Unusual amount of corrosion after first season

[losacco]

Here's my situation, new owner of a 2016 Yamaha sx240. We wet slip at a new lake house near Columbus, Ohio. Pulled the boat out at season end and noticed what I thought to be a lot of corrosion, pitting on pump aluminum and a lot of anode fuzz.

The slip at the house has an electrical outlet that I use to plug in a battery charger for battery maintenance and bilge pump, could sometimes be a week or more between trips to the lake.

I'm reading a lot about shore power ground issues causing corrosion and remembered the house inspector saying the slip power was not grounded, didn't think much of it at the time until now.

Any help would be appreciated
Patrick

 

[FSH 210 Sport]

Here's my situation, new owner of a 2016 Yamaha sx240. We wet slip at a new lake house near Columbus, Ohio. Pulled the boat out at season end and noticed what I thought to be a lot of corrosion, pitting on pump aluminum and a lot of anode fuzz.

The slip at the house has an electrical outlet that I use to plug in a battery charger for battery maintenance and bilge pump, could sometimes be a week or more between trips to the lake.

I'm reading a lot about shore power ground issues causing corrosion and remembered the house inspector saying the slip power was not grounded, didn't think much of it at the time until now.

Any help would be appreciated
Patrick

The slip power not having a ground is not a good thing safety wise, and could very well be contributing to the corrosion you saw. At the very least get an electrician to correct the ground situation and install GFCI (ground fault circuit interrupter) plugs at the dock. As a fyi, sometimes GFCI will trip when you first plug in a battery charger, just reset it and plug it in again.

 

[losacco]

The slip power not having a ground is not a good thing safety wise, and could very well be contributing to the corrosion you saw. At the very least get an electrician to correct the ground situation and install GFCI (ground fault circuit interrupter) plugs at the dock. As a fyi, sometimes GFCI will trip when you first plug in a battery charger, just reset it and plug it in again.

Thank you
When I resolve the ground issue, is there a way to check things when I put the boat back in next season and not waiting till the end of next season for corrosion?

 

[FSH 210 Sport]

Well…. I suppose if you were to take a high quality multi meter you might be able to start taking milliamp / mili volt readings all over the dock and your boat.

Definitions: The neutral wire, larger of the two prongs that go into a plug, is to return the unbalanced flow back to the transformer. Grounds on the other hand are to remove potential difference between a device and ground, grounds are essential in protecting you from getting shocked say between your washing machine and the faucet on the sink. Grounds also eliminate static sparks.

I mentioned GFCI plugs before, these devices are VERY sensitive about flows on the ground wire and will interrupt the circuit to protect you from getting electrocuted, but they need to have a good ground to function properly. An electrician should be able to take some Meg Ohn readings before and after to show the result of proper grounding. The inspector said there was not a ground at the dock, the inspector, I’m guessing, probably used one of those little plug in thingies that looks like a connection but has lights on it to show what is going on. Again a guess, it could be that there is a ground wire on your dock but the connections got corroded or something, hopefully that is what it is and the repair cost will be minimal.

Here’s my best guess as to what is happening. There are transients trying to find their way to ground, in other words there is potential difference between your boat and ground. Since the bonding (grounding) is not good those transients are going out through your anode and jet pumps to find ground. So, in theory, with a good multimeter, like a Fluke, you should be able to read small voltage or ampere readings between your boat, the water and or the electrical box. Once everything is properly bonded all of the transients should be flowing on the ground wire.

The other thing you could do is to put in some sort of lift in addition to fixing the bonding issue so your boat is out of the water.

Please keep us posted as to what you find.

 

[lazergeek]

After you get your gounding sorted out a galvanic isolator will help ensure you still dont have an issue too.

 

[zipper]

I like looking at what marine surveyors find. These guys are spot on. This is their electrical section, check out this and the rest.

All about the boat systems and structure

 

[FSH 210 Sport]

@zipper that is an awesome link!

@Julian do you think this link could be added to the FAQ?

 

[zipper]

@zipper that is an awesome link!

@Julian do you think this link could be added to the FAQ?

Yes, thanks, a lot of good information on that site. A favorite of mine since we bought the sailboat 4 1/2 years ago. The survey pictures are descriptive.

Edit: I have referenced/linked their website on threads here in the past. It’s good info.

https://jetboaters.net/threads/electrocution-drowning.34131/#post-549845