Help w/04 trailer, keeps locking up w/o boat?

[Stritt]

03's have the same problem. The old actuactors (sp?) did not seem to be as sensitive as the new ones. Like mentioned earlier, you can reverse the plug and activate the reverse lights and lockout. Not great for night driving though. Going down big hills + no boat weight = Bucking Bull. A tandem trailer is even worse. Looks like the kids with cars that have the ability to "bounce" their cars.

As to trailers not designed to be driven empty.............Nice try.

[NeilM]

This isn't a MasterCraft Trailer problem. It's a problem with all surge brake trailers, made worse by disk brakes.

I just duct tape a manual lockout into place so the brakes won't come on when the trailer is empty.

[captkidd]

If all else fails (IAEF):

Since the backup solenoid is electrically activated, why not just install a switch that sends electrical current to the solenoid to close it when trailering without a boat? This could be as simple to install as a set of fog/driving lights. The same wire that provides the current from the backup lights to the trailer could be used. A rocker switch could be installed in the vehicle to "activate" the system, but some sort of "relay" would be required to prevent the current from flowing back to the backup lights (sorry, I'm electronically challenged so I'm not sure what type of device would be required to do this). The cost should be less than $20 and the only downside would be not having any trailer brakes when the system was activated, but this shouldn't be a problem because the trailers for many smaller boats don't even have brakes.

[JimN]

You could use a relay and switch, but you have to remember to turn it off, so a lighted switch is good here. The relay has a terminal for normally closed, which would let the reverse lights work as they normally do. Latch the relay and it doesn't matter if you go into reverse, there won't be a short since normally closed terminal goes nowhere at that point.

[Mag_Red]

Originally Posted by JimN

You could use a relay and switch, but you have to remember to turn it off, so a lighted switch is good here. The relay has a terminal for normally closed, which would let the reverse lights work as they normally do. Latch the relay and it doesn't matter if you go into reverse, there won't be a short since normally closed terminal goes nowhere at that point.

Actually that is what I did! Only I disconnected the regular backup lead to the harness. The only inconvenience is I have to remember to hit the switch when I am backing up. But on the way to the ramp , with an empty trailer, hit the switch, and no more embarressing trailer bouncing.

[JerryW]

There is another fix. I had the same problem with a 2002 double axle trailer. Partly due to warped rotors, but also due to the brakes being too "strong" for an unloaded trailer. You can buy adjustable, in-line brake proportioning valves, and install it. They are often used on hot rods, customs, race cars, etc, especially when new brake systems are installed on an older vehicle, or a mix of disks and drums used on a vehicle. There is an adjusting knob tht you can use to control the braking force.

There are also non adjustable "valves" that limit or slow down the flow of fluid out of the master cylinder. With an empty trailer this causes the brakes to come on slower and not grab as much. With the boat on the trailer, there is enough weight pushing against the master cylinder that the brakes come on quick enough and strong enough.

[KevinZinser]

After my trailer bounced like crazy, and I backed my trailer down a ramp starting 700 yards away because I couldn't pull it down the hill forward, I came up with a legitimate fix.

Take your old 4-prong wire harness and saw through the black plastic portion, cutting off one male and one female wire piece. Take one wire and connect it to the tow vehicle power, and take the other wire and splice it (easliy done with the blue wire splicing clamps) to the brake actuator/master cylinder line. There are three blue wires going to the trailer wiring harness...swing away the tounge and trace the one blue wire from the master cylinder to the end of the wiring harness.

When you tow the trailer without the boat, plug this new 6th wire in, and turn on your lights. This will send power to the master cylinder and lock out the brakes, while allowing all other lights to work properly (unlike the "T" solution). You will know if it is wired correctly if when you plug the 6th wire in, you hear a faint "click" which is the master cylinder disengaging.

The only problem I have found is that when you plug the 6th wire in, you are sending power to the brakelights as well. The brakes won't engage, but the lights are on. If this bothers you, place a simple waterproof switch in line with the brakelight wires and turn them off when your 6th wire is plugged in.

More to the point though...I have seen many questions/complaints about this. How about a real fix to this problem, instead of this jerry-rigging?

[georgea0731]

I talked to Mark, Tech Support at the factory. He said thay have a small o ring like item, orfaset (sp) that can be put in the line to help reduce the pressure. He said to contact your dealer and ask them to order part number, 650680. He said putting it in the line was easy, but you would have to bleed the brakes afterwards.

I recommended he come online and publish this official Mastercraft solution, but I don't think he thought it was a good idea.

Good luck,
I hope your dealers know about this too.

[mckay4]

I fought the same problem on my 2002 X-9 trailer. Dealer installed a new master cylinder with no improvement. I finally ended up pulling the unit out of the tongue and adding a 1/2" ID X .125" thick stainless flat washer to the end of the spring that the cable clip is on which added some additional preload to the tongue. This makes it a little harder to assemble, but worked great for me. It completely eliminated the bouncing when stopping empty and did not affect the stopping ability with the boat loaded. Let me know if you need more detailed instructions.

[rwoznock]

Sorry for the threadjack but I have a 1996 dual axle trailer that doesn't have a reversing selinoid. (and it is such a pain to use that spacer that keeps falling out) Does anyone know if one can be added to my trailer or do I need to replace the coupler?