Trouble-free boating starts before you leave home. In fact it starts with the trailer as David Thornton explains.Often boat owners overlook their responsibility to maintain their trailers in a roadworthy condition. Should your trailer be deemed unroadworthy prior to an accident you might find yourself up for the cost of repairs not only to your trailer, but also for third party damages.
Fortunately, your trailer is not as complex as your car so it is fairly easy to check things out yourself and identify areas that may need professional help.
Trailer Frame: This includes the sub-frame, mudguards, winch post and supporting items such as rollers. The frame of the trailer must be free from any major rust - the integrity of the whole rig relies on the frame being able to support and distribute the weight carried. Start at the coupling and ensure the connection is secure, then follow the drawbar down the frame and check all welds for any cracks. Check all structural beams for rust, especially in the bottom of the tubes, where it usually starts. A potentially dangerous situation can arise where a frame has rust inside the beams. Here the trailer can break without any warning. I have seen a drawbar break clean off due to rust, with the coupling, safety chain and winch post remaining on the car while the sub-frame, including the axles of the trailer were left behind.
Should you drill a hole in your trailer, make sure you repaint it with cold galvanising paint so that the exposed steel is protected from saltwater as much as possible.
Check the mudguards to ensure they are secure to the frame and free from any sharp exposed edges.
All roller brackets and beams that support the hull also need to be pretty strong. If they fail and the boat shifts on the trailer, it can unsettle the trailer enough to make it very unstable.
For many people, towing on the road is often an afterthought, but this is the area of most risk simply because of the proximity to other users. If your 1500kg trailer laden with your boat suddenly breaks free on the road you can imagine the problems.
Extra stress such as sudden braking, potholes or speed humps may be all that is needed to finally bring you to grief.
Once you are happy that the frame is in good condition then move on to the suspension, brakes, hubs and tyres.
Suspension: Springs that are extremely rusted will usually break - rust usually comes off in large, sheet-like chunks, which reduce the spring’s ability to absorb shocks from the road. On load sharing type springs found in tandem or triple axles, ensure the bushes inside the shackles are greased so that they can pivot and transfer the load. The bolts that mount through the bushes usually have nipples on them to facilitate greasing. Look for badly rusted or broken U-bolts or cracks where the springs mount to the trailer frame.
Replacing these components is not terribly expensive - if you have to replace rusted suspension, invest in galvanised replacements.
If you find the whole lot is shot, then I recommend ALKO torsion axles as a replacement. When I replaced all the rusted triple axles and springs on my trailer I converted it to a tandem using the 2.5 tonne axles and was impressed at not only how effective they are, but also by the time taken to get it all completed.
Brakes: Braking ability and performance are serious matters. If your trailer has brakes, make sure they work. No matter what type of brakes you have on your trailer, winter is the time to take the wheels off and have a look.
There are only two types of brakes found normally on trailers, cable and hydraulic.
Cable Brakes: It’s vital to adjust cables on a regular basis. If they’re too slack brakes will not activate with any force.
To tighten the cable, adjust the tensioner (normally found near the front of the trailer). Ensure it’s not rusted and can be turned easily. The cable should be just tight enough so that if you pull it by hand the pads actually push against the disc.
Also check the brake discs to ensure they are not badly rusted. Lightly spray a 50/50 mix of Turps and Linseed oil onto the brake discs regularly to prevent rust build-up. It’s best to do this while they are warm.
Hydraulic Brakes: Smaller boats up to two tonnes have override brakes (where the hydraulic master cylinder is located just behind the trailer coupling). Ensure this is full of fluid, the cap is not leaking and look at the copper lines and fittings for any sign of weeping.
Check the brake caliper to ensure it will release pressure off the disc once the brake effort is reduced. Check the slide pins, which allow the caliper to move from side to side. This is part of the self-adjusting properties in all disc calipers.
On most older trailers, the bolt that holds the caliper to the axles will fit inside the slide pins. Slide the caliper body side to side for 3mm or 4mm. If you can’t move the caliper, remove the pins, clean or replace them. I always regrease them with a product called Neva Seize from Repco.
Replace low brake pads with new ones. To change the pads you must also push the piston back inside the caliper. The best way is to place a large G-clamp onto the back of the caliper, open the bleed nipple and then, using an old pad to push against the piston, slowly wind the clamp up and push the piston back into the caliper housing. The old fluid will be expelled and this should be replaced when you bleed the brakes. Remember also to only have one wheel apart at a time.
If there is any air in the fluid line then your brakes will also fail as air bubbles will compress as the pressure comes on. Although a two-man job, bleeding the brakes is easy.
