Electric brake testing on old trailer

[sailorman]

I inherited a small 1973 Tag-A-Long travel trailer. It appears as though it was rigged for electric brakes. There are two wires ( cut ) coming out of each of the well drums( total of 4 wires ). How might I test to see if the brakes still function before buying needed vehicle controller and wiring system ? Could I just use a 12 volt battery on the 2 wires ( + and - ) to see if brakes engage ? I havent 't yet pulled drums to see what braking system might be there. I 'll be towing with a ford ranger XLT pickup so I 'd like to restore brake function if possible. I 'm also gonna add a weight distribution sway control hitch system if that matters.

 

[dnetherland]

I just had to check brakes on a dump trailer. If you use a 12 v battery you should be able to hear a hum when the brakes engage. To check function (ie make sure the brakes are holding) you would need to jack up that side and see if the brakes keep you from spinning.

DN

 

[dnetherland]

I just had to check brakes on a dump trailer. If you use a 12 v battery you should be able to hear a hum when the brakes engage. To check function (ie make sure the brakes are holding) you would need to jack up that side and see if the brakes keep you from spinning.

DN

 

[Craig Clayton]

What I have heard from others is they remove the electric brakes and replace them with hydraulic backer plates.

Craig Clayton

 

[sailorman]

I just had to check brakes on a dump trailer. If you use a 12 v battery you should be able to hear a hum when the brakes engage. To check function (ie make sure the brakes are holding) you would need to jack up that side and see if the brakes keep you from spinning.

DN

Thanks. I was hopin' some one would say that :thumbsup:

 

[sailorman]

What I have heard from others is they remove the electric brakes and replace them with hydraulic backer plates.

Craig Clayton

I 'm not familiar with that term. Did a google, but all I found were prices. No explanation of what they were or how they worked. Can you tell me more ? I 'm a little skeptical that something can be adapted to a 1973 brake rig or that I have the skill to do it. Thanks.

 

[Diamondpilot]

As others said 12V to the wires will engage the brakes if they work. Does not matter which wire is positive or negative. My guess is everything is rusted all up and will have to be cleaned and worked free.


Chris

 

[sailorman]

As others said 12V to the wires will engage the brakes if they work. Does not matter which wire is positive or negative. My guess is everything is rusted all up and will have to be cleaned and worked free.


Chris

Diamond, I 'm thinkin' the same thing about the rust. Just haven 't gotten around to pullin' drums for a look see. Camper has had multiple owners over the years and at some point some one just cut the wires. I think he may have used the trailer as a primitive sleeper at a huntin' camp and wasn 't gonna move it and didn 't have a vehicle compatible with brake system.

I 've completely gutted it and am slowly rebuilding interior in a spartan way just for basic creature comforts for back woods campin'. But would like to have as much road functionality as possible. Brakes are good to have. Never know when I'm gonna have to stop quick with a light tow vehicle.

 

[Diamondpilot]

They did not know what they were doing then. No reason to cut the wires to make the brakes not work. If you do not have a controller it will not work.

Chris

 

[sailorman]

Diamond, I agree on the not knowing what they were doining. At some point the running lights system was rewired and done very badly. I think they just cut any wires they didn 't like and only did the running, tail, and brake lights. I re-wired the lights before I realize brakes were present with a flat plug. If I find they work, I will then spend money on controller and all else needed.

 

[radioman]

only reason to cut wires if it was shorting out and keeps locking up brakes. In this case, all they needed to do is replace it with a new wire.

You didnt say how heavy the trailer is. I think you really need to know this esp. with a lightweight truck like yours.

 

[sailorman]

only reason to cut wires if it was shorting out and keeps locking up brakes. In this case, all they needed to do is replace it with a new wire.

You didnt say how heavy the trailer is. I think you really need to know this esp. with a lightweight truck like yours.

Not sure what the weight is 'cause I 'm renovating it. It is small. I am 5' 6" and 132 lbs and at this point I can lift the tongue off the ground. It will get a bit heavier as I complete the interior. I am using the lightest materials I can and am not adding any frills like frig, stove, heater, holding tank, water tank. If I'm reading my truck manual correctly it is rated to pull a 3940 lb trailer, but I am still pondering if my calculation is correct.

 

[brain55]

What I have heard from others is they remove the electric brakes and replace them with hydraulic backer plates.

Craig Clayton

Nobody I know has ever done that. If anything they have done the opposite. The only place for hydraulic surge brakes in my opinion is on a boat trailer. Every trailer I have worked on, it was cheaper to swap over to electric brakes than repair the hydraulic brakes and more reliable. I'm sure there will be people that disagree with me, but that is my experience.

