Zinc Question

J

Jims380DA

Member
Mar 5, 2007
286
CT
Boat Info
2000 Sea Ray 380DA, Kohler Gen
Engines
8.1L 496 MerCruiser
Just curious if any of you guys use shaft zincs. Some of the guys at the marina think im nuts for not using them. I was told by my dealer's service mgr. and by Sea Ray customer service not to use them. Any thoughts? thanks
 
You should use them,you don't want those shafts to be eaten up and you don't want to know the replacement cost compaired to the cost of zincs!!!
 
Jims380DA said:
Just curious if any of you guys use shaft zincs. Some of the guys at the marina think im nuts for not using them. I was told by my dealer's service mgr. and by Sea Ray customer service not to use them. Any thoughts? thanks
Click to expand...
I'm with you. I was told by Sea Ray people that Sea Rays don't need them for some odd reason.
I'm anxious to see how this post shakes out.
Jack
 
I've never used them... probably because Sea Ray told me not to.

I would say in our yard here at Bluewater I see about half the boats with them and half without.
 
From Sea Ray's website... No mention of Shaft Zincs. I was told the shafts are somehow protected by the zincs on the transom. I also read a post on here, about a shaft zinc that worked its way down the shaft and wedged into the unit (I forget what its called) that holds the shaft and nearly ruined the bearing. I don't use then and I don't see them on other searays in my yard.

Electrolysis corrosion of underwater metals on power boats can result in serious deterioration. The boat owner must be aware of the possibilities of galvanic action (the deterioration of underwater metals due to dissimilar characteristics when placed in salt water) and/or electrolysis. It is the owner's responsibility to check for and replace parts damaged by galvanic deterioration. Refer to your Sea Ray® dealer to investigate the source of stray corrosive currents. Inboard/outboard and outboard engines are fitted with zinc anodes on their lower units (refer to the engine operator's manual for their locations). If your boat is equipped with trim planes (tabs), zinc plates are installed on the trim planes (tabs). Zinc protects underwater hardware. Zinc, being much less "noble" than copper-based alloys and aluminum used in Sea Ray® underwater fittings, will deteriorate first and protect the more noble parts. Zinc anodes generally require replacement about once a year; however, they should be checked weekly. In salt water areas, replace every six months. The need to replace anodes more frequently may indicate a stray current problem within the boat or at the slip or mooring. If zinc anodes do not need replacing after one year, they may not be providing proper protection. Loose anodes or low grade zinc may be the problem.
NOTICE: Do not paint between the zinc and the metal it contacts, and do not paint over the zinc.
 
Jims380DA said:
Just curious if any of you guys use shaft zincs. Some of the guys at the marina think im nuts for not using them. I was told by my dealer's service mgr. and by Sea Ray customer service not to use them. Any thoughts? thanks
Click to expand...

For last few years sea ray is not recommending using shaft zincs. They are getting loose on shaft and may cause damage to underwater gear. Your shaft will be OK if bonding system on your boat is in good shape - no loose or broken bonding wires, rusty connections, etc. You can use zincs if you want, but sea ray will not honor warranty if there is any damage to bottom or shaft caused by broken shaft zincs.
 
While on the subject of zincs I noticed that my TNT swim platform was not bonded. The brakets were eating zincs. I bonded the brackets to the rest of the system and the consumption of zincs went down. Those of you with swim TNT swim platforms should check them. Sea Ray is not known for bonding this option.

The prop shafts and the props should be bonded through the engine. As long as the bonding is good there should not be an issue them. Stainless steel is more than zinc and therefore the zinc on the stern should go first.

Mr Salt
2001 540 CPMY
Caterpiller C-12s
Cape May, NJ
 
I am another that does not use them. Probably will continue not using them unless I start seeing signs that I should. Nothing so far shows I do need them. I think in my case where the boat stays on the lift 50 percent I really do not have the need for them.
 
I just bought some, for one I would like the see how they react. I have talked to a number of people who use them, I just want to be sure that my bonding system is working properly after I ohm check it all to the grounding system.
 
