Zinc slid down shaft
- Thread starter ALKA2710
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I assume he is out of water for good with winter so no dive needed.
I doubt it damaged anything, if it had enough room to slide down it probably had enough room for water to flow and keep cutlass from getting hot.
Plus its all under water.
I would want to know why it slid, was it not tight? Perhaps consider using some locktite on screws.
I don't have shafts but when I did I would tighten those things super tight.
Maybe shaft is getting hot and that expanded something. Check your dripless and make sure it is dripping!
I doubt it damaged anything, if it had enough room to slide down it probably had enough room for water to flow and keep cutlass from getting hot.
Plus its all under water.
I would want to know why it slid, was it not tight? Perhaps consider using some locktite on screws.
I don't have shafts but when I did I would tighten those things super tight.
Maybe shaft is getting hot and that expanded something. Check your dripless and make sure it is dripping!
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The classic problem with this is no one took a hammer to the zinc after the initial tightening. Once tight, I beat the zincs with a hammer a few times and tighten them again. A few passes and they stop needing another treatment. On shaft zincs I hit both sides of the shaft zinc a few times then tighten. Same on all other zincs like pancakes on both sides of the rudders and trim tabs.
I am out for the winter and did take a quick look at the zincs and the piece on the zinc that has the screw hole was eaten away. Didn't see any damage but didn't have time to remove the zinc. I install my zincs myself and always take a rubber mallet to them and re tighten. Will give a good inspection to the bearing and housing and just keep an eye on it next year. Thanks
Al
Al
I would not put locktite on the threads. If the shaft zinc corroded away, you need to replace them more often. If you only have one, you should have two. If you already have two, you need to test for excessive electrolysis at your marina next year. If it appears that the casting was bad or you hit something, then I would treat it as a one-time occurrence and not worry about it. As stated above, always hit them with a hammer all around the zinc and tighten them again. Use a 90 degree allen wrench and not a screwdriver type allen wrench so you get more power behind your tightening. I also double-nut my rudder zinc so it doesn't come loose.
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Even at work where we run our boats really hard, I've never used more than a dead-blow hammer on the zincs before re-tightening. Only time I'd use a 'real' hammer on the running gear is on a prop puller. (And then, I do it from the side - when a wheel is really, really stuck on there, they come loose ALL at once when they finally break free. I've seen plenty of boatyard injuries from that.)
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I think a dead blow is more assertive than a regular rubber mallet. Rubber mallets have no weight correct? I just bang away a few times on each side. It's not like I whack the heck out of it. This mars the surface a little and nothing else. It's not like I am pushing the shaft out of alignment.
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If you have access, install shaft brushes in your engine room, the 'brush' is mounted to the stringer and rests on the top of the exposed shaft after the coupler in your engine room.
You also bond the 'brush' to your boats bonding system and your hull plate zinc now takes over the job of protecting the shaft. Boatzincs.com sells a double Divers Bream plate if you are concerned about the hull zinc not being large enough to last the season.
The brush eliminates the need for additional shaft zincs and the associated problem like you've had with this one. Plus shaft zincs aren't cheap!
http://www.fisheriessupply.com/pro-mariner-shaft-brush
You also bond the 'brush' to your boats bonding system and your hull plate zinc now takes over the job of protecting the shaft. Boatzincs.com sells a double Divers Bream plate if you are concerned about the hull zinc not being large enough to last the season.
The brush eliminates the need for additional shaft zincs and the associated problem like you've had with this one. Plus shaft zincs aren't cheap!
http://www.fisheriessupply.com/pro-mariner-shaft-brush
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Yup. Probably wouldn't hurt it with a regular hammer as long as you're not going all rabid monkey on it, but I'm just not comfortable doing it. Which, admittedly, is out of character for me - I learned to run boats with overbuilt and under complicated steel hulled Motor Lifeboats where brute force was the answer to every operational or maintenance issue. Boats and just about everything else are built more delicately nowadays...
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I've never understood the need for those brushes. The engine should be connected to the bonding system as well as (potentially) the gearbox. There has to be enough metal in contact to allow the required current to flow or not.
Regardless I don't see a rubber mallet generating enough impact to reset the zinc.
Regardless I don't see a rubber mallet generating enough impact to reset the zinc.
I agree. And on my boat, I also have the shaft, rudder, and water intake thru-hulls included in the bonding. What I don't have included are the trim tabs - because they are stainless and have their own dedicated zincs.