Brian

 

[Craig Clayton]

Some years back I was given some 6000 LBS axles because they had been removed from somthing. All the electric brake magnets were burned and the entire backer plates were rusted. I was told that the haulers of this size wanted to switch to hydraulic as they were more reliable.
I worked with a gentlemen who told me a story about one day he tried to back his hydraulic brake camper trailer up his drive, it would not back up. He forgot to put in the pin that stops the brake cylinder from pushing on the brakes. So his axle was around the same time era as the posters travel trailer.
Backer plates are just bolt on to the axle flange. So all that is needed for hydraulic brakes should be the backer plates, flex line , and a run of brake line up to a master cylinder.
I have looked at but I am not sure I think there is a electric solenoid that pushes on a master cylinder to cause the brakes to apply this was a higher end quality.
Backer plates, flex lines, wheel cylinders and brake line I have changed all to keep my vehicles running.

Trailer Parts Superstore - Electric, Hydraulic & Air Trailer Brakes

This was the first google that I tripped over for trailer brakes.

Craig Clayton

 

[Diamondpilot]

Some years back I was given some 6000 LBS axles because they had been removed from somthing. All the electric brake magnets were burned and the entire backer plates were rusted. I was told that the haulers of this size wanted to switch to hydraulic as they were more reliable.
I worked with a gentlemen who told me a story about one day he tried to back his hydraulic brake camper trailer up his drive, it would not back up. He forgot to put in the pin that stops the brake cylinder from pushing on the brakes. So his axle was around the same time era as the posters travel trailer.
Backer plates are just bolt on to the axle flange. So all that is needed for hydraulic brakes should be the backer plates, flex line , and a run of brake line up to a master cylinder.
I have looked at but I am not sure I think there is a electric solenoid that pushes on a master cylinder to cause the brakes to apply this was a higher end quality.
Backer plates, flex lines, wheel cylinders and brake line I have changed all to keep my vehicles running.

Trailer Parts Superstore - Electric, Hydraulic & Air Trailer Brakes

This was the first google that I tripped over for trailer brakes.

Craig Clayton

You are talking about electric over hydraulic. I tow a couple trailers with these. They are in the 20,000# to 30,000# class. I hate them. 2 systems to maintain and very expensive. The master cylinder alone with the electric actuator is about $600 then you need a controller and the the brakes themselves.

I personally like pure surge brakes on boat trailer upto 18,000#. The one issue is there is no brakes when backing down a boat ramp and that can get interesting. My F-350 Powerstroke has no issues but it my boat that weighs 15,600# would drag my 3500 GMC Dmax backwards 5' before it stopped. These are simple and have way more stopping power than a electric brake but do have limitations. Other nice feature is most modern surge brakes are disc brakes and use Ford parts so they can be serviced with parts from any Napa, ect for a fraction of the cost. For example I used to pay $50 for shoes and now pay $10 for pads. Drums used to cost me $50 each also but now rotors can be had for about $20.

Electric brakes are the cheapest and work really well. I would say they are 85% as effective as the surge brakes I use. The down side is you must have a truck set up to use them. For most applications they are the best choice. New electric brakes with sealed components are making way on to boat trailers. The only limitation I have seen is they are for use in fresh water only.

Chris

 

[Jay4200]

I'm not sure you can just put 12V to an electric brake. Brakes take controlled current as input - usually 0-20A, not voltage. If you apply a straight 12V, you are providing virtually unlimited current - limited only by the impedance of the wire. I don't know what the effect would be.

JayC

 

[sailorman]

I 'm gettin ' a lot of good info from ya 'll. Not sure which way I 'll go. First step is to inspect brakes for condition and test for operation. My truck did not come with electrical hookup trailer brakes. It came with a factory 4 pin flat plug to run lights on trailers, but not brakes. I have the matching 4 pin harness newly installed on trailer. Gotta figure how to deal with that. All the controllers I 've seen seem to use a round plug controling trailer lights and brake system. Suggestions and how to 's are most welcome from anyone with ideas.

 

[mjw357]

At a minimun, you will need to convert to a 5-pin flat plug if you want to use electric brakes. If your state laws require a breakaway brake system for your trailer, you will want to go to a 7-pin RV style plug so you can charge the breakaway battery.

Not sure what size your brakes are on that trailer, but new assemblies (backing plate, springs, actuator etc) can be had for $40-$50 per side. You may be able to have the drums cleaned up at a brake shop.

I think it is worth the investment. Even a lightweight trailer can get out of control under certain conditions. If it starts swaying around in high winds, for example, you can apply light brakes manually to get it settled down.

 

[orezok]

I'm not sure you can just put 12V to an electric brake. Brakes take controlled current as input - usually 0-20A, not voltage. If you apply a straight 12V, you are providing virtually unlimited current - limited only by the impedance of the wire. I don't know what the effect would be.

JayC

No different than when the breakaway switch is activated. Battery direct to magnet. Each magnet will draw about 3 amps maximum.

You can also check if the magnets are still working by bringing a compass near the wheel while activated. The needle will swing toward the magnet. My hearing isn't what it used to be so I can't hear them hum.

 

[CurlyDave]

Before you go to the effort of electrical troubleshooting, jack one side up and take the wheel off so you can see what is really in there.

I agree with others--there is probably so much rust and corruption in there you will need to fix that part first. It may be better to just fit a new set of electric brakes.