91 240SX (no ABS) - Brake caliper pin stuck

[HachiRoku]

I was replacing my pads and rotors last week and while I was removing the caliper pins for cleaning and greasing, the upper pin on the front calipers mounts were stuck. I was able to spin the pins, but I could not pull or push them in or out of the socket.

I asked a friend about them and he says some cars have brakes where the pin is designed to stay in place but is free to spin for quick brake pad jobs, but I find it hard to believe the S13 would have that kind of design because the calipers would squeeze the pads down when I bolted the calipers back onto the housing.

Assuming this is not normal, is there anyway I can remove the stuck pins so that I can clean and grease them? I bought new boots for the pins but didn't install them because I couldn't access the pins.
Modified by HachiRoku at 12:48 AM 10/10/2006

[rogoman]

Remove the caliper mount and clamp it in a vise, then procede to remove the pin with large vise-grips.

The pins are designed to slide in and out during brake actuation.

[Q45tech]

What happens when you use the wrong lubricant or don't change pads and clean system frequently.

[NISTECH]

one of the pins has a rubber sleave on it. As Dennis [Q45tech] said , if you use brake clean or some other harsh solvent on that rubber peice it swells and becomes lodged in the bore. If you can get a new rubber sleeve or complete pin go that route as you will not be able to properly slide it back in with the old torn up sleeve.

[HachiRoku]

I got around to working on those pins today and got them free. The combination of old hardened grease and old rubber sleeves/bushings seized the pins and held them from any movement.

The first pin I worked on, I was able to free with some penetrating lube and leveraging of the pin against the edge of a table to pull it out.

I spent a lot of time with penetrant on the other pin but it was too stubborn to let go, so I decided to heat it with a torch in an attempt to soften the hardened grease and rubber sleeve so that it would let go. That worked out better than I thought it would have and I was able to quickly get that pin out.

The pins seemed fine, so I just replaced all the bushings.

Thanks for the tips.
Modified by HachiRoku at 7:04 PM 10/12/2006