc....so, I did and I mounted the second one about 8" up from the strut. Once mounted, the lower zinc has about 1/16" clearance on the prop side as well as the strut side.
I was wondering if there is any reason for not doing so?
 
Feb 21, 2013
3,796
Hunter 46 Point Richmond, CA
I install 2 zincs on the middle of the shaft, one about 8 inches forward of the strut and a second one about 6 inches forward of the first zince as shown in the attached photo. I understand this location on the middle of the shaft avoids reducing water flow into the cutlass bearing and does not interfer with the shaft log.
 

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Jan 7, 2011
2,928
Oday 322 East Chicago, IN
I install 2 zincs on the middle of the shaft, one about 8 inches forward of the strut and a second one about 6 inches forward of the first zince as shown in the attached photo. I understand this location on the middle of the shaft avoids reducing water flow into the cutlass bearing and does not interfer with the shaft log.
That is how I do it...
 
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Mar 6, 2008
694
Catalina 1999 C36 MKII #1787 Coyote Point Marina, CA.
When the propeller is moving the vessel forward and backward it also moves the engine back and forth. The movement is more than 1/16", you can see this where the shaft comes out of the stuffing box. Since you have only 1/16" of space it is sure to rub against the cutlass when shifting forward and backward.
Haro
 
Sep 25, 2008
436
Catalina 30 MKIII Varuna Boat Club
Point taken and appreciated. It's always a good idea to ask before implementing a "good idea". Thank you.
When the propeller is moving the vessel forward and backward it also moves the engine back and forth. The movement is more than 1/16", you can see this where the shaft comes out of the stuffing box. Since you have only 1/16" of space it is sure to rub against the cutlass when shifting forward and backward.
Haro
It's always a good idea to ask, before implementing a "good idea". Thank you.
 
Oct 22, 2014
16,148
CAL 35 Cruiser moored EVERETT WA
it is sure to rub against the cutlass when shifting forward and backward.
:plus:Very true. Now adding to the rubbing is the possibility that you could break the strut. If enough force is placed against it as you change gears. Think about the shaft moving through the cutlas bearing. The zinc (which you secured tightly agains the shaft) slamming into the strut as you shift gears.

Maybe it will not happen. I would not want to take a chance.
 
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