How to Replace Brake Caliper Seals

Replacing brake caliper seals is a skill that all motorcycle, ATV and UTV owners should know how to do. When working on brake parts, it’s important to keep everything as clean as possible. 

Even a small amount of dirt getting into the hydraulic system can quickly damage seals, brake pistons or caliper assembly walls. Have an area prepared to clean the brake caliper before disassembling it, and a separate clean area to lay all the parts out and reassemble them. Watch the video above and follow the steps below to change the piston seals in a standard brake caliper. 

Tools and Supplies - Brake Caliper Seals Replacement

• Brake caliper seals
• Contact-brake cleaner
• Brake fluid
• Compressed air gun

NOTE: The process for replacing brake caliper seals is the same or similar for any type of brake caliper, with the main difference being whether the calipers for your machine have one, two or three pistons per caliper. 

Changing Brake Caliper Seals

Step 1. Use contact/brake cleaner and a nylon brush to clean off as much dirt and grime as possible from the brake caliper assembly. 

Step 2. Place a piece of cardboard over the caliper pistons to prevent them from flying out, and squirt compressed air into the caliper through the opening where the brake hose connects.

Step 3. Remove the pistons once they’re out far enough and place them on a clean surface.

Step 4. Remove the old seals from inside the brake caliper, being careful not to scratch the inside of the caliper.

NOTE: Each piston usually has a dust seal toward the outside of the caliper, and a compression seal further down inside the caliper. On older machines, there may just be a single seal.

Step 5. Thoroughly clean the inside of the caliper with contact/brake cleaner, then give it a final clean with a paper towel soaked in brake fluid.

Step 6. Thoroughly clean each of the pistons with contact/brake cleaner and paper towels.

Step 7. Install the new piston seals into the caliper, being careful not to rip or damage the seals or scratch the inside of the caliper.

Step 8. Lightly lube the piston seals and the pistons with brake fluid, then reinstall the pistons into the caliper. Simply press down on each piston, keeping it as straight as possible until it pops down into the caliper.

Once the pistons are back in the caliper, remount the caliper to the machine, reconnect the brake hose, bleed the brakes and you’re done.