Boat Trailer Preventive Maintenance

News & Tips: Boat Trailer Preventive Maintenance
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Damaged tire and rim with grease splattered when the hub hit the highway.

Ever had your boat trailer break down on the highway? Such an event can get ugly really quick — even make the local papers. I've been reassessing my own trailer maintenance program after a friend recently had one of his trailer tires fly loose at highway speed.  

Trailer maintenance is a little mundane, so let's get to the exciting part first. While pulling his aluminum jonboat home, a tire and rim came loose on a quiet, straight, divided highway with only occasional passing trucks. The tire took some crazy bounces, sometimes 12 feet in the air, before catching up with my friend's decelerating truck and boat. The boat trailer was leaning over and riding on the little steel wheel hub. Instead of crashing through their truck's back window, a lucky bounce took the tire under the trailer. The steel hub ran over its own tire and rim, damaging the steel rim in five places. Then the tire ejected sideways — not in a lethal manner across the highway, but off into dark woods where it was hard to find.

As it turned out, his four new 2-inch lug nuts, recently painted to avoid corrosion, had somehow vanished — most likely loosened by someone at an isolated boat ramp, where the locals seem to take issue with out-of-towners fishing their spots. After fishing, a cursory check at the boat ramp would have prevented the entire episode: loose lug nuts could have been tightened. Missing nuts could have been replaced from the other tire or from a box of spares.

A bigger, top-heavy boat might have flipped while leaning that far over, especially on a curve in the road. But the johnboat was 15 feet long, and light. The two anglers were actually able to lift boat and trailer a foot high and barely slide a handy milk crate under the trailer, allowing room for a car jack to operate properly. The tire was changed, but the buddy bearing had impacted the highway and vanished, splattering grease on the boat. Without a spare cap or  duct tape, they wrapped a Ziploc sandwich bag over the open, still-greasy bearings, and eased into the next town without loosing more grease. An auto parts store was open late, that carried bearing protectors and spare lug nuts.

For them, it was a wake-up call that boat owners should carry spare trailer equipment with them. Even a well-maintained trailer can come apart if someone vandalizes it. My friend hadn't lost a lug nut in 30 years of trailering boats, with countless miles on the highway. However, a good record won't stop a fiasco tomorrow. All you can do is employ regular trailer maintenance, cursory checks of the trailer before getting on the road and at the boat ramp, and carry a box of spare trailer parts.

On the Road Again  

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Wheel hub that carries the bearings. When tire came off at high speed, road surface damaged the hub’s outer edge. Photo taken next day with new Buddy bearing.

You can bet that pro tournament anglers carry plenty of spare parts for their heavier boat trailers. These guys log some long highway trips and they have to arrive in time for the starting gun.

Florida pro angler Ron Klys competes in bass tournaments around the Southeast, pulling his rig up and down many an Interstate and country back road. 

"I even carry a complete extra wheel hub, with greased bearings inside," says Klys. "Also a quality spare boat trailer tire, 4-way jack, duct tape, extra bearing protectors, grease gun and extra grease, and a hammer to tap or pry. Also a few road flares and a flashlight, since we pull up and down many a dark road". (It should be noted that flares would have helped slow passing traffic during my friend's recent trailer mishap. Instead, cars were zipping by only five feet away without even changing lanes, while he changed the tire).

"Always carry extra fuses and light bulbs for the truck and trailer," continues Klys. "If the truck lights don't work, the trailer's won't either. If you run a tandem trailer axle, bring heavy duty tie straps to tie the second axle up, if all else fails. Give the wheel bearings a quick shot of grease before making a trip. When filling the truck with gas, I walk around and look for obvious dangers. During pit stops, I feel the trailer hubs for signs of heat. If anything is going to happen, those bearings will heat up first."

More Boat Trailer Tips  

Keep in mind that many trailer boat rigs weigh tons. If the trailer sags far over, it may take a scissor jack to get underneath.        

After a day of fishing, make sure those lug nuts look tight. When you return to the ramp, count your lug nuts and give the tire a push with your foot, watching for a loose tire. Check your trailer ball and hitch for looseness, as well as making sure the safety chains are crossed and attached.

