Sounds like stray current causing faster than normal sacrificing of the
anode. IMO, best solution is to raise your OB out of the water.

You should also report the problem to marina management and to adjacent boat
owners so they may take appropriate action.

Butch
"Tom" wrote in message
...
I bought a new SeaPro with a 200 Yamaha FI in March and keep it on a
trailer in an enclosed storage building. On weekends I launch and
leave it in the water until Sunday. The trim tab is a sacrificial
anode and is deteriorating rapidly - lots of pock marks. I've done
some searches and found sites on what electrolysis is but haven't
found a site that describes where the problem can originate or how to
correct for it. The dealer felt there was a charge in the water but
also suggested I turn off the Perko every time I dock and tilt the
motor out of the water in case the problem was caused by something
internal. I would appreciate any advice anyone may have. I have built
a temporary pier with power but all power lines are above water and in
conduit (pier is on 4 X 4 treated pilings and I usually dock the boat
15 -25 feet from the pier. There is a power service pole approx. 20
feet from the waters edge and has a grounding rod. Neighbors have
electricity on their piers but none are within 70 feet or so. I have
plugged in my on board battery charger overnight on a couple of
occasions when the boat was in the water. The boat has 3 batteries,
trolling motor, VHF, GPS, Hydraulic Jack Plate (Aluminum), Electric
Trim Tabs, on board 3 bank charger and aerator. That's about all I
know of that could affect it but would be happy to provide any other
info if someone has any thoughts on what could be causing it and what
I can do to stop it. I can raise and tilt the motor completely out of
the water and turn off the Perko switch each time but that's a pain in
the rear (not to mention I'm prone to forget). Thanks in advance for
any advice you might have. Take care.

Tom..................