Two rules govern what tools to carry aboard your boat: The bigger the
boat, the more tools you should carry. Likewise, the older the boat,
the more tools you'll likely need. For most pleasure boaters, the
necessary tools are basically the same, with slight variations for a
boat's age, size and engine/drive configurations. We asked industry
professionals and avid everyday boaters who carry tools on board, and
this is the list that ensued:

Duct tape - Guaranteed to stick at speeds up to 200 mph, this
fabric-reinforced tape does everything from securing a piece of stray
molding and attaching fenders to sealing holes or leaky fittings.

Electrical tape - If a wire breaks or the insulation chafes, electrical
tape can mean the difference between driving home under your own power
or being towed.

WD-40 - Spray this inside a wet distributor cap, use it to penetrate a
rusty fitting or lubricate your old rod and reel. Be careful where you
store it, though; this stuff is flammable.

Screwdrivers - Carry small and large slot- and Phillips-head
screwdrivers to fit all screws on board.

Pliers - Carry a pair of standard slip-joint pliers, a pair of
needle-nose with side cutters and a pair of channel-locks. If you have
the space, also include a pair of vise-grips.

Socket set - You can get away with carrying common sockets, but
carrying a set is usually a better idea if you have room. Craftsman
makes sets that include standard and metric sizes. Also be sure you
have a socket that fits your engine's spark plugs and prop nut.

Combination wrenches - Metric and standard combination wrenches (open
on one end and boxed on the other) are essential for on-water repairs.
Craftsman and other companies offer combination wrench sets, and also
include them with a socket set.

Adjustable crescent wrench - Keep a large one that fits bigger nuts
that the combination wrenches will not.

Ball peen hammer - You can always find a use for one of these, even if
it's just to discipline a recalcitrant guest with a thump to the head.

Allen- and Torx-head wrenches - Many newer boats use these fasteners
where hex-head bolts and screws don't fit.

Spark tester - Good for older boats. This takes the mystery - and the
danger of shocking yourself - out of checking for juice at the plugs.

Trailer-tire tools - This is especially important if you have a
single-axle trailer. A spare tire won't do you a bit of good unless you
have a trailer jack and everything you need to change it. Odds are the
tools for your tow vehicle won't work.

The storage space you have on board determines how many tools you can
carry. Be sure you either keep them in a dry space or store them in a
watertight bag or box. That way, your tools will be rust-free and ready
when you need them

Best regards
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