Trailer Brakes

[jhol]

Ok, here is what I got

2005 shorlandr trailer, single axle with haudrilic brakes. The kind where the boat slows down because the piston in the trailer hitch actuates the brakes. Anyway recently I am having an issue where the brakes lock up when trying to reverse. I know there is a signal sent on the brake harness from the truck to the trailer as a safety override, atleast I think that is how it works, but recently it is catching. Today at the ramp it worked perfectly fine backing up and then it rocked over the concrete and locked up, I can go forward just fine. But this intermitant problem is getting old quick??? any advice or experience would be greatly appreciated....

[marine_man]

So you have the trailer connector with the 5th pin? If so, I'd make sure that that electrical connection and ground is good to where it ties into the brake system...

marine_man

[jhol]

I will check the ground tonight, is it possible it is something with the piston, it seemed like the last time it would back up just fine then there was a small ridge on the ramp I had to go over and as soon as I would hit the uphill side of the ramp the brakes would lock up.... it was pretty embarrasing, lucky I was the only one at the launch, it took like six times until the brakes did not lock up,,,,,

Yes I use the fifth pin, sometimes when the water is cold I will unhook it and just leave the fifth pin connected so I do not burn out my hot lights with cold water...

[JohnMickish]

The way it works is there is a reverse actuatotor that is enabled when you put it in reverse. This actuator is supposed to prevent the piston from pushing the brake fluid and thus applying the brakes. It is possible that the reverse actuator has bit the big one. First thing to check is that you are getting power to it in reverse by the fifth pin.

[3andadog]

I have the same trailer and have had that problem. Usually the plug is not seated correctly. It did that to me yesterday and I worked the plug a little (big recpticle on a suburban).

I also use the lockout bracket that is on the saftey pin cable, I tape it in place since it will fall out real easy.

[Valv]

Yes I use the fifth pin, sometimes when the water is cold I will unhook it and just leave the fifth pin connected so I do not burn out my hot lights with cold water...

There's you problem.

When you connect just the 5th pin, you loose the ground connector, consequently the lock will not disengage. You need to leave the whole connector attached. It might work sometimes, since it can get ground from the hitch being connected to the truck but it is not always the best way.

Check with a dealer, many trailers have a slot on the side of the actuator where you can insert a d1/2 moon shaped key and will keep the piston from moving.

[PropsterII]

Valv has it. The brakes are working exactly how they are supposed to. On level ground you should be able to back up no problem. When you get on soft ground or backing uphill, that is when the actuator will kick in and apply the brakes. The solenoid works by preventing the hydraulics when you put it in reverse (it's hooked to your backup wire on the vehicle). Assuming your solenoid is working properly it's got to be your connection. Mine doesn't have the solenoid any longer (previous owner took it off), so I just slip the mechanical lockout piece in the slot when I go to back up uphill. Lacking anything you can put in there to prevent the cylinder compressing, you can always disconnect the hydraulic coupler temporarily.

[jhol]

Guys,

Thanks for all the good advice, this HSOforum always amazes me when I have a problem. I will double check the connections and keep all the plugs connected when backing in. I also have the D plug to mechanicaly override so that will always be my back up. Thanks again for all the replies. I am hoping the solenoid is not shot otherwise I will try my mechanic skills soon. Since we are on the subject of trailer brakes how often do you all adjust those brakes, I read in the manual you can adjust them but not sure when or how often this should be done???

Thanks.

[kdawg]

Just in case your problems not the pin, I have a trailer where the breaks are activated by the piston in the hitch as well. When backing uphill, my breaks will almost always activate. I carry a 3/4 inch nut that I will tape within the external slot on the hitch, to prevent the piston from moving backward and activating the breaks. It works slick. Good luck.