I converted my Sunline to electrohydraulic disc brakes. The trailer came with a Hayes 2500# axle, which is a really odd setup, so I decided to make a custom brake setup. This was winter 2002/2003.
The backing plate was welded to the axle flange, and the brake pivots and stops were part of the flange. Nasty old drum brakes.
So I ground off the plates and pivots, except for one pivot point, which would carry some load of the new caliper plates. Then I drilled and tapped for my new caliper plates.
Heres the back of the old drum. Looks perfect for carrying a rotor on the backside through the studs, like UPF does with their disc brakes.
I had the drums plasma cut from the hubs, and then I turned the hubs clean. Then I filled in the space from the old stud heads with 13/16" round stock held in by metal epoxy, ground smooth. Then I reamed through both for the new longer studs. The perfect studs came from a 60s Chevy work truck. The rotors, the largest diameter I could fit beneath my 14" wheels and the lowest hat height to clear the trailer frame, came from a late 80s Grand Prix.
Some grease on the studs, and some old lugnuts, and the studs pulled right into place and the assemblies fit nicely. At this time I also installed new bearings and races and seals. I had to mix and match parts to get what I needed, but all the bearing parts are available.
Here is the first plate. Grade 8 bolts hold everything.
Here is the 2nd plate. Between the grade 8 bolts, and the way the plate is nested tight against the axle flange, the plate is not going anywhere.
A dry fit of the hub and rotor proves good engineering. The counterbored bolts in the first plate just clear the back of the hub as planned.
A dry fit of the caliper. Everything lines up. The calipers are from a Pontiac 6000.
Fast forward a few years, through a divorce, and other issues, and waiting for a good deal on a Hydrastar, and I finally finished the brakes this summer 2006. The hoses and brackets are from an Astro van. Everything fits perfectly.
A shot of the disc brakes beneath the wheels.
I got my Hydrastar on Ebay for $128, normally a $500-$800 item. Used, but it works great, and wiring it wasnt hard to do. I plumbed and bled the lines, and the brakes work excellent, much better than the old electric drums. I took it for a few test drives. These brakes practically stop the rig on a dime.
We are taking the Sunline out in late September 2006 for a week long trip. First time itll have been used by me outside of the driveway.
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