Repair & maintenance guides
Plain-English, step by step, written for owners. Pick your engine to see the guides that apply to it.
369 of 509 guides · page 15 of 16

Tow Ropes, Tubes and Watersports Gear: Inspect, Rig and Retire
Check ski, wakeboard and tube ropes, handles, towable tubes and your boat's tow points before every outing, rig them the right way, and know when to throw gear out. Includes the safety basics (spotter, flag, life jackets, prop and carbon monoxide) that vary from state to state.

Tow Vehicle Maintenance for Boat Owners (Transmission, Differential, Brakes, Hitch)
Keep the truck or SUV that pulls your boat ready for the job: follow the severe-service schedule, protect the transmission from heat, check the rear differential for ramp water, keep brakes, tires, hitch and wiring in shape, and rinse salt off the underside after every saltwater launch.

Tow Vehicle Rear Differential Care: Ramp Water, Milky Gear Oil and Limited-Slip Additive
Backing the truck's rear axle into the water at the launch ramp can pull water into the differential through its vent. Learn how water gets in, how to keep the axle dry, how to drain and read the gear oil, why limited-slip axles need friction modifier, when to change the fluid, and when the differential needs a shop.

Towable Tube Care and Repair: Find Leaks, Patch the Bladder and Know When to Retire It
Inspect a towable tube's bladder, cover, valves, handles and tow point, find and patch leaks the right way, and dry and store it so it lasts. Also covers rider ratings and the damage that means the tube should be retired, not repaired.

Towing a Wide or Heavy Boat: Width Limits, Oversize Permits and When to Hire a Hauler
In most states a boat or trailer wider than 8 feet 6 inches (102 inches) is a wide load that needs a permit, and some loads also need flags, signs, lights, set travel hours or escorts. Learn how to measure your rig, find each state's rules, get the permits and decide when a professional transporter makes more sense.

Trailer Tongue Jack and Coupler Care: Grease, Adjust and Know When to Replace
The tongue jack and coupler take a beating from weight, road grit and launch-ramp dunking. A few minutes of cleaning and grease a couple of times a season keeps the jack cranking smoothly and the coupler locking tight on the ball, and tells you when either part is worn out.

Transom Savers and Motor Supports: How to Trailer Your Outboard or Sterndrive
Potholes and driveway dips put real load on the transom, the tilt system and the engine bracket. Learn when engine makers want a support, why the tilt support lever is not one, how to choose and fit a transom saver or trim-ram support, and what goes wrong when it's fitted badly.

Trim Gauge Reads Wrong or Not at All: Testing and Replacing the Trim Sender
When the trim gauge sticks at full up, reads backward or jumps around, the cause is usually the sender at the engine, a corroded wire or a bad ground, not the gauge. Learn how the sender works, how to test the gauge and sender with a meter, how to adjust or calibrate it, and when replacement is a shop job.

Trim Leaks: When the Motor or Drive Won't Stay Up
Track down why your outboard or sterndrive slowly sinks, trails down on the trailer or leaks trim fluid. Work from the free checks (release valve, fluid level) to hoses, ram seals and internal leaks, and learn when a rebuild or a new cylinder makes more sense.

Two-Stroke Oil Injection vs. Premix: How It Works and How to Check It
A two-stroke engine dies quickly without oil in its fuel, so the oil injection system and its alarms deserve regular attention. Learn how injection and premix differ, what the warning horn is telling you, how to check the system, how to premix safely using your manual's ratio, and the real risks of disabling injection.

Two-Stroke Premix Conversion: Living With an Engine That Had Its Oil Injection Removed
Bought a two-stroke outboard or PWC whose oil injection was removed, or thinking of doing it? Learn how to confirm what was done, mix fuel at the ratio from your manual every single time, label your tanks so nobody forgets, choose NMMA TC-W3 oil and understand the real risks.

Two-Stroke Smoking More Than Usual - Troubleshooting Guide
Tell normal two-stroke smoke from a warning sign, then work through the usual causes in order, from the oil mix and choke to spark plugs, oil injection, carburetor and overheating, and know when to shut down.

