View Full Version : Any way to unstick calipers on an '03 trailer?
My '03 trailer was dipped in brackish water 2 times (and probably not rinsed after) by the previous owner, and the calipers are locked up. Is there any way, short of replacing the calipers, to unstick them, and get the brakes working again? Any guesses on the cost of 2 calipers? I can tell the calipers are stuck because the brake discs aren't getting any wear. But, there is a good bit of slack when you pull away from a stop after a firm brake. I would expect very little play with the calipers being stuck open.
08-30-2004, 11:20 AM
If they're stuck from corrosion, you'll need to remove them and rebuild them. Take the calipers off, rem the dust boot and then unstick the pistons (may require alot of wd 40). Get the rebuild kits (New dust boots and Orings), you'll need to hone out the piston bores and polish up the pistons. Reassemble and bleed the brakes.
I've never rebuilt calipers before, but it doesn't sound too bad. Can the honing and polishing be done with a dremel tool?
08-31-2004, 11:45 AM
Rebuilding them is a pretty straightforward operation. No, you can't use a dremel tool. Buy a cylinder hone from the parts store (Napa has them). They come in different sizes. Not very expensive. Get one to match the diameter of your piston bore. You can polish the piston with some fine emery cloth. 400 grit or finer.
If the rust has pitted either the piston or cylinder, they may leak, you should look at new calipers before rebuilding. If the pitting is minor, you can get away with just a rebuild though.
I checked on getting a rebuild kit today, and mastercraft doesn't make one. The calipers are $90 each. Do you just cross reference the caliper and get the parts at an autoparts store?
I checked the fluid level today, and the reservoir was dry. I think thats why there is so much movement of the hitch when I pull away from a start, so I went ahead and filled it. I plan to try and bleed the brakes and see what happens. I might even try and spray the pistons with a penetrant first.
Just to update, I went to bleed the brakes, and noticed the fluid was empty. I just assumed since the trailer was so new, that fluid level would not be an issue. Well, just filling the fluid took away the play in the tongue, and I got a little braking action back, so, luckily my calipers are unstuck. I went ahead and bled the brakes, and got a good bit of air out, and now the brakes seem to work pretty well!
My concern now, is how the fluid leaked out, or maybe the fluid was never filled all the way? The base of the reservoir looked rusty, and the fluid looked bad with a good bit of sediment in it. The left side caliper bled fine, with a good stream coming out, and the fluid went clean. But the right side was very slow to bleed, the fluid never really went clean, and it seemed most of the fluid came out around the bleed screw instead of out the nipple. I tightened it, and applied pressure, but didn't see any signs of leakage. I plan to run it as is for a while, and monitor the fluid level, and then bleed it again next summer.
Workin' 4 Toys
11-21-2005, 10:00 AM
Hmmmmmm???? I hope they never had a home rebuild kit for these...
The last times I was at MC service classes, they said the brakes are basically Chrysler import parts, so they should be easy enough to replace. No sense going through the work of designing all new parts when something that would work already exists. If there's a completely locked up caliper or trashed rotor, take the bad ones to a trailer dealer and they might even stock them. Or, google trailer brake parts suppliers and see what they have.