Strut Replacement

Ron20324 · Mar 12, 2011

Duh... call Hunter?

RAD · Mar 12, 2011

You got something bad going on with electrolisis........is there a bond wire on that strut from the inside?

Allan12210 · Mar 12, 2011

Drill a hole through it and use a pancake zinc on either side. That will prevent any further change. You will find as you drill it is fine inside. Mine looked just like yours 20 years ago and it is still sound.

Allan

Ralph Johnstone · Mar 12, 2011

Yes, there is a problem with corrosion .................

.................. however, if you scrape the surface of the strut with a blade, I'm betting the dezincified surface is no more than a thou or two in thickness. You should look at attaching a zinc or bonding wire to the strut (on the inside) just to be safe.

Right now, I'd say you biggest worry is the mechanic. Don't forget, most of these guys couldn't make it as squeegie kids and that's why they moved over to boat mechanics. 98% of them are completely useless.

s sauer · Mar 12, 2011

Electrolysis

I've had the exact same situation occur when I was having the Cutlas bearing replaced and the strut was soft and 'pinkish'; however. I trust the integrety of the Yard and appreciated the warning. In my case, I then thought back to a situation the previous season where a nearby boater had let his power cord drop into the slip and it was several days before it was pulled out (by me). Later I checked other bronze on my boat and found a de-zinkified thru hull and noticed a nearby C&C with a 'spangle' pattern across the bottom paint on his keel, so there had definitely been some electrical interaction or electrolysis in the nearest slips.

Steve Dion · Mar 12, 2011

Yes, I would agree to call Hunter. You have a newer model, they may have them in stock or can direct you to their mfg.

Allan12210 · Mar 12, 2011

Ralph hit the nail right on the head. You know there are sharks out there and not all of them are in the water. Some are going to try and take a big bite out of your wallet. Your picture looks like only surface effects so either scrape it and look for the bronze color to return or after drilling a hole (which you should do anyway) look in the bore and you can see a cross section of your stut. That will tell you how deep the dezincification extends. Because of the lack of serious erosion on the suface, I am betting it is only minor. Make sure inside the boat that there is no wire attached to the mounting screws then use a dedicated zinc for the strut and it should be fine from here forward.

Maine Sail · Mar 13, 2011

#1 Call Hunter. This should not happen if properly installed & protected. If that is a quality marine strut bronze, as in Nibral, that amount of dezincification almost never happens as there is not enough zinc in it to cause that pinkish coppery color when dezincified. Hunter generally uses Manganese Bronze/421 which is less expensive but really MUST be zinc & corrosion protected. Many builders use Manganese Bronze because it is cheap and strong but the drawback is that it is easily eaten away by corrosion if not protected.

#2 I would clean the entire strut with a burgundy Scotch Brite wheel or soft brass brush on a drill. If it is dezincification I will disagree with the others here that this is a "non-issue". There have been many struts and props and seacocks that have failed from dezincifitation. It can be dangerous and if it fails it will cost you a LOT more to deal with than addressing the problem up front..

I have seen quality marine rated bronze at 40+ years old with zero dezincification while a manganese "bronze" prop next to the strut or rudder shoe is totally eaten away. That is the difference between a high zinc content bronze and a low zinc content bronze. Low zonc content bronze can last but only if protected.

Personally I would not put my name on that strut and send you back in the water either. There is a liability in doing so.

More:

It's not just skin deep:

My own friend at the prop shop flat out refused to even touch this prop, to much liability:

woodster · Mar 14, 2011

Rasselas36 said:
I was having my cutlass bearing replaced when the mechanic noticed my strut was discolored. They recommended I replace it. The boat is only 6 years old? I have had a diver cleaning and keeping the zincs up to date every month. The marina said that bronze has gone soft when it turns pink. They are getting me a price for a strut but I have no idea what a reasonable price is and cannot find a price on Google. Can anyone help me ? I have attached a pic of the strut. Thanks.

there is a place in Alganac Michigan that makes thoses ...i am haveing the same problem on my boat ......when i contacted them they said they were the company that made them for the S-2's back then and also had the pattern in stock on the shelf ...i was talking with a lady when all this was done ....(before any one gets up tight about me being shovanistic PLZ dont because i am far from that)..but she would not give me a price and told me i would have to contact a dealer to buy it from them....and she is prolly just doing her job the best she knows how.....i am what they call a good old boy and not good at playing that game...i like to talk the the man in the shop that is in charge of making them but for now that hasnt happend.....so i will bid my time untill i find the back door for the part to be made.... i wish i had more to share with you but for now that is it.....oh and btw mine is still in tact but its looks a lot like yours ...i have shown it to several people in person and they have all said to use it.....not so sure about that...all i know is that when i hit it with a hammer it has no ring to it at all sounds like rover looks when you comand him to do something and he just lays there as if you never said anything .......

regards

woody

RAD · Mar 14, 2011

reprinted from a cruising world article
According to the American Boat And Yacht Council, all underwater hardware should be bonded. This includes shaft, struts and stuffing boxes. Bonding performs several functions -- most importantly, electrical shock prevention for shore-power equipped vessels. Next comes lightning protection/dissipation and third is corrosion protection. Simply stated, if all underwater hardware is bonded and electrically attached to a zinc it is better protected from galvanic corrosion. A shaft brush can be a worthwhile addition to any bonding system. This device provides a better connection between the shaft and the bonding system than the transmission would offer. The stuffing box, stern tube and strut should all be attached to the bonding system with at least #8 AWG wire or copper bonding strap. Obviously the shaft should be provided with at least one zinc and so should the strut, if provisions are made for it. Be sure that any underwater gear is free of all anti-fouling paint before installing a zinc.

Strut Replacement

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