Underwater LED Lights: Care, Leaks, Corrosion, Wiring and the Rules
Keep underwater LED lights bright and your hull dry. Learn the difference between through-hull and surface-mount lights, how to clean growth off the lens without damaging it, what to check for leaks, wiring, fusing and bonding, when the boat has to be hauled, and why the lights should not be on while you're underway.

Upgrading Boat Trailer Hubs: Grease-Through Spindles, Oil Bath, Protectors and Pre-Packed Kits
Choose the right hub setup for how you use your trailer, swap in a pre-packed hub kit, adjust it correctly and know when the axle itself is the real problem. Better hubs mean fewer roadside bearing failures and less time with greasy hands.

USCG Documentation Renewal: When, How, What It Costs and How to Avoid Look-Alike Renewal Mailers
Keep your boat's Coast Guard Certificate of Documentation current: how long a recreational certificate lasts (1 to 5 years), the federal fee schedule, renewing directly with the NVDC online, what happens if it lapses, why many states still want registration and a decal, and how to spot the third-party letters that charge several times the real fee.

USCG Required Safety Equipment Check by Boat Length
Walk through your boat and confirm you carry every piece of safety gear the US Coast Guard requires for your boat's length and type, and that none of it is expired or worn out. Missing or expired gear is one of the most common tickets on the water, and it is the gear you need when things go wrong.

Used Boat Paperwork: Titles, Liens, HIN Checks, Bill of Sale and Registration
A practical checklist for the paperwork side of buying a used boat: state title or Coast Guard documentation, checking for liens and theft, verifying the hull ID number, writing a proper bill of sale, the trailer's own title, registering in your name, and transferring warranties and checking recalls. Rules vary by state, so confirm each step with your state agency.

Used Boat Purchase Agreement and Closing: Deposit, Contingencies, Bill of Sale and Who Pays What
A plain-English walk-through of buying a used boat on paper: getting ready before you offer, what the purchase and sale agreement should say, how the deposit is held and when it comes back, survey, sea trial, financing and insurance contingencies, paying off the seller's loan, the bill of sale, closing and transferring the paperwork, and the costs each side usually covers. Practical help, not legal advice; rules vary by state.

V-Drive Transmission Care for Wake and Ski Boats: Fluid, Cooler, Coupler and Shaft Seal
Wake boats and many ski boats put the engine in the stern, backward, and turn the power through a V-drive transmission. Learn how to check and read the transmission fluid, why the cooler and its drain matter in winter, what the coupler and shaft seal tell you, and which noises and leaks mean it's time for a technician.

Vapor Lock and Hot Restarts: Why Your Boat Won't Start After a Stop on a Hot Day
On hot days, fuel can boil into vapor in the lines, carburetor or fuel system after you shut down, so the engine cranks but won't start, or starts and dies after a fuel stop. Learn how to recognize heat soak, restart a hot engine the right way, and reduce the problem with fuel choices, ventilation and line routing.

Vinyl Hull Wraps: Pros, Cons, Prep, Care and Removal
Find out whether a vinyl wrap makes sense instead of paint for your hull, how to prep for it, when to hire an installer, how to wash it without ruining it, and why wraps stop at the waterline.

Visual Distress Signals: Flare Expiry, Storage, Practice and Safe Disposal
Make sure your flares, smoke signals, distress flag or electronic distress light meet the Coast Guard rules for day and night, are not past their 42-month date, and are stored where you can grab them. Then get rid of expired flares the safe and legal way instead of letting them pile up in a locker.

Wakesurf Safety: The Right Boat, Carbon Monoxide, Spotters and Distance
A pre-ride checklist for wakesurfing - surf only behind inboard or V-drive boats built for it, keep riders away from exhaust and the engine off when they board, use a spotter and a short surf rope, stay well away from shore, docks and other boats, and never overload the ballast.

Water in the Lower Unit Keeps Coming Back - Seals and the Pressure Test Explained
Milky gear lube means water is getting past a seal, and changing the oil alone will not stop it. Learn where water gets in (prop shaft seals, driveshaft and shift shaft seals, drain and vent screw gaskets), how a pressure and vacuum test finds the leak, and when to do it yourself or hand it to a shop.
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