It appears that the hollow pins are affected by the heat generated by the caliper, changing their outside diameter, making them seize in the rubber bushing.
So a quick thought would be, if the pins are removable, you could try mounting them on an engine lathe, perhaps taking a thousands off the diameter. Another thought would be if they make aftermarket pins made of a higher quality steel or a ceramic material, that is less affected by the expansion and contraction of the heat generated by the caliper. I'm sure anyway race shop dealing with your model car would have those kinds of pins. Contrary to modifying the pins, you could try finding a larger sized inside diameter rubber bushings as well. T-Mobile, America's First Nationwide 4G Network Sent by Samsung Mobile "Richard C. Wagner" <[email protected]> wrote: >Hi Gang: > >If you don't mind, I'd like to ask a question about my other car. I trust >the mechanical prowess and judgment of others on this Digest, and I'm >figuring that someone will have some good ideas for me. > >The front brake calipers on my Mitsubishi Mirage are of the floating type. >To maintain pad centering, the caliper itself floats laterally on a pair of >pins. So picture it, the caliper has a pair of bosses, inside of which >there are rubber bushings. The bushings slide over a pair of hollow pins >that get bolted to the steering knuckle. The caliper can then slide left >and right to accommodate any runnout in the rotor or wear in the pads. >Here's the problem: After a short time, the rubber bushings freeze to the >steel pins. And after that happens, the calipers no longer float. Instead, >the outboard pad gets held against the rotor and wears out prematurely. I >just lost a really nice set of Akebono ceramic pads to this issue. > >I've tried lubricating the pad/pin contact surfaces liberally. And that >works well for a short while. But eventually, the grease seems to get >absorbed by the rubber and you get the sticking problem back. I've tried >lithium grease, silicone brake grease and molybdenum grease all with the >same result. Works great for a short time. Wait too long between checks >and your great Akebono pads get munched. I think the real solution is to >have someone make a set of delrin or nylon bushings to replace the rubber >ones. But I don't have the time or resources to do that right now. > >Does anyone have any ideas on what I could try here? I'm wondering if there >might be some other lubricant that might work. And as always, thanks for >your indulgence. > > >Rich Wagner >Montrose, CO >(That will soon change to Seattle vicinity, Montrose, CO and parts >elsewhere.) >'82 GTV6 >-- >to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi >or email "unsubscribe alfa" to [email protected] -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
