Diver said prop has pink hue

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cardude01

cardude01

Guru
Joined
Nov 26, 2012
Messages
5,290
Location
USA
Vessel Name
Bijou
Vessel Make
2008 Island Packet PY/SP
I had the boat cleaned recently by a diver at this new marina in New Orleans. He said everything looked fine except for my shaft zinc being pretty wasted, and he also said the prop has a bit of a pink hue.

What’s the deal with the pink? Do I have some electrolysis going on?
How does one check for this and how soon does it need to be done? I’m back in Texas.

Also, do I keep using regular zincs in Lake Ponchatrain or do I need to switch to aluminum?
 
If it's in a fresh water lake, definitely switch to aluminum. Zinc anodes generally don't work in fresh water unless you scrub the coating off them frequently (as in every few days).
 
It’s not totally fresh, but brackish. Apparently it’s 3.5 ppt vs the Gulf at around 20-30ppt.

My galvanic isolator ground fault light lit up when I plugged into this marina a few weeks ago, but don’t know if that’s related. IMG_4630.jpg
 
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cardude01 said:
It’s not totally fresh, but brackish. Apparently it’s 3.5 ppt vs the Gulf at around 20-30ppt.
Click to expand...

I'd definitely go aluminum in that case. Saves the risk of zinc anodes maybe not working, but the water isn't so pure that you might need magnesium (aluminum will definitely be active enough).
 
Pink hue isn't a great thing but on a slow turning prop, I have seen them last a long time, as long as the problem gets resolved ASAP.

Not sure if stray current can do the same as galvanic.

If the prop hit with a hammer still has a good ring and isn't dull, a good but not perfect answer.

I also have seen prop nuts that didn't look too bad but they would crumble in your hands.

Probably best to haul and get it all check out as well as your zincs (preferred aluminum in your case)/bonding system.
 
If the boats going to be there for awhile, I’d get a corrosion analysis done while you’re in the water. Changing the zincs doesn't fix the problem if there is one. Just saying.
 
Larry M said:
If the boats going to be there for awhile, I’d get a corrosion analysis done while you’re in the water. Changing the zincs doesn't fix the problem if there is one. Just saying.
Click to expand...


Yeah I need to find someone to do that. Who does that kind of thing?
 
cardude01 said:
Yeah I need to find someone to do that. Who does that kind of thing?
Click to expand...

When I was first getting started working for a marine electronics firm in NJ, some guy from NC called, his boat was at Jarrett Boat Works and had an issue that the yard completely screwed up and somehow was referred to me.

If someone though I was an expert that was worth calling over all the other possibilities between NC and NJ...man the industry must have been hurting back then.

My point is that a lot of people claim expertise, but as we all have seen only a handful can actually be trusted or worth what we pay them.

So be careful, from what I still read on the net, there are few that really are experts and I KNOW I am not one of them....but I can spot a BSer.

A lot of people on TF recommend all kinds of service people, from surveyors to mechanics, based on their experiences....but from reading their posts....I just can't accept they have enough experience to know who in the industry is really all that good or bad.

Bottom line.....good luck finding a great tech in this arena...you will need it. :eek:
 
Yeah I generally hate hiring people to work on the boat. I’ve had so many bad experiences.

I do have a silver cell, but don’t know how to use it. Maybe I can read up and figure it out.
 
cardude01 said:
Yeah I generally hate hiring people to work on the boat. I’ve had so many bad experiences.

I do have a silver cell, but don’t know how to use it. Maybe I can read up and figure it out.
Click to expand...

It's not that bad...I used to do mine and somehow the word got out when a few people I helped thought it was a big deal.

I dad some independent instructions for using the cell....but I can't remember if they went with the boat when I sold it.
 
I had that problem. They did Nondestructive testing.... they recommended, buy a new prop. Took it to the yard for a new prop, had them check and clean the bonding system, problem went away.
While you are out of the water, check the shaft zincs. Remove the shaft zincs, brighten the area on the shaft and the inside of the zincs then, reattach the zincs
 
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Definitely check Steve Ds articles. You need a marine electrician that is ABYC certified in corrosion control, not an easy thing to find. I bought a silver half cell from Boatzincs.com. It came with pretty simple instructions. I would only use aluminum anodes wherever you boat, because they are good everywhere. That way there is no question if you have the proper anode, with aluminum you do have the proper anode wherever you boat. And aluminum anodes are better for the environment than zinc anodes.
 