Use new brake fluid, top up the master cylinder, and attach a clear plastic hose over the bleeder at the top of the caliper furthest away from the master cylinder. Put the end of the hose into an old 500ml Coke bottle. Pump the master cylinder with the hand brake handle. Get someone to pump it up till it feels firm, crack the bleeder, and, as the fluid flows out into the bottle, look for any bubbles. This happens pretty quickly so you only need to crack the bleeder for about a second. Finally, close the bleeder and then repump the master cylinder, topping up with fresh fluid as it goes down. Repeat this a couple of times and then move onto the next wheel in the line.
Over time, brake fluid absorbs moisture and this greatly reduces its ability to maintain the pressure required for good braking. All brake fluid needs to be flushed every two years in cars so I would also recommend the same for your trailer. A 500ml bottle will do almost all trailers and costs around $20.
While the wheel is jacked up, rotate the rim and feel for noisy wheel bearings (the replacement of these has been covered in previous issues) then pump them up with fresh grease.
Trailer Lights: Often trailer lights prove faulty, especially when boats are used for the first time after they have been sitting for a while. The culprit is usually corrosion of the light sockets, damaged wiring and poor connections. With the price of new LED style sealed lights becoming cheaper it is a good idea to replace bad lights rather than fix them, however, beware of cheap versions. There is a new range of Hella LED trailer lamps just released - they are inexpensive and of excellent quality.
Once it takes hold, corrosion is difficult to get rid of so take the time to get the lights right the first time and you’ll have years of trouble-free operation. If you use the Submersalite brand then a good idea is to tin the wire ends with solder before you push them through the rubber seal. Once the wires are in place, coat them lightly with grease to help prevent bad connections. Spray CRC, Inox or WD40 onto globe holders to keep saltwater at bay. Once a lens is cracked, water will soon get in and prevent it from operating.
Tyres: Give tyres, including the spare a good look over. Any splits in the sidewall area will mean the tyre will burst at soon as it gets hot. Also jack the wheel up and rotate the tyre. If it’s a heavy rig this will help eliminate a flat spot when the boat is sitting for longer than a few months. Use a pressure gauge to check if they’re pumped up to the correct pressure. If they’re a bit flat this will actually help a leak become established due to the flexing of the tyre on the rim causing the sealing bead to get out of shape. Note also that inner tubes in your tyres will actually cause them to fail due to heat.
Remember that even though you might not use your boat over winter, this is no reason to forget it. Even starting your boat up and running its motor for 10 minutes every month will pay off in the long-term.
Fortunately, your trailer is not as complex as your car so it is fairly easy to check things out yourself and identify areas that may need professional help.
Trailer Frame: This includes the sub-frame, mudguards, winch post and supporting items such as rollers. The frame of the trailer must be free from any major rust - the integrity of the whole rig relies on the frame being able to support and distribute the weight carried. Start at the coupling and ensure the connection is secure, then follow the drawbar down the frame and check all welds for any cracks. Check all structural beams for rust, especially in the bottom of the tubes, where it usually starts. A potentially dangerous situation can arise where a frame has rust inside the beams. Here the trailer can break without any warning. I have seen a drawbar break clean off due to rust, with the coupling, safety chain and winch post remaining on the car while the sub-frame, including the axles of the trailer were left behind.
Should you drill a hole in your trailer, make sure you repaint it with cold galvanising paint so that the exposed steel is protected from saltwater as much as possible.
Check the mudguards to ensure they are secure to the frame and free from any sharp exposed edges.
All roller brackets and beams that support the hull also need to be pretty strong. If they fail and the boat shifts on the trailer, it can unsettle the trailer enough to make it very unstable.
For many people, towing on the road is often an afterthought, but this is the area of most risk simply because of the proximity to other users. If your 1500kg trailer laden with your boat suddenly breaks free on the road you can imagine the problems.
Extra stress such as sudden braking, potholes or speed humps may be all that is needed to finally bring you to grief.
Once you are happy that the frame is in good condition then move on to the suspension, brakes, hubs and tyres.
Suspension: Springs that are extremely rusted will usually break - rust usually comes off in large, sheet-like chunks, which reduce the spring’s ability to absorb shocks from the road. On load sharing type springs found in tandem or triple axles, ensure the bushes inside the shackles are greased so that they can pivot and transfer the load. The bolts that mount through the bushes usually have nipples on them to facilitate greasing. Look for badly rusted or broken U-bolts or cracks where the springs mount to the trailer frame.
Replacing these components is not terribly expensive - if you have to replace rusted suspension, invest in galvanised replacements.
