Is this normal wear and tear or electrolysis? 2 + years old, regular use.
EDIT:
After enlarging your pic, and seeing the powder coat blistering, like it is.
It looks like you might have a stray current problem, causing severe electrolysis?
Down below my thoughts is a C&P from the web, but it explains some possible problems you might look into. Good info.
I’d make sure the TM isn’t grounded to anything other than the TM batteries first, that’s my guess.
In the end when you finally figure out the problem it can only be one of the following three things causing the corrosion.
1st is stray current
2nd is dissimilar metals in contact with each other
and the 3rd is improper grounding.
I hate chasing electric gremlins in boats. Best of luck
C&P…
The underlying issue is that your TM case is at a different voltage than something else in the water nearby. Likely the hull or outboard lower unit, though those should be at the same voltage. Normally what happens is that there is a connection between one of the middle wires on the TM system to outboard ground which gives you 12 or 24V difference between the TM housing and outboard LU and current flows through the water.
First thing would be to verify that your TM is actually seeing 24V at the front of the boat. Measure at the TM wires themselves.
You can try measuring between the prop nut and outboard battery negative with a voltmeter. Turn on master power and your TM breaker. Try combinations of equipment like electronics on and off.
What is connected to your cranking battery? Second battery for electronics? Outboard powered charger?
What things like transducers, hydrowave etc. are in the water while you are fishing?
Anything non-standard on your boat?
Good info, thanks! Dealer said he thought paint got knicked and saltwater is eroding it. I have 0 electronic skills. I do typically leave engine in the water while trolling. Sacrificial anodes are getting some wear and tear if that means anything.
Nicked paint on the skeg does not relate to the blistering I see on the motor housing. Just my .02 cents.
That’s dew on the housing.
If that’s dew, your problem appears to be just normal wear and tear…
Copy. Sorry the photo was confusing- skeg peeling is the question.