Hey Dude:

I'd be concerned about that ground fault light.

This article explains what a galvanic isolator does in very clear terms.

https://www.boatus.com/expert-advice/expert-advice-archive/2019/october/galvanic-isolators-explained

The article also notes that if your galvanic isolator is old, you need to have it tested:

"If your boat is plugged into a dock regularly, you need a galvanic isolator (or an isolation transformer). If you have an older boat with an isolator installed, you should have a marine electrician test it to ensure that it is functioning properly and that it meets current standards that apply.

Early isolators had inherent shortcomings that can make them unsafe. The problem is that you won’t have any idea whether it is functioning without testing the unit properly. If in doubt, get a qualified marine technician to test it or consider replacing with a new fail-safe unit."

Cheers,
Mrs. Trombley
 
If your isolator is old, don’t even bother testing it just put a new one on. The older ones have to have the wiring disconnected to test, real PITA. The newer ones that meet ABYC have to have an indicator to show that they are working or not.
 
That one will do 2 30 amp inlets. It is very simple to install. If access is good probably less than 20 minutes.
 
Thanks. I have two 30 amp inlets. Will get it ordered.
 
Keysdisease said:
I had the pink prop too, not a good color for a Mans trawler



dezincification which is what you're suffering from. :thumb:
Click to expand...


What did you find that caused it? I have a new zinc on the shaft, but I think it’s zinc and not aluminum.
 
We had our boat hauled for new bottom paint and the yard manager told us both props were bad because of 'pink eye." One of the yard workers told us ignore it, they're churning for work. I did ignore the "problem" and that was 18 years ago.
 
psneeld said:
If the prop hit with a hammer still has a good ring and isn't dull, a good but not perfect answer.

I also have seen prop nuts that didn't look too bad but they would crumble in your hands..
Click to expand...

Ive seen bad de-zincification in the yard. Owner would ask “why is my prop pink?!?” I would just give a Good hit to one blade with the palm of my hand and the blade would brake off.

Additionally, i had a boat for a decade. Used half a zinc a year. Brought it to a buddies house to use his lift to do work.

Changed the zincs while she was up. Had it in the water 3 weeks there. The new zincs were eaten up in 3 weeks. Was stray current from dock wiring.

If you were somewhere new, stray current is a bitch

Amazing the owner would thank me for breaking his prop, lmao.

Maybe not so in your case, but definitley check.
 
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psneeld said:
When I was first getting started working for a marine electronics firm in NJ, some guy from NC called, his boat was at Jarrett Boat Works and had an issue that the yard completely screwed up and somehow was referred to me.

If someone though I was an expert that was worth calling over all the other possibilities between NC and NJ...man the industry must have been hurting back then.

My point is that a lot of people claim expertise, but as we all have seen only a handful can actually be trusted or worth what we pay them.

So be careful, from what I still read on the net, there are few that really are experts and I KNOW I am not one of them....but I can spot a BSer.

A lot of people on TF recommend all kinds of service people, from surveyors to mechanics, based on their experiences....but from reading their posts....I just can't accept they have enough experience to know who in the industry is really all that good or bad.

Bottom line.....good luck finding a great tech in this arena...you will need it. :eek:
Click to expand...

Thanks, great post!
We are surrounded by incompetence!
 
Long story short-
I saw another fisherman's blades go on a 36" prop in 3 weeks from a 12v instrument wired backwards. The remaining hub was pink.
 
So to find the isolator I would look on my incoming AC and it'll be in there between that and my panel correct
 
Dude! That’s a girls prop!
 
It’s not just your zincs and bonding system. AC, neutrals and grounds plus the other boats on the dock all come into play. It’s an easy process to check it out. The problem is finding a competent technician.
 
Larry M said:
It’s not just your zincs and bonding system. AC, neutrals and grounds plus the other boats on the dock all come into play. It’s an easy process to check it out. The problem is finding a competent technician.
Click to expand...


The only thing I run off AC power on the boat when away are three fans and that big dehumidifier. Sure would be nice to just unplug the boat and rely on 12 vans and my battery bank and solar panels. But I’d miss the dehumidifier.
 
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