BajaRunner

I have the surge brakes on a tandem axle trailer, and just started noticing a big CLUNK when stopping. My truck is now having problems stopping this thing. So I check the brake fluid and totally out. I filled it up and pulled the surge part in and out(and air bubbles were coming out). My question is

1. are the brakes on these things self purging, or how do you get the air out. I cant pump em like a car.

2. is this something your supposed to check? I dont see any signs of leaky fluid around the brakes.

HELP!

Jason

Wally

I've bleed the system just like on a car. Start at the farthest wheel from the cylinder and work your way through all the wheels till you get to the closest. If you dont have a vacume pump for the brake system you can do it with two people much the same as doing a car.
First thing you need to do is figure out where all that fluid went to begin with!! If you dont see any signs on the outside you may have to pull the wheels apart and check the wheel cylinders for leakage.

ragtop409

In fact me and a freind have used the truck to push and pull the surge cylinder. Because onece you get them close you will not be able to move it by hand.

Tinkerer

NO don't try to blead the brakes. Trailer brakes don't automaticly adjust like a car. You have to jack each tire and use a brake adjuster or large screwdriver to adjust them. Do one wheel at a time. Trailer can't be attached to car. Jack up tire and adjust tensioner while turning the wheel by hand untill you have rubbing of the pads on the drum. It should cause slight tension. Unless you are out of brake fluid any time you hear that CLUNK you are way late in doing your scheduled maintainance. BTW the adjuster is behind the rubber plug - it is the notched wheel that you will see the edge of.

Shah Mat

My dad had just finished replacing his master cylinder on his trailer and it was time to bleed them. We just blocked the trailer tires and backed his truck up gently. (BTW It worked well) All was going well and I could see the air from the bleeder screw was getting less and less each time I went to another wheel. The last one was the right front and by now the trailer and boat was moving a bit as he backed up because the brakes are starting to work. He backed up and I yelled " hold it". As I leaned over the fender, I heard this funny noise like an electric motor running and looked aroud to see what it was. Next thing I know I am drenched with water on my head and down my back.

The jerking must of stirred up some water in the foward bilge and the pump kicked on.
The drain hole could not have had any better aim.!!!!!!!!!!!

stevel

Check the cylinders inside the drums inspect the pads. The fluid went somewhere??? If no leaks are evident it is possible that the level was low to begin with and as the pads wore down, requiring more fluid in the cylinder until the resevoir was empty.

If the fluid is low or out you have to fill it up and bleed it. You can use one of the methods mentioned above with a helper or buy a vacuum bleeder and do it yourself very easily. I have a great one that works off of an Air Compressor for about $75. Small ones with hand pumps are about $25.

The adjuster wheels have to be turned until the pads just start to rub. Jack up the wheel and get under the trailer. (Be Careful)

On the backing plate the hose usually goes in at the top and there is a small access plate near the bottom. The access plate may be covered by a metal plate or rubber plug that can be easily pried out. A big screwdriver can be used to turn the star wheel or you can get a drum brake adjuster tool for a few bucks at any parts store.

Good Luck,

Steve

h2owarrior

After you get the brakes bled and adjusted you should start looking for the leak. Even if the brakes were way out of adjustment, it most likely would not drain the resivoir. I had the same thing happen to mine, clunking when pulling away after being stopped (I kept them adjusted religously), and it was leaking around the piston. Seal was shot.

When I bled my surge brakes, I used a garden tractor to compress and extend the hitch. It's a little easier for two people to communicate.

BajaRunner

Thanks for all the info. Im going to pull the tires and check around the pistons for leaks as there are not any apparent outside. I think Im going to go with the vacuum unit. Ive always used the pump em up and hold em while someone else bleeds-- in a car.

I tell you what though, big big difference when there not working, almost scary to drive.

Thanks again

JAson

GO4BROKE

I gaurentee (sp?) you have a leak in the line from the master cylinder to the first axle, inside the frame rail. I just replaced mine on a 97 trailer. Replace the line and bleed it out. Repack the wheel bearings and clean and adjust the breaks and you'll be all caught up on maintenance.

Tinkerer

First try adjusting the brakes. When my trailer was new I heard the same noise and found the reservoir dry. I added the fluid and bled the breaks. Same noise. Talked to the trailer manufacturer and then adjusted the brakes. When the brakes were adjusted properly the reservoir overflowed. The reservoir is smaller than the capacity of the four wheel cylinders. The trailer will almost lock up the tires in a panic stop.