26 general marine shaft zinc

rusty12

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I have a 26 gm and was wondering if I should have a zinc on the shaft. I only have 1 3/4 of shaft space between the end of the shaft key and cutlass. H and h stated that you need at least 3/16 for waterflow for the bearing....most collars at 1 1/2 which would leave me 3/16. Will I have an issue with cavitation with that setup or would i be better with a prop nut zinc?
 

Eslang

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I have a 26 gm and was wondering if I should have a zinc on the shaft. I only have 1 3/4 of shaft space between the end of the shaft key and cutlass. H and h stated that you need at least 3/16 for waterflow for the bearing....most collars at 1 1/2 which would leave me 3/16. Will I have an issue with cavitation with that setup or would i be better with a prop nut zinc?
Yes it will cavitate. My friend has a 26 and we have to turn a zinc down on a lathe to make it work. If we put a standard zinc on it shakes so bad you would think the gear was bad.
 

F/V First Team

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it is a copper strap with a conductor on the end that rides on the shaft. bend it so that it is just in contact with the shaft that way its not scoring the shaft. a bonding wire is hooked to the strap and grounded to the rest of the system. easy peasy. just mount it on a block somewhere down in the bilge out of the way.
 

BillD

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it is a copper strap with a conductor on the end that rides on the shaft. bend it so that it is just in contact with the shaft that way its not scoring the shaft. a bonding wire is hooked to the strap and grounded to the rest of the system. easy peasy. just mount it on a block somewhere down in the bilge out of the way.
Thanks,
I had an inkling that it would be described as you did !!
 

Capt. Rick

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Perhaps you might have room for a "collar" zinc on the shaft right behind the prop. BTY, if you guys are not familiar with www.boatzincs.com
check it out, great pricing and you can check out the zinc I am referring
to.
 

rusty12

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Zinc

Collar will cause too much cavitation according to several gm owners.

Thanks for info guys
 
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