Bleeding caliper question

[sunny67]

I’ve bleed many brakes in my time but not calipers with apposing pistons with a bleeder only on one side. Is there any trick to get the air out of the outer cylinder?

 

[husky drvr]

sunny67,

You might try lightly tapping the caliper with a small hammer between pedal strokes.

Works occasionally.

Hope this helps,

 

[sunalp]

That's not really necessary. They bleed the same way as any other brake caliper. There's a transfer port
that keeps them balanced.

 

[mikephillips]

What I tend to do is push the pistons all the way in, bleed, then pump the pedal until it is solid which moves the pistons back out. This minimizes the amount of air that could make it more difficult.

 

[sunny67]

Thanks. Brakes are successfully bled using all three suggestions. I don’t know if it was overkill but it worked.

 

[Gumby]

I just got my calipers back from the rebuilder. (Goldline Brakes in Port Orchard, Washington. No affiliation), and I plan to do a bench bleed first. The plan is to c-clamp the inner piston, forcing the majority of fluid to the outer piston, and limit it's travel so it doesn't pop out, then open the bleed valve, and compress the out piston to expel the air and fluid from that piston. Repeating that step until there is no air coming out of that side. The clamp the out piston, and limit the travel on the inner one, and pump it up, then bleed it down the same way, expelling all of the air from both sides. Then Limit travel on both pistons, and fill it with fluid. Attach the new flex hose, bolt it up to the spindle without the pads in place, then push in the pistons, pushing fluid from the pistons through the flex hose attached to the new brake hard lines, and back through the booster to the master cylinder. Install pads, pins and clips. DONE. Repeat for the other side. There will be NO air in the caliper at all.