Should a Trailer Brake Magnet Make Contact with a Drum Even With No Brakes Applied
Question:
The brakes work great, but the springs for the magnets hold them against the inside of the drum slightly, just enough so I can hear it, even when the brakes are NOT applied. Is this normal, or should there be an air gap?
asked by: Dan R
Expert Reply:
The magnet should only make contact with the inside of the brake drum when power is applied to the magnet. If it is making contact with the drum all the time, you may have residual power running on the brake wire that is just enough to cause the magnet to grab the drum.
You will need to check the magnet power wire with a circuit tester, # PTW2993, to see if there is any power when the brakes are not applied. If there is, there is a short circuit somewhere and you will need to track it down. Look for loose or broken connections and wires with nicks in them. Also check to make sure the ground wires are attached to a clean metal surface both from the magnets and on the trailer and vehicle side connectors.
Also check for any dirt or corrosion on the inside and outside of the trailer connectors on both the vehicle and trailer side connectors.
You will also want to pull the hub and check for any grooves cut into the drum and wear on the magnet. If the magnet is worn it will need to be replaced. If you see or feel grooves on the inside of the drum it will need to be replaced. I have included an FAQ article that might help with further testing the magnet.
Products Referenced in This Question
Product Page this Question was Asked From
Dexter Electric Trailer Brake Assembly - 10" - Right Hand - 3,500 lbs
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- RH
- 3500 lbs
- Brake Assembly
- Manual Adjust
- 10 x 2-1/4 Inch Drum
- Dexter
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John B.
5/17/2020
Why do the little metal clips that hold the magnet in place keep breaking. Every time I pull a drum the metal clips are missing. As you know this will cause the magnet to constantly rub the drum.