As a hot tip, when parking, make sure your tow vehicle and trailer don't cross the line, giving local law enforcement a chance to tow your vehicle. There are horror stories coming out of Texas these days, of tow vehicles and their trailers removed from Galveston Bay ramps and also North Padre Island. Average cost to reclaim each rig is reportedly $2,500. Even in this era of local communities bending rules to the breaking point to raise cash, having a fisherman pay thousands for a towed vehicle is a serious shakedown. Out-of-state vehicles may be especially targeted. Some tournament anglers today would rather pay the occasional fine for a "lost license plate" than have their vehicle targeted for towing -- or vandalized, for that matter.


Preventive Boat Maintenance Starts at Home   

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Keep a spare hub kit tucked away in your truck or boat for use in a pinch. 

There are many facets to boat trailer maintenance, many of them neglected in our efforts to reach the fish before the Saturday crowd arrives. Neglect and a wrong turn of events could be dangerous — even deadly.

Here's a very basic checklist before getting on the road:  

  • Cross your trailer's safety chains when connecting to the vehicle.

  • Is your trailer tongue jack all the way up, or folded and locked? You don't want to hit a neighborhood safety bump with the wheel down -- trust me on this.

  • Is every lug nut tight? They should be torqued to about 85 pound.

  • Have a secure tie-down strap for the back of the boat, or a pair of transom straps for a bigger boat?

  • Boat trailer tires carry higher pressure than cars; inflate to 50 PSI when cold, or as specified on the tire. Watch for signs of wear, like spider web cracks in the sidewalls. Three additional things to avoid with parked trailers: Keep them out of the sun, off the grass, and don’t leave the trailer sitting in one spot for long periods. All three are hard on tires.

  • Test your trailer brakes (if you have them) by bumping the brakes near your house, not on the intrastate.

  • Are those trailer lights working, even the turn signals?

  • Make sure your trailer ball fits the trailer, seats snugly without debris inside the hitch, and the fastener pin to the truck hitch is secure.  

The short checklist above can save a world of pain on the highway. Proper trailer maintenance is a lengthier subject, of course.

If you constantly fish saltwater, corrosion is a constant enemy of your trailer. Spraying down with a hose after every trip is absolutely necessary. I prefer a solid dunking, however. Returning from the coast, I've found a handy lake ramp offering sweet water. I bury my salty trailer in the lake for at least five minutes, while also running the motor.  

Trailers are notorious for carrying non-galvanized parts — such as U-bolts, nuts, the winch gear, trailer jack and leaf springs. They should all be sprayed with a rust inhibitor. If you get the chance, it won't hurt to double-paint some or all of those trailer parts — they last years longer.

Your trailer runs on tiny ball bearings, and they do require grease. Consider using sturdy marine grease that won't break down when exposed to salt water. Prevent any water intrusion by using bearing protectors that can stay sealed for up to six months, with new grease added by grease gun through a small center nipple. Go easy when adding new grease; too much will pop out the back seal behind the tire, allowing water intrusion — and spraying grease on the tire at highway speeds. That small outer nipple should be covered by a bearing protector cover.    

If you have a self-braking trailer, watch your brake fluid level in the reservoir. Use a quality Dot-3 brake fluid. Brake lines on a boat trailer are thin, hypodermic steel that carries the fluid. They can easily rust, causing a leak that will drain the reservoir and cause brake failure. When replacing brake lines for our 25-foot trailer, I painted primer and then two coats of paint before they went on the trailer. Guess what? No more rust for a few years, even in salt water.

There are weight considerations for towing a trailer. What weight is your trailer rated for? It should not be exceeded. For instance, why fill up your boat tanks with fuel and/or the water reservoir when you still have highway driving ahead? Also, before getting on the highway, be sure to pull the drain plugs or hit the bilge pump for unwanted water. Just 70 extra gallons of fuel is like having two adults riding in your boat, mashing down on your trailer on the highway. That serves no useful purpose. Just be sure you have a quality gas station in mind near your destination. Arriving on the water with the nearest gas station some 50 miles behind you is no joke.