SR's bonding system is designed to make shaft zincs obselete. HOWEVER, I still use them and they are mildly eaten at the end of the season. I use two on each shaft a collar type and a typical shaft zinc.

Collar type up closer to the hull

collar.jpg


Shaft type closer to the strut

X-5.jpg


I think the fear of them slipping down and banging around the strut is what makes people leary of installing them. BUT before the concept of the bonding system, these were the only game in town and they did the job.
 
A friend who uses them told me that once you tighten them, give a few taps on them to be sure they are tight against the shaft and then tighten them the rest of the way. I guess I'll see what they do. Nice pics Ron, stolen from boatzincs I see! You are so bored, I think you need a vacation to help buff, bottom paint, tune up, clean, lube, etc.. Let me know when and I'll send you the address.
 
Mark
That's exactly what you have to do. When you install these things, just as important as the allen wrench is a hammer! You'd be surprised how much tighter they will get after you THINK that's as tight as they'll get. You MUST batten them down equally on both bolts as far as they'll go. Then you gently tap each side equally a few times and when you put the wrench back on, you'll get another 1/4 to 1/2 turn. Repeat this process until there's no more tightening to be had, which could be an additional 3 or 4 cycles.

I've got plenty to keep me busy up here, thank you very much :grin:. It's just too damn cold to work on the interior stuff I need to do before pulling the cover.
 
I specifically asked Searay, as my 2007 320 does not have them. They said not to install them on the shafts on my boat.
 
WOW Dom that's an old thread. That's when I used to type with no caps!

So do you continue to use shaft anodes or not?
 
I replaced my shaft zincs yesterday and they had more wastage than the hull zinc did. I use two per shaft and have done the same on all three of my Sea Rays. I will tell you that none of them were delivered from the dealer with shaft zincs and the dealer here only serves the salt water market so they know the application. Nonetheless, I am more comfortable with more protection rather than less in this instance. From a corrosion protection perspective it is probably fairly safe to say that Sea Ray is correct in not applying zincs from the factory, at the same time if a shaft zinc broke free and damaged the hull or strut Sea Ray would be exposed to a warranty claim while if shafts corrode as a result of the owner not maintaining appropriate corrosion protection.....well that would be a maintenance cost for the owner. Seems like good risk management on the part of Sea Ray so I do a little risk management of my own and use shaft zincs, that I take great care to tighten while using loctite on the four screws....maybe a little overkill but it makes me sleep better.
 
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My boat didn't come with them. The first time our local dealer did a complete bottom job, they didn't add them. The second time they did a running gear job, they put them on. Soon, one came loose and wore against the shaft support. I re-set it. The other one came loose. I took them off. Yes, they had wear, but that doesn't mean that the transom one doesn't work. If the transom one did have good continuity with the shaft through the transmission, it will work, and both it and the shaft ones will wear.

I think you are better off with them than without from a perspective of absolute maximum protection. I don't think they are absolutely required, or even worth the hassle.
 
After that event in May of 2007, I did re-nstall shaft zincs, BUT, I installed them....the right way...with two opposing ballpean hammers and an allen wrench.

MM then re-hauled my boat in October 2007 to repaint the bottom and I agreed to NOT install shaft zincs.

I will be doing a short haul in April to paint, wax and swap out props. I haven't decided yet which way to go....
 
I could get probably 3 seasons from my transom zinc & two from my trim tab zincs. One is all that can be had from the shaft zincs. My boat is older and probably has some really weak bonding system connections, but as Brian stated above, I'd rather err on the side of caution. Proper installation is KEY. I seriously doubt that any yard uses a master mechanic to install anodes. It's just not cost effective. I'd imagine that is relegated to first years with a crash course in bottom painting and bolt tightening.
 
I use them on my 44SB as I did on my other 4 boats. We stay in the brackish Clear Lake of Houston and do not subscribe to a dive service any longer. I haul the boat every 9 to 10 months for new external zincs and a pressure washing. The anodes are always at least 60% gone, even on the shafts, so they must be doing something. Best of luck,

Jet Lag
 
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