brake magnet

[rrab1]

Hi all, Has anyone had a brake magnet go bad? I an getting a intermittent overload on my brake box then it will be fine for day's and when I get the overload I have no brakes. It is not my truck it will do it hooked up to another truck too. I have checked for bare wire's from the plug back to the wheel's. We are leaving for Colorado,Utha, and Las Vegas on 6-23-07 Thank's in advance Don Barr

 

[jelag]

I've had the wires that cross over in the axle tube fray on the inside of the tube and short out the brake circuit... . I also sell all the parts to the brake... . It's common if you don't adjust the brakes like you should to have them get loose and the magnet moves the arm and shoes farther than they should, which causes rapid wear and can cause the parts to come loose in the drum housing and cobble up the parts making the brake short out.....

If you tow this trailer often and haven't adjusted the brakes at least once a year I'd pull them apart and check them out..... BTW we pulled the wiring out of the axles on all our trailers... . found several of them bad... . but we tow daily..... now all the wiring is on the outside of the axle so we can see what's going on.....

Hope this helps...

 

[Rattler]

I had one of the magnets on my trailer go bad a couple years ago. I kept looking for a bad wire or something else, finally changed out a magnet and everything was fine again. Randy

 

[Hoefler]

The magnets will also wear out. I replace them with the brake shoes just to be safe.

 

[rrab1]

Thank's everyone, all four magnets are going on Monday, We have put 13,000 mi. on sence we bought this 5th wheel so I hope this work's. Don

 

[BDeMartile]

It could be a magnet related wiring rubbed through at any one of 1000 points or it could be one of those great twist and tape or wire nut connections that trailer manufacturers are so great for. As was suggested if its time for an annual inspection pull the wheels check carefully the wires on the actuating arms for any wear through. Next disconnect the magnets and check resistance on each magnet separately your owners anual should tell you what the spec is but basically it should be around 5 ohms. Next follow each wire back to the plug and insure there are no shorts and lastly soler and insulate all connections and rid yourself of poor connections. This is a time consuming procedure but in the end you will have brakes that operate every time you need them and they will operate much more smoothly.

 

[JHardwick]

The magnets will also wear out. I replace them with the brake shoes just to be safe.

This my position as well.

 

[hammersley]

I've had the wires that cross over in the axle tube fray on the inside of the tube and short out the brake circuit... . I also sell all the parts to the brake... . It's common if you don't adjust the brakes like you should to have them get loose and the magnet moves the arm and shoes farther than they should, which causes rapid wear and can cause the parts to come loose in the drum housing and cobble up the parts making the brake short out.....



If you tow this trailer often and haven't adjusted the brakes at least once a year I'd pull them apart and check them out..... BTW we pulled the wiring out of the axles on all our trailers... . found several of them bad... . but we tow daily..... now all the wiring is on the outside of the axle so we can see what's going on.....



Hope this helps...

This would be a great item for some photos to show us how you adjus these brakes as well as your solution of wires ... "outside"... . hope to see some in the future... .

 

[jelag]

Electric brakes have a star adjuster just like old fashioned brake shoes...

We sell the complete backing plate with the shoes, arm, magnet etc installed so it will not be a in issue to photograph these and post it... .

The digital image is no problem... . and I'll just have to learn how to post them...

I'll try and remember to do it tomorrow... .

BTW - I'm taking my 5er apart today to grease the bearings and will adjust the brakes at the same time.....

 

[Ragain]

I do a quick check daily while towing an electric brake equipped trailer.

Pull the break-away cable out and check each wheel with a little compass. This makes it easy to tell if each wheel magnet is getting any "juicetricity".

 

[JHardwick]

Does continuity between the brake wire and common ground suggest a shorted magnet?

 

[HBarlow]

I think the answer depends on which scale of a multimeter you are reading it with.



It should be a low resistance but not a direct short.



If you suspect one try reading across one or all of the other brake magnets with your ohmeter set on a low scale to determine if all brakes read the same or one is significantly lower resistance indicating direct short to ground.

 

[JRBurton]

Magnets will go bad on trailers, I have had a couple go bad. Replace and go on or install disc brakes on trailer, less moving parts and more reliable. Also an exhaust brake wouldn't hurt, less wear on trailer brakes.

John

 

[jelag]

Backing plate assembly

This photo shows a 12 x 2 brake... . they are made as a left side and right side... left (drivers) right (passenger)

You can see the star wheel adjuster... this complete assembly shows the star wheel but what is blocked from view is the adjuster hole behind the star wheel.

Usually if you need shows, magnet etc... its faster and less expensive to just install the complete assembly...

Well the photo didn't come in centered... . and there is a pieces of cardboard sitting under the backing plate. This example is a 4 bolt set up and there is also a 5 bolt set up (bolts required to mount to the axle)

Let me know if you have any questions... I don't have a office computer here at home but as I remember we usually carry the most common sizes which are 10 x 2 and 12 x 2... .

If you have any questions I'll come back to this next week and address them.....

I'm sorry for the delay... I totally forgot to do this and it wasn't until this thread re-appeared that I remembered I'd promised to post this...

 

[starkmr]

One of the things that can cause an overload condition (not to be confused with a 'short') is bearings going out which can put a bind on the brakes. I'm having this problem now. The bearing isn't loose yet, but is making some noise when spun backwards and is causing an overload condition on my controller. Bearings will be replaced before the next trip and the brakes will be inspected and replaced as needed.