The Ultimate Boat Trailer Maintenance Guide

The Ultimate Boat Trailer Maintenance Guide


1. Intro

The best time to maximise the benefits of maintaining your boat trailers are when its brand new, before corrosion has started, before threads start to seize up, and bearings seize through lack of grease and so on.

2. Bearings

Lets start with the wheel bearings; failure in which is extremely inconvenient at best and can be disastrous. Has the supplier packed them with grease and do they have bearing ‘buddies’ fitted to maintain the grease under a slight pressure in order to prevent sea-water ingress?  (AakronXpress does this) If not done already get it done NOW!

3. Wheels

While you’re at the wheels, check the wheel bearing for adjustment. The wheel should not clunk when pushed and pulled sideways, nor should it be too stiff to spin a couple of turns  when suspended. If you hear ANY grinding noise get them checked by a mechanic promptly, or simply replace them. They aren’t as expensive as a failure in the middle of no-where.

4. The Frame

Now lets look at the parts of your ‘fully galvanised’ trailer that aren’t actually galvanised at all. For a start the wheel studs are made from hi tensile steel and can’t be galvanised or they would lose their strength. So spray some “Lanocoat” (obtainable from Supercheap Auto, Repco, and similar stores) over these, front and back several times a year.

5. Winches, Winches, Winches

Now have a close look at you winch; at least the gears wont be galved (that would clog up the gears with zinc) and quite often the whole unit is only zinc plated. You can tell zinc plating by its very silvery, slightly blue look where as hot dipped galved products are slightly duller and not so bluish, even when new. So spray these parts with Lanocoat too.  Obviously greasing the gears makes sense not only for protection but also you will find dry gears make winching in your boat a lot harder, and they wear out much faster.  Unwind the strap or rope completely and spray the inside of the drum. This is very prone to rusting as the strap retains the salt water it picks up when you retrieve your boat, and the salt just keeps eating away at the innards of the drum forever unless you protect it. If you want to be thorough you should run out the strap and rinse it with fresh water after every outing, but who is that good?

When older, check the outer few cm of the strap where it is exposed to sun damage and cut away any doubtful fabric. Think what a break here could mean if it occurred as you wound in your heavy boat up a steep ramp!

6. Jockey Wheel

Check out the jockey wheel too; many are not hot dip galved so give them a good wash  after use and when dry spray with Lanocoat. Grease the winding  gears inside once a year to keep the unit working smoothly.
Now have a close look at ALL the fastenings, U-bolts etc. If the supplier hasn’t already greased them (AakronXpress does) consider removing and greasing the critical ones before they seize up with corrosion. The ones you may need to adjust such as the roller height U-bolts and possibly the winch post/jockey wheel position U-bolts are the best candidates. If you notice the silvery blue of zinc plated nuts or bolts replace them immediately while you still can because these will rust mercilessly.

As you probably already know most trailers die from the inside out. So its very important to flush any salt water out of the main frame and cross members. With the trailer on a bit of a slope you can generally hose fresh water down the length of the main beams. If possible feed a hose with a slim, old-style spray nozzle set to a wide fan down the frame. Leave the trailer on a slope to let all the water to drain out completely. Remember;  for rusting to occur you need iron + salt + water + oxygen. Cut out water and salt and you are covered. The cross frames are generally more difficult to flush but if you look underneath you will see drain holes in the middle or at each end. The only thing you can do is to force a blast of fresh water into these holes then let them drain. For both the main beams and the cross members adding  a “Salt-away” rinse after the initial flush is a big step forward too. The units are only about $50 and available from most chandlers.

7. Mudguards

Now mudguards: while not as critical as frames these guys often rust badly from the underside only, due to salty mud and sand sitting there from your last trip to the beach. So always hose thoroughly UNDER the guards and when dry, a blast with the Lanocoat can is a good idea.

8. The Springs

All modern boat trailer springs are hot dip galved so last better than they did in the ‘good old days’. Unfortunately the friction they experience as you bounce along the road soon wears off the protective galvanising between the leaves so its worth sloshing some old engine oil over them regularly to delay the loss of zinc. And the springs will work better and quieter.

9. Bolts

Check the critical bolts at the beginning and end of each season. These are firstly: the bolts holding the tow-ball coupler in place should be hi-tensile and double lock-nutted for security, especially the foremost pair. Check they are in place and tight. Now have a look at what’s holding the axle in place. Often the axle is clamped on top of the springs to help keep the boat as low as possible. This practice means that the U-bolts securing the axle to the springs are critical as a failure would release the axle with disastrous results. Such U-bolts should have double (lock) nuts and you should check these from time to time to ensure they are in place and locked together. Don’t over tighten as a stripped thread means the U-bolt and its nuts must be replaced.

10. The electricals

Finally the electrical stuff: Modern LED lights such as on all AakronXpress trailers are safe to submerse and need no maintenance. However the wiring can get damaged leading to lights failing, so watch out for any point of chafing and if it occurs protect the damage with electrical tape or cut and rejoin using waterproof joiners from any electrical wholesaler. The joiners have a built-in coating of resin which seals the cable as you apply heat from a hairdryer or hot air gun. You should avoid letting salt water get onto the 7 pin connector to the car power as these are not water-proof. Any salt water in there will cause havoc. You can protect the plug a little by spraying the wiring inside with Lanocoat or you could try embedding the interior in silicone sealant if you have to submerge your whole trailer.

11. Rust

As you trailer ages and signs of rust start to appear you can slow down the damage by wire-brushing to clean steel and degreasing with MEK, toluol etc then immediately spray on some “Cold Galv” zinc rich paint. This only works on clean FRESHLY prepared iron. Get the highest zinc content you can find. You will see this on the can label. Anything over 75% is good but lower grades are ineffective so don’t waste your money.

Happy boating!