Are these brakes working properly?

[MillWeld]

Before I describe the problem I need to give my experience with trailer brakes. I installed brakes on all wheels of my tandem (2000 lb empty) trailer. When I pull the brake-away cable the brakes engage and the truck will not pull the trailer without all 4 wheels skidding. When I am pulling the trailer the drums do not warm up. I assume this is correct operating behavior.

With this experience under my belt I installed brakes on my portable ~3000 lb sawmill. (13 wheels only 2 of them). I adjusted the brakes until they locked and then backed off on the adjuster 10 clicks as is normal. To test the brakes I pulled the cable on the brake-away kit and the brakes do not lock and the truck can pull it. I re-checked the adjustment by adjusting till the drums locked and backing off 10 clicks again but - no change. (The brake-away batteries are 2 auto batteries in parallel and are part of the sawmill and has plenty of reserve power.) In actual towing conditions the brakes apparently work because I can stop quicker and quite satisfactorily. The drums are warm after a 12 mile tow (so are the tires but that is another issue). Are these brakes working right?
Bob

 

[mikehaugen]

3000 lbs on 2 13" wheels is a lot more than 2000 on 4 wheels. I guess I couldn't say for sure, but I wouldn't expect them to lock necessarily with that much weight on them. I look at it as having a 6000lbs on a tandem axle trailer, and in that case I would not expect them to lock. If it feels right while you are pulling, then I would say it is okay. Also, with 13" wheels I would have to assume they are much smaller drums than what you have on the other trailer. With the pin pulled do you feel a good amount of resistance when trying to move it? You could also find some gravel and see if they will lock up on that.

 

[Diamondpilot]

All the law says is the brake away must hold the trailer for 15 minutes. The way we do the check is hook up to a truck but leave the wiring un plugged, pull the brake away, wait 15, put the truck in gear and it should not move at a idle.

If it were in my shop I would tighten 3 clicks and try it again. If that don't work try a few more clicks. I find many times 10 clicks back is too much.

The way we adjust is to jack it up and have a helper spin the tire in a forward direction as I adjust till just a slight drag then back off 1 to 2 clicks.

Chris

 

[Soundguy]

that's how I adjust mine.. lifted and spun.. etc.. adjust till drag, then back a hair..

 

[MillWeld]

See my comments in red.

All the law says is the brake away must hold the trailer for 15 minutes. The way we do the check is hook up to a truck but leave the wiring un plugged, pull the brake away, wait 15, put the truck in gear and it should not move at a idle.
I think the mill would pass this test.

If it were in my shop I would tighten 3 clicks and try it again. If that don't work try a few more clicks. I find many times 10 clicks back is too much.
If I tighten it more won't that just make the linings contact the drum more all the time and make the drum hotter?

Chris

 

[Diamondpilot]

See my comments in red.

Can not see any red / color.

Chris

 

[Diamondpilot]

Can not see any red / color.

Chris

You may get some more heat but you just need to adjust your controller as necessary. Heat is going to happen no matter what with brakes.

Chris

 

[MillWeld]

Chris,
My concern is that tightening the brakes will cause more friction between the linings and drum and produce more heat even before the brake pedal is applied. In other words, if the brakes are tightened the linings and drum will be rubbing more all the time. Right? or am I out to lunch?
Bob

 

[schmism]

Chris,
My concern is that tightening the brakes will cause more friction between the linings and drum and produce more heat even before the brake pedal is applied. In other words, if the brakes are tightened the linings and drum will be rubbing more all the time. Right? or am I out to lunch?
Bob

if you follow the other advise given

that's how I adjust mine.. lifted and spun.. etc.. adjust till drag, then back a hair..

then no, its unlikely that the shoes are draging on the drum all the time with the above method.

FYI its how i set my drum brakes also

 

[Diamondpilot]

Chris,
My concern is that tightening the brakes will cause more friction between the linings and drum and produce more heat even before the brake pedal is applied. In other words, if the brakes are tightened the linings and drum will be rubbing more all the time. Right? or am I out to lunch?
Bob

No, you want the brakes just a fraction of a mm before touching. This is very rarely possible with brakes because nothing is perfectly round or matching. They kind of need to wear in the first few miles.

Chris

 

[kenmac]

I'm thinking you don't have your break away wired correctly. Use a vm & check for 12v at the brakes with the cable pulled. You also should be able to hear a buzzing noise comming from the brakes (both of my trailers do) if power is being supplied to the brakes with the cable pulled

 

[Diamondpilot]

I'm thinking you don't have your break away wired correctly. Use a vm & check for 12v at the brakes with the cable pulled. You also should be able to hear a buzzing noise comming from the brakes (both of my trailers do) if power is being supplied to the brakes with the cable pulled

Your ears must be better than mine but that is what 25 years of fooling with airplanes will do. I always check mine with a screw driver. The magnets will make it stick when energized.

Chris

 

[MillWeld]

No, you want the brakes just a fraction of a mm before touching. This is very rarely possible with brakes because nothing is perfectly round or matching. They kind of need to wear in the first few miles.
Chris

OK, that makes sense to me. My trailer brakes came used with the axles and were already "broken in". The sawmill brakes were new and perhaps need a break-in period. thanks. I will re-adjust them.
Bob

 

[joshuabardwell]

Your ears must be better than mine but that is what 25 years of fooling with airplanes will do. I always check mine with a screw driver. The magnets will make it stick when energized.
Chris

A compass will also work.

 

[joshuabardwell]

No, you want the brakes just a fraction of a mm before touching. This is very rarely possible with brakes because nothing is perfectly round or matching. They kind of need to wear in the first few miles.
Chris

This is my understanding too. When the brakes are new, you want to adjust them just until they drag ever so slightly. This will cause them to wear perfectly round. After 50 miles or so, there will be no more dragging and they will be just ever so slightly from grabbing.

 

[kenmac]

Your ears must be better than mine but that is what 25 years of fooling with airplanes will do.

Chris

Owning a drag race car in my previous life really messed my ears up. I guess there not as bad as I thought except for this constant ringing.

 

[mikehaugen]

One of my trailers actually has a pretty loud buzzing from all of the brakes. Others I have heard aren't as loud, maybe that is why you can't hear them?

 

[Diamondpilot]

One of my trailers actually has a pretty loud buzzing from all of the brakes. Others I have heard aren't as loud, maybe that is why you can't hear them?

I have worked on dozens of trailers with electric brakes and never heard the buzz. I must be deaf.

Chris

 

[mikehaugen]

maybe my brakes are just old and pieces of crap?

 

[Soundguy]

if you follow the other advise given



then no, its unlikely that the shoes are draging on the drum all the time with the above method.

FYI its how i set my drum brakes also

yep.. I do my tractor drum brakes the same way as well..