Midsummer Boat Maintenance Tips From BoatU.S.
Seaworthy, the newsletter from BoatU.S. that
helps boaters and anglers prevent damage to
their vessels, looked into some of the more common
reasons for on-the-water boat troubles that
“Preventive maintenance will help you avoid
the headaches and keep your crew or fishing
buddies comfortable and safe,” says Seaworthy
Editor Bob Adriance. “So going over the boat’s
systems in the spring is very important. But now
after a couple months of use, it’s time to look at
things again. A midsummer check-up will
ensure you make it back to home port without a
Here are some midsummer maintenance
tips for both power and sailboats:
Through-hulls: Make a thorough check
around any below-the-waterline hole or opening.
Check all through-hulls for leaks and cycle seacocks
to ensure they close properly. If it’s hard to
move the handle, make a note to service it next
time the boat is out of the water. Any hose
clamps should be tight and hose ends secure. A
bilge pump cycle counter is a simple upgrade
and the best early warning system that unwanted
water is coming aboard.
• Engine belts: For inboard engines, look in
areas near the belts checking for evidence of
black dust — a sure sign that engine pulleys
need to be realigned and the belt replaced. Push
on the longest run of the belt — it should not
deflect more than one half inch.
• Engine hoses: Squeeze coolant and fuel
hoses with your hands, looking for softness,
cracks or bulges. Replace any that are suspect.
Wiggle the ends to ensure they are secure and
inspect for any possible chafing issues in the
• Sterndrives: Inspect the folds in the bellows
and replace if they show signs of cracking.
• Sacrificial zincs and anodes: A wasted
zinc is a sure sign of trouble, possibly stray current
at the dock. Ensure all zincs are no less than
half gone — and replace them now if they are.
• Control cables: Look for chafe, splits or
swelling of the plastic jacket — a sure sign the
cable needs replacement.
• Outboard engine mounts: Smaller engines
can sometimes vibrate loose, so re-tighten
clamps and ensure the cut-off switch is operable.
• Hydraulic steering system and trim tabs:
Ensure reservoirs are full. If you have to add fluid,
there is leak that must be fixed immediately.
• Batteries and electrical system: Dead batteries
are often nothing more than corroded connections
— sandpaper can easily clean them up.
With conventional batteries check water levels
and add if necessary. Inspect cables and wiring
for chafe, especially wherever they may pass
through a bulkhead.
• Shorepower cable: Look for burn marks on
the plug ends and the connection to the boat.
Replace both the plug and receptacle immediately
if you find any.
• Head: If your boat has a flushing toilet and
its handle is getting hard to operate, you’ve likely
got calcium buildup. Pour a cup of vinegar into
bowl pumping only once or twice. Let it sit for
one night before flushing with one-fourth cup of
• On deck: Old, stiff, or chafed dock lines
should be replaced. Also check anchor line and
chain shackles and any splices.
• Sailboats only: Look for any broken strands
on standing rigging. You can find them by running
a loose rag up the rigging, which will snag
on any broken ends. Cracked swages are an indicator
for immediate replacement. Contact a rigger
if you suspect a problem. Running rigging
also needs to be looked at — especially the roller
• Trailers: Inspect bearings and ensure they
are well packed with grease. Hydraulic brake
reservoirs should be full. Lastly, check the tires
for wear and ensure lugs are tight.
More checklists are also available at