4 Rust forming at microscopic cracks in
this bow pulpit railing, likely due to a combination of stress corrosion and fatigue.
5 Stainless-steel swim platform support
brackets and platform ladder bolts rusting is an example of atmospheric and
immersion corrosion aggravated by the
platform’s core (wood) being damp from
water intruding at the hardware fastenings.
6 The mast step footplate is crumbling
from corrosion perpetrated by stray current
from improper bilge pump wiring.
7 Stainless steel is not recommended for
use in exhaust water-lift fabrication. Wet
exhaust by-products are highly corrosive
and this unit, installed in a boat built in the
Far East, is leaking at every weld, and the
drain plug of an incompatible metal has
wasted away from galvanic activity. When
the plug fails, exhaust water will leak into
the bilge and flood the boat.
8 A bad installation of an aluminum fuel
tank installed low in the bilge and exposed
to bilge water splash. There is no drainage provision for tank surfaces and water
is trapped within tank support structure,
precipitating corrosion. When the tank was
removed, poultice corrosion had destroyed
the bottom panel.
9 Stern-drive gasoline engine exhaust system leaks at manifold and riser are causing
rust to form on surfaces around gaskets.
If water is leaking, so are toxic carbon-monoxide (CO) vapors.
10 Zamac (zinc-coated steel) fitting corroding from atmospheric corrosion. Zamac
is not durable in the marine environment
(OK in freshwater; not in saltwater).
11 Rust staining should have clued the
boat owner to a problem with the valve
control handle, which has now completely separated from the valve; shutoff
will be impossible without another tool.
Emergencies are not the time to go hunting
for the tools.
12 Rust and cracks observed at the welded
ring on this stainless-steel stanchion railing
are the result of weld sickness and stress
13 Stainless-steel prop nut showing a large
void that propagated from a tiny crevice
under attack from crevice corrosion. When
the nuts were separated, their facing surfaces looked like metal lace.
BOATU.S. MEMBERS SAIL INTO
OF UP TO 25%
Now BoatU.S. Members can get $25 off a weekly rental or
a FREE single upgrade from Avis. That’s in addition to your
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number of your choice when making your reservation.
$25 Off a Weekly Rental
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For reservations, visit avis.com/boatus
or call 1-800-225-7094.
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Terms and Conditions: $25 off a weekly rental offer valid on an intermediate (group C) or above car, excluding
groups S and X. Dollars off applies to the time and mileage charges only on a minimum five-consecutive-day rental period.
Single upgrade coupon valid for a one-time, one-car-group upgrade on an intermediate (group C) through a full-size,
four-door (group E) car. Maximum upgrade to premium (group G). The upgraded car is subject to vehicle availability at
the time of rental and may not be available on some rates at some times. A 24-hour advance reservation is required.
Taxes, concession recovery fees, vehicle license recovery fee and customer facility charges ($10/contract in CA) may apply
and are extra. Optional products such as LD W ($29.99/day or less, except in Louisiana $49.99/day) and refueling are extra.
One coupon per rental. Offers may not be used in conjunction with any other coupon, promotion or offer except your member
discount. Coupon valid at participating Avis locations in the contiguous U.S. and Canada. The savings of up to 25% applies
to the time and mileage charges only. An advance reservation is required. Offers are subject to vehicle availability at the
time of reservation and may not be available on some rates at some times. For reservations made on avis.com, dollars off
and upgrade will be applied at time of rental. Renter must meet Avis age, driver and credit requirements. Minimum age may
vary by location. An additional daily surcharge may apply for renters under 25 years old. Rental must begin by 12/31/11.