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Severe Electrolysis Charging System Inoperative

J

John Bartz

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" After fishing last weekend,

" After fishing last weekend, I went to start my '95 40HP Evinrude for the return trip but the battery was dead. It is a new battery and was fully charged the night before. When I got it home I noticed that the lower unit was caked with a white salt-like substance which started to eat away the paint.
All the electrical connections at the engine and battery look fine. Where do I start to look for the problem? "
 
" I might be some help if you

" I might be some help if you could tell me more about your boat and motor. Is your boat aluminum?
Tiller or console? Are you in salt water? What other items, if any, are running off your starter battery? "
 
" Its a fiberglass boat, runni

" Its a fiberglass boat, running in brakish water,and it's a console electric start. Other items running off the starter battery are the livewell pump and a depth finder.Is it possible that the charging system is grounded and not producing enough amps to charge the battery? If so, would that cause the reaction at the lower unit? "
 
" See JoeReeves suggestions on

" See JoeReeves suggestions on checking the rectifier (09/07)under "1985 Evinrude 90HP Battery wont hold charge"

If you have a voltage leak (short) it might enhance the corrosion you are speaking of, but it is probably not the cause. Even with the fiberglass boat you are still putting a large amount of metal into a very good electrolyte. The trick is to make the motor's lower unit or outdrive as impervious as possible so that it can't conduct. If you paint it with metal based paint, or with metal based anti-fouling paint, you are enhancing conductivity. If that is what happened, you should get that paint off the lower unit and replace it with outboard-outdrive paint and then coat it with a sealer specifically designed for outboards and outdrives. If there is no anode designed for your model, get a teardrop shaped zinc and bolt it to the top of the cavitation plate, near the rear. "
 
" The paint on the lower unit

" The paint on the lower unit is original and has been fine for the two years that I've had the boat. The corrosion occurred during one outting in which the boat was in the water for six hours.
The motor has 3 zincs, two on the cavitation plate and one on the motor mount. They are caked with a white salt-like substance. I plan to replace them & paint the lower unit but feel that something is wrong with the electrical system causing an acceleration of the corrosion process.
The white "scurge" has eaten the paint off the leading edge of the gear housing and started on the bottom edge of the motor mounting bracket.
Has anyone had this problem, seen it, or have an idea what's causing it? "
 
Start a new discussion with t

Start a new discussion with the high points of what we talked about. See if Sparky or Joereeves can give you an easy answer.
 
" I have a 1987 Evinrude, 90hp

" I have a 1987 Evinrude, 90hp on a 18ft fiberglass bass boat. 3 years ago I had new steering cable installed. Since then, I have had to put in a new battery each year. This last year, I removed the battery at winter and used it in a pick-up and it did fine. I put it back in the boat last weekend, took off for the lake, and it wouldn't start. Battery was dead. I was able to jump start it, went out for a couple of hours. Put it on the trailor and tried starting it to make sure all was okay, and it wouldn't start. Dead again. I have a live well, and fish finder although I didn't use the live well. I have no idea where to start looking. Don't have a manual to verify the wiring is run correctly. Any help is appreciated. "
 
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