A couple of years ago the bracket holding the (aluminium engine block) outboard motor on the back of my little sailing cruiser sheared and the outboard (running hard in astern) hopped off across the surface for a couple of feet before disappearing 'neath the briny. Fortunately it was in only few feet of water and I was able within 10 minutes to find it and grapple it back on board. I called my friendly marine engineer for advice and he said 'if you can get it here within the hour we might save - otherwise just throw it in the skip...' True: salt water and alluminium do not go well together - despite the fact that there are any number of alluminium boats. Even on those corrosion is an ever-present problem.
Doug, many years ago I saw a total non classic, a late 60s VW that had been dumped for less than a week in very salty water,[tidal estuary] the crank and gears where visible through the hi magnesium alloy cases. The metal was fine in that short period
Edited by Mal9444, 13 January 2013 - 15:04.