If you find the whole lot is shot, then I recommend ALKO torsion axles as a replacement. When I replaced all the rusted triple axles and springs on my trailer I converted it to a tandem using the 2.5 tonne axles and was impressed at not only how effective they are, but also by the time taken to get it all completed.
Brakes: Braking ability and performance are serious matters. If your trailer has brakes, make sure they work. No matter what type of brakes you have on your trailer, winter is the time to take the wheels off and have a look.
There are only two types of brakes found normally on trailers, cable and hydraulic.
Cable Brakes: It’s vital to adjust cables on a regular basis. If they’re too slack brakes will not activate with any force.
To tighten the cable, adjust the tensioner (normally found near the front of the trailer). Ensure it’s not rusted and can be turned easily. The cable should be just tight enough so that if you pull it by hand the pads actually push against the disc.
Also check the brake discs to ensure they are not badly rusted. Lightly spray a 50/50 mix of Turps and Linseed oil onto the brake discs regularly to prevent rust build-up. It’s best to do this while they are warm.
Hydraulic Brakes: Smaller boats up to two tonnes have override brakes (where the hydraulic master cylinder is located just behind the trailer coupling). Ensure this is full of fluid, the cap is not leaking and look at the copper lines and fittings for any sign of weeping.
Check the brake caliper to ensure it will release pressure off the disc once the brake effort is reduced. Check the slide pins, which allow the caliper to move from side to side. This is part of the self-adjusting properties in all disc calipers.
On most older trailers, the bolt that holds the caliper to the axles will fit inside the slide pins. Slide the caliper body side to side for 3mm or 4mm. If you can’t move the caliper, remove the pins, clean or replace them. I always regrease them with a product called Neva Seize from Repco.
Replace low brake pads with new ones. To change the pads you must also push the piston back inside the caliper. The best way is to place a large G-clamp onto the back of the caliper, open the bleed nipple and then, using an old pad to push against the piston, slowly wind the clamp up and push the piston back into the caliper housing. The old fluid will be expelled and this should be replaced when you bleed the brakes. Remember also to only have one wheel apart at a time.
If there is any air in the fluid line then your brakes will also fail as air bubbles will compress as the pressure comes on. Although a two-man job, bleeding the brakes is easy.
Use new brake fluid, top up the master cylinder, and attach a clear plastic hose over the bleeder at the top of the caliper furthest away from the master cylinder. Put the end of the hose into an old 500ml Coke bottle. Pump the master cylinder with the hand brake handle. Get someone to pump it up till it feels firm, crack the bleeder, and, as the fluid flows out into the bottle, look for any bubbles. This happens pretty quickly so you only need to crack the bleeder for about a second. Finally, close the bleeder and then repump the master cylinder, topping up with fresh fluid as it goes down. Repeat this a couple of times and then move onto the next wheel in the line.
Over time, brake fluid absorbs moisture and this greatly reduces its ability to maintain the pressure required for good braking. All brake fluid needs to be flushed every two years in cars so I would also recommend the same for your trailer. A 500ml bottle will do almost all trailers and costs around $20.
While the wheel is jacked up, rotate the rim and feel for noisy wheel bearings (the replacement of these has been covered in previous issues) then pump them up with fresh grease.
Trailer Lights: Often trailer lights prove faulty, especially when boats are used for the first time after they have been sitting for a while. The culprit is usually corrosion of the light sockets, damaged wiring and poor connections. With the price of new LED style sealed lights becoming cheaper it is a good idea to replace bad lights rather than fix them, however, beware of cheap versions. There is a new range of Hella LED trailer lamps just released - they are inexpensive and of excellent quality.
Once it takes hold, corrosion is difficult to get rid of so take the time to get the lights right the first time and you’ll have years of trouble-free operation. If you use the Submersalite brand then a good idea is to tin the wire ends with solder before you push them through the rubber seal. Once the wires are in place, coat them lightly with grease to help prevent bad connections. Spray CRC, Inox or WD40 onto globe holders to keep saltwater at bay. Once a lens is cracked, water will soon get in and prevent it from operating.
Tyres: Give tyres, including the spare a good look over. Any splits in the sidewall area will mean the tyre will burst at soon as it gets hot. Also jack the wheel up and rotate the tyre. If it’s a heavy rig this will help eliminate a flat spot when the boat is sitting for longer than a few months. Use a pressure gauge to check if they’re pumped up to the correct pressure. If they’re a bit flat this will actually help a leak become established due to the flexing of the tyre on the rim causing the sealing bead to get out of shape. Note also that inner tubes in your tyres will actually cause them to fail due to heat.
Remember that even though you might not use your boat over winter, this is no reason to forget it. Even starting your boat up and running its motor for 10 minutes every month will pay off in the long-term.