My winter yard installs the 6 U/W zinc anodes before spring splash but I try to get over there to America before it goes in to beat on the 2 shaft anodes and further tighten and check the others .
Then, at least 2-3 times a season or more I go under with a mask , Allen wrenches & dead blow mallet to check/tighten again or replace any which appear ~~ 1/2 gone. There are always a few which are a bit loose and usually 1 or more in need of replacing.
I replace the cheap 2-bolt shaft eggs the yard installs , with heavier HD 4-bolt type which I find to be much less prone to sliding aft to grind against the strut . Spares for all sitting on the swim platform are kept ready to install if needed.
I shake the prop to check for any cutlass wear and turn the prop to feel for any grinding in the cutlass, and check the running gear for any rope or fishing line fouling, then scrub slime from the bottom and waterline with a soft long handled brush.
Alka- I suggest you turn the props to feel/listen for abrasive friction in the cutlass which will score the shaft if anode debris is wedged in there.
BTW, Hope you all are dutifully remembering to check any/all HE or cooler pencil anodes. Manuals commonly say to do this every 30 days. I replaced at least 3 on my heat exchangers this season ( no anodes in my oil coolers.)
Then, at least 2-3 times a season or more I go under with a mask , Allen wrenches & dead blow mallet to check/tighten again or replace any which appear ~~ 1/2 gone. There are always a few which are a bit loose and usually 1 or more in need of replacing.
I replace the cheap 2-bolt shaft eggs the yard installs , with heavier HD 4-bolt type which I find to be much less prone to sliding aft to grind against the strut . Spares for all sitting on the swim platform are kept ready to install if needed.
I shake the prop to check for any cutlass wear and turn the prop to feel for any grinding in the cutlass, and check the running gear for any rope or fishing line fouling, then scrub slime from the bottom and waterline with a soft long handled brush.
Alka- I suggest you turn the props to feel/listen for abrasive friction in the cutlass which will score the shaft if anode debris is wedged in there.
BTW, Hope you all are dutifully remembering to check any/all HE or cooler pencil anodes. Manuals commonly say to do this every 30 days. I replaced at least 3 on my heat exchangers this season ( no anodes in my oil coolers.)
Looks like my rubber mallet is out next year will use a dead blow. Zincs are in really good shape, less than a quarter were eaten away for the season. As for pencil zincs I have Merc 8.1 L fresh water cooled and can not find any zincs any where am I missing them. I did find a pencil zinc on my Kohler generator which I change out.
Al
Al
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Yeah, my zincs were not that eaten this year at all but my paint on the transom took a beating.
I think Walter noticed a similiar thing on his boat.
I know we are all on the same canal in AYC.
Not sure what it means. Seems something reacted with the copper in the paint more than the zinc.
I may switch manufacturer of my zincs next year.
As for the pencil zincs, look on the heat exchanger, if never changed before, they may be painted and hard to recognize.
I think Walter noticed a similiar thing on his boat.
I know we are all on the same canal in AYC.
Not sure what it means. Seems something reacted with the copper in the paint more than the zinc.
I may switch manufacturer of my zincs next year.
As for the pencil zincs, look on the heat exchanger, if never changed before, they may be painted and hard to recognize.
Transmissions don't have a reliable electrical path to the shaft. Oil on gears etc isolates them. Rubber damper plates do the same and the case is isolated from the shaft by the oil seal. Te output flange connection may or may not be good electrically.
Every marine gas engine heat exchanger I have seen has had a pencil zinc. That said , a quick look at parts diagrams for Mercruiser 8.1L engines does not seem to show pencil zinc on the diagrams incuding the HEx and oil cooler which also sometimes has one..
But best make sure of that with Merc or a dealer tech as those parts are expensive to replace & that's something you don't want to have to do if it could be avoided with anodic protection.
Will look again tomorrow for the heat exchanger zincs. The zincs held up real well this year also when I was hauled had very little slime and found only 1 barnacle. Paint also seemed like it held up even on the transom. Was looking at Walters boat yesterday being it is almost right behind mine and will take a look at the transom paint to see what I missed.
Al
Al
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Hey keep buying shaft zincs, I don't have to and don't miss getting under there with the hammer and allen head wrench.
The shafts need protecting and this is the best way. Take a look at all of your high end boats like Fleming and you will find shaft brushes on all of them.