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Any users of the hydraulic brakes have any difficulty getting the pistons into the brake body and if so how did you get them in? I just can't get the pistons in past the O rings.

Peter

Well, yes, they are a tight fit.

I got mine in by whetting both the caliper bore and the piston with brake fluid. Then force the pistons into the caliper with a twisting motion. Be careful not to damage the o-rings; this will invariably result in a leak.

Best to be prepared for a failure or two before you get the hang of it, so get yourself a small supply of spare o-rings from Sonex.

Also, take care to align the piston properly with the bore when inserting- if not you could nick the piston. A grade in the piston rim could cause scratches in the bore causing leaks.

Thx
Kai

Kai wrote:Well, yes, they are a tight fit.

I got mine in by whetting both the caliper bore and the piston with brake fluid. Then force the pistons into the caliper with a twisting motion. Be careful not to damage the o-rings; this will invariably result in a leak.

Best to be prepared for a failure or two before you get the hang of it, so get yourself a small supply of spare o-rings from Sonex.

Also, take care to align the piston properly with the bore when inserting- if not you could nick the piston. A grade in the piston rim could cause scratches in the bore causing leaks.

Thx
Kai

A new set of pistons & o rings went in just fine...thanks. Another issue I am seeing is that with the brake pucks installed (pistons and pucks in as far as they go) the pucks lock tight against the disc when the 3/4" axle nut is made up. There is still wobble meaning the nut isn't tight enough to properly seat the bearings. I wondering if the solution is to install a thin washer between the brake body and the bearing dust washer to give just a little room between the puck and the disc allowing the axle nut to tighten the assembly against the brake body and not the brake pucks?

pfhoeycfi wrote:
I wondering if the solution is to install a thin washer between the brake body and the bearing dust washer to give just a little room between the puck and the disc allowing the axle nut to tighten the assembly against the brake body and not the brake pucks?

That's correct. Shim with a thin washer or two as needed to obtain the needed clearance for the pucks.

Art,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,,,Jabiru 3300 #261