Trailer Brakes
 

Hoping someone with knowledge of trailers and brakes can help me out. Just had the brakes replaced last fall from drums to disk. The brakes haven't worked for a long time, as they were totally rusted. So when I returned home, and when backing the rig up, the trailer brakes locked! I tried playing with the reverse free wheel mechanism, but that didn't work. The brakes are hydraulic, the master cylinder is original.

Any ideas? I am trying to save myself a trip back to the marina. Should I try bleeding the brakes and see if that helps? Or is the master cylinder shot?

Fixx
 

if going forward they work fine for stopping you will need to install a reverse lockout solenoid which cuts the pressure going to the calipers while backing up...it goes between the master and the brake line and you will need to replace the trailer connector from a 4 pin to a 5 pin and wired into your reverse light circuit..http://www.google.com/search?sourcei...32a671eaae94dd

it they are still locked up trying to go forward then when they installed the calipers the didn't drill out the master.. if you look at the master and where the brake line is attached to their should be a brass fitting..if you remove the brake line and remove that fitting you will notice the tiny pin hole in the male end of the fitting,,You will need to drill out the center of the fitting to the size the mfr of the brake caliper recommend and that will take care for the calipers form being locked up going forward..

Drum brakes master cyl. are different than M/C for disc. You can modify to convert as above. Disc brakes will always lock up in reverse without the a locking solenoid or a lock out lever (as long as it locks out before the brakes catch), unlike drum brakes that can be overridden in reverse. The harder you push, the harder they brake.

Thanks for the answers. Would it be easier to just replace the M/C with one made for disk brakes?

No,,, you still need the reverse lockout solonoid and change to 5 wire flat plug from 4 if your not already using the 7 wire round.

One last thing to keep in mind,,,, after coming to a complete stop, you will need to roll forard a few inches to release the brakes before putting it in reverse and backing up

If you install a solenoid, do yourself a big favor and buy the deluxe model. It's not much more. Then you don't have to do the roll forward and put in reverse before the trailer brakes kick in. Plus that's almost impossible to do if backing uphill.

If it's a drum brake master cylinder you have to remove the residual valve, unless the shop that did the drum to disc did it for you. In addition to the lockout solenoid.