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Trailer maintenance

2011 July 19

Don't let a bum trailer keep you and your boat off the water

J ohn Kain has seen plenty of boat trailer tongues bent like rubber under a hot sun. He has witnessed broken axles resting on launch ramps, and the inevitable flat tires that dampen the celebratory mood at the start of each season.

"It's all about maintenance," says Kain, owner of The Boat Shop in Marblehead, Massachusetts, where each year he maintains or repairs about 50 boat trailers. "Trailers are things most people usually don't think about until it's time to use them. A lot of times the trailer sits under the deck, out of sight and forgotten about. The 23-foot boat sitting on it still has the plug in, and of course it fills up with thousands of pounds of water, a far heavier load than the trailer was made to take."
As boating season ramps up in the northeast, Kain anticipates plenty of knocks on his shop door, mostly customers who can't start their engines or are experiencing difficulties with their trailers. It doesn't have to be this way. Although Kain certainly isn't complaining about the flurry of business, he knows how to prevent such hassles and is willing to share that knowledge. Let's call it Boat Trailers 101.

Here are a few tips from a professional. First of all, if the trailer wheels won't rotate, don't force them. As Kain puts it, "If you move the trailer and the wheels grind, it means the bearings are probably bad. How many times have you seen somebody pulling a trailer down the street and it's skidding the whole way? The bearings rust up a bit during the winter and it's possible to loosen them, but not like that."

Instead, Kain suggests jacking up the trailer and manually attempting to spin the wheel. If it won't budge, pop off the hub with a screwdriver and inspect it. A substance resembling black pepper is often present­-a telltale that the bearings and cones need grease or replacement. If the grease appears milky, it probably has been compromised by water, so repacking the bearings is essential.

"You can do it yourself," says Kain, noting that bearing replacement kits are relatively inexpensive­-under $15.

Don't use lubricants like I Can't Believe it's Not Butter, despite what you may have read in publications written for boaters on a budget. Trailers require waterproof marine bearing grease, which usually comes packaged in a tube. Apply it by hand. You can pack it carefully into the bearings with a frosting knife.

When that's done, take a close look beneath the trailer. In other words, get down on your hands and knees to visually inspect the axle or axles. If the wheels are tilted, it could be a sign of a bent spindle, cracked axle or broken spring.

Inspect the tongue for rust and wear. Trailers are made to carry specific loads. If the boat has been filled with water or lots of gear for six months, there's a chance the trailer is weakened. Don't forget to pull the seacock plug before storing the boat for the winter. It sounds like a no-brainer, but Kain's experiences suggest a different story. Trailer tongues are known to collapse at the most inopportune moments. Check the tongue jack for wear as well.

Examine the leaf springs. When rusted, these metal bands begin splitting apart and it's difficult to judge when they might give way. Kain suggests leaving that part of the inspection or repair to a professional.

Test the lights. If the connectors are corroded, clean or replace them. When backing into the water, leave the connectors undone, which will allow them to dry faster.

Check the winch and especially the rope. Ultraviolet rays tend to break down rope fibers. Besides, trailer winch ropes are seldom given time to dry properly because they are almost always wound onto the winch.

"You can get hurt if the rope breaks and the trailer lets go and you're standing on the ramp," says Kain. "And you can imagine what might happen if it let go on the highway."

Injuries can also occur when boat owners lean forward while cranking the trailer winch. Should the lock slip, the weight of the boat could force the winch handle to rapidly spin backward. Read this scenario as black eyes and busted teeth. The general advice: Don't put your head too close to the winch handle.

Before moving the boat from the trailer, inspect the rollers. According to Kain, worn rollers that are down to the metal can act like pizza cutters on the bottom of your boat. "I've seen it," he says. "It's not pretty."

When all these parts are given the OK, don't drive off until you've inflated the tires to their proper pressure. "Flat tires are probably the biggest thing I see with trailers," says Kain. "When people put a trailer in their back yard, they tarp it and forget it. The tires are in contact with the ground for the winter and that can cause problems."

Don't forget to examine the tire tread. Baloney skins won't do you much good on a slippery launch ramp. To check the tread, use the penny test. Insert a penny in the tire groove. The tread should touch the top of Abe Lincoln's head.

If possible, before storing the trailer, jack up the frame, remove the wheels and let the hubs rest on cement blocks. Lubricate the lug nuts and bolts with a silicone spray like WD-40 or coat them with Vaseline.

Risking oversimplification, here are a few more suggestions: Wash the trailer every time it has been immersed in saltwater; make sure the ball hitch is backed up by chains, the hooks crisscrossed to prevent bounce; use tie-down straps, especially inexpensive ratchet-style webbing to secure the boat; tarp the boat to shade trailer tires and reduce rotting from the sun's ultraviolet rays.

If on the highway, bring along a trailer emergency kit with spare wheel, lug wrench, grease, extra line, wheel chock and road flares. As one mechanic put it, the only certainties are death, taxes and trailer corrosion. By following these maintenance tips, you'll have better odds of delaying the latter, which means more time on the water, and that's what it's all about.