jfreedman

Looking for help from people more knowledgeable than me. Is this damage to the lower unit electrolysis damage or something else? If it's electrolysis, could there be more internal motor damage that I'm not seeing? Also, this boat was supposedly dry stack stored so how does this happen on a 2016 boat?




There is minor damage to the skegs that has been repainted. Would this scare anyone off?

Jumpsummo

That can be repaired. Your zincs okay? You do need to repaint any bare metal it safe.

Jumpsummo

That can be repaired via welding. Your zincs okay? You do need to repaint any bare metal to keep it from eroding due to just high speed running.

UncleLuke

Yup, looks like a 3 year old Mercury!

mystery

given the chip, it appears that these were run aground?

could be contact damage, paint issue, or electrolysis, hard to tell

evanP220

looks like they were run aground. the zincs look nearly new from what I can see in the pictures

ziess21

Most definitely damage from electrolysis, the pocking on the skeg confirms it.

SWF Pontoon Angler

Huh?? None of mine ever did that.

SWF Pontoon Angler

But then why only on the skeg?

SaltBoater

I don't get it. There is a very fresh looking zinc visible in the top pic. That's not electrolysis.

Something is wrong with the paint or the application or the care. It shouldn't do that. Especially if this is rinsed and dry-stored.

What's going on?

I can only guess at things. I notice there is a cover on the sides of the lower leg. My old motor doesn't have that. Is salt water staying up in there and seeping down over time? It looks like it was never rinsed.

My 23 yo Merc doesn't look like that. All the paint is GONE off the skeg, never repainted, bare metal. It was like that when I got it. It's not advancing much at all. There isn't much corrosion around it. Maybe just a bit at the edge of the paint / bare metal border. From there on up, and certainly above the cav plate, all the paint is rock solid. Faded, but still doing it's job. None of that bubbling up blisters with corrosion under it.

Makes me wonder if that one is a factory mistake. Maybe they let the bare metal get exposed to the sea air before the paint got on it. Maybe it was built on a humid day. I can only guess. It should not do that. Certainly not in 3 years. That's crazy.

Is that your boat or one you are just looking at?

If it's yours and it's under warranty it's time to take it back. It should not do that with proper care.

If it's one you're looking at I can understand why it is for sale. That is advancing too quickly to get any kind of good feeling it's a keeper. And if that's what it looks like outside those white side covers, I wonder what it looks like inside. If it looks like that when it's three years old then what's it gonna look like after 6 years or 10?

Cobia 217

How high do you trim the motors when running? Cavitation or ventilation-related?

c1steve

He is looking at a used boat. My best guess is electrolysis from being in a hot harbor or a wiring problem. The new zinc would have been replaced after the damage was found.

jfreedman

The zincs are new and were replaced when the dealer took the boat in trade. This is a boat I'm looking at buying. Is this something that can be fixed under warranty if it was not cared for properly? The dealer said it was dry stack stored but I'm not familiar with how those facilities work. Who flushes the motors? Who sprays the boat down before it's put on the shelf? The dealer says the boat was kept in a shallow marina and the skegs dragged in the sand. Maybe the skegs had the paint scraped off and there was also electrical damage? I don't know. Just trying to decide if this is a deal breaker or just cosmetic and can be repaired.

rpontual

This seems to be electrical damage. I scraped off the tips of mine and never painted, nothing like this happened.

I had an engine that the anodes were not correctly installed and electrolysis damaged like this, making holes. Perhaps the previous owner raised the engines enough for the zincs to be out of water but not the tips.

This is unlikely a warranty claim.

jfreedman

Yes, you're correct. Must be a wiring issue if the boat was dry stack stored though right? Not sure if it could be a hot harbor if the boat gets pulled for storage. The boat is in Jacksonville FL. I understand the corrosion on the skegs but the paint bubbling on the top of the LU is curious. Maybe from not rinsing the motors or anything. Someone repainted the skegs so I'm trying to find out if that was the dealer or someone else.

TsunamiTsling

Looks Like Electrolysis to me - 12v grounding or bonding issue with the motor brackets. Surveyor will mention that. A good marine electrician can track that down for you.

rpontual

When I experienced an electrolysis issue due to incorrect anode installation, the corrosion manifested as paint bubbling such as that one on the picture.

mystery

electrolysis can happen only or be predominant only only one in a twin setup

mystery

a fresh looking zinc doesnt mean much

couldvbe been changed after the fact

could be the wrong type of anode (zinc v. aluminum etc)

or could not be properly bonded and not sacrificing itself

jhackl

Looks like it sat for a period of time with the motors trimmed so that only the tip of the skeg was in the water and the anodes were not.