HELP - Electric Brake Problems
I have a 1970 Airstream, single axle. I just put new loaded backing plate assemblies on. The drums looked good so I installed new bearings and put everything back together.
As I was adjusting the brakes today I noticed on the lefthand side that the wheel would grab a bit when turning it backwards, sometimes to the point of jamming. Forward, no problem.
I had to move the trailer 250km today, so I hooked everything up and made the trip. The brakes got progressively better throughout the trip as they bedded in, and I was able to get the controller set for nice smooth braking. I was really happy.
So when I got home I had to back into my long, narrow driveway. As soon as I started reversing the left side wheel started to lock up (even without touching the brakes). I disconnected the wiring for good measure and it didn't matter. So it would lock up pretty good in reverse, but release if I pulled the trailer forward.
Somehow I got it into the driveway. I jacked it up, took the drum off, and everything seems normal inside. I don't see anything that could be causing it to jam. I adjusted again and tried to find the problem, but no luck. With the shoes adjusted tight and backed off slightly the wheel turns forward no problem. Turn the wheel backwards a few full revolutions and boom - locked up tighter than a drum!
This is a correct left-side backing plate, magnet and leading shoe installed as per all the images I can find online, exactly as it came out of the box.
Tomorrow I'm going to take it apart again in the daylight and see what I can find. I'm wondering if there is any rust left in the drum that catches the shoe and causes it to bind...
So, what's going on? Any ideas?