The International Cessna^® 170 Association

My right break is quite a bit easier to depress from both seats. I have equal break authority when landing but I find I do have to push on the right break more than the left. This is a new issue. Is this something I should be concerned about and look into further? I'm new to aviation maintenance and run Cleveland double puck breaks that stop 8.50s. thanks for the help!

What do you mean by “easier”…??

Do you mean Less Force is required…?? … or do you mean less pedal-travel is required…?? …or do you mean something other?

It requires very little force depress the break. The break pedal requires almost no force to depress at first and feels as though the breaking is only occurring once I completely depress the master cylinder. My thought is that I might be low on hydrologic fluid? Thanks for your response

Natedawg wrote: ↑Mon Apr 28, 2025 4:15 pm It requires very little force depress the break. The break pedal requires almost no force to depress at first and feels as though the breaking is only occurring once I completely depress the master cylinder. My thought is that I might be low on hydrologic fluid? Thanks for your response

And …are you saying that the left brake requires “extra” force before the pedal moves..?

There is very little effort required to “take up” the “slack” in pedal movement prior to actual brake (Hydraulic) pressure is created. Only after the pedal is rotated freely until it moves the master-cylinder-piston against fluid-resistance will any “effort” be required to create braking-action.

170-B IPC, Page 100, Fig 59, Item 13 is the brake master cylinder “piston return spring”. That spring returns the piston (and therefore the rudder pedal) to the neutral position.

Natedawg wrote: ↑Sun Apr 27, 2025 11:55 pm My right break is quite a bit easier to depress from both seats. I have equal break authority when landing but I find I do have to push on the right break more than the left. This is a new issue. Is this something I should be concerned about and look into further? I'm new to aviation maintenance and run Cleveland double puck breaks that stop 8.50s. thanks for the help!

If you mean the right brake pedal travels farther before it activates the brake, I recently had that identical issue. I was low on brake fluid in that master cylinder, and replaced the lock-o-seal and piston o-ring. Thinking that the left brake wasn’t too far behind, I did both master cylinders while I was at it.

You have less brake fluid (5606 hydraulic fluid) in which ever master cylinder that you must move farther to get braking action. Less fluid leaves more room for air which must be compressed before fluid is moved which will not compress. Levels don't have to be perfectly level between master cylinders but when the difference gets to the extreme ie one full and the other. Sometimes a lock-o-seal can be temperamental or worn requiring more fluid to pass through it until it seals in my experience.

Thanks for the help everyone

I had a spongy break as well, and in my experience it got worse to the point that full travel was required to crosswind taxi. I drained the fluid lines, installed new seals at the master and caliper, then pumped fresh fluid up from the caliper nipple using an oiler can. Now both are fresh and strong feeling. Don’t defer this item too long.