Too much travel in brake pedals

[RobertE]

I just had my flexible brake hoses and brake shoes replaced, as well as the master cylinders overhauled and now I’ve got way too much travel in both brake pedals.  I’m confident the system has been bled of all air so I don’t think that’s the problem.  My mechanic says it’s due to old, worn calipers and that, as the pads wear in, the problem will disappear.  The overhaul of the master cylinders was an attempt to fix the problem.  Before maintenance all was well.  Anyone have an opinion on this?  Thanks.

[Floyd]

If you pump the brakes, does the travel get less?  Do not understand how wearing the pads would make the travel less.

I would bet on air in the system.

[N201MKTurbo]

I'm not confident that they are properly blead.

They will probably get better over time, but properly bleeding them will fix your problem...

[Rwsavory]

We had the same problem after the hoses were changed. There was air in the system that needed to be bled out.  It doesn’t take much air to make the brakes soft, and they are difficult to bleed. Keep on trying.

[LANCECASPER]

1 hour ago, RobertE said:

I’m confident the system has been bled of all air so I don’t think that’s the problem.  My mechanic says it’s due to old, worn calipers and that, as the pads wear in, the problem will disappear.  The overhaul of the master cylinders was an attempt to fix the problem.  Before maintenance all was well.  Anyone have an opinion on this?  Thanks.

Did he bleed them back from the wheels to the reservoir? 

[cliffy]

Do you have copilot brakes?

[dan nephin]

I’ve had the same problem. Cylinders Redone, all ines replace, and flushed both ways.  Still too much travel. After watching the calipers, themselves, I noticed that as they applied pressure to the pads,new, that they deflected at right angles to the rotor. Suggests to me that the guide pins and bushings in the torque plates are worn. Removed the pads and tried the calipers for angular movement in the bushings and it is excessive imo. Going to replace them as soon as I get my bird back from an avionics upgrade. 

[RobertE]

55 minutes ago, LANCECASPER said:

Did he bleed them back from the wheels to the reservoir? 

Yes.

[LANCECASPER]

Both at the same time?


Sent from my iPhone using Tapatalk

[dan nephin]

I only was watching one side, but when I compared the movement to a Cessna with the same calipers the difference was glaring. I also tried block the brake lines at the hydraulic hoses,and the pedal was hard after about 1 in he travel. 

[RLCarter]

I'm with @N201MKTurbo, there is air somewhere in the system (given everything is correct).. eventually the air will migrate up past the master cylinder(s) but its quicker to just bleed them 

 

[RobertE]

I don’t know

[RobertE]

47 minutes ago, LANCECASPER said:

Both at the same time?


Sent from my iPhone using Tapatalk

I don’t know if he bled both at the same time.

[cliffy]

Again Do you have copilot brakes?

If you do its a b&^%ch to bleed them as you have to get the shuttle valve to move over so you can bleed the copilot side and then move it back again to redo the pilot side. If you don't you will never have good brakes.

[RobertE]

17 minutes ago, cliffy said:

Again Do you have copilot brakes?

If you do its a b&^%ch to bleed them as you have to get the shuttle valve to move over so you can bleed the copilot side and then move it back again to redo the pilot side. If you don't you will never have good brakes.

Sorry.  No copilot brakes (but I wish I did!)

[LANCECASPER]

2 hours ago, RobertE said:

I don’t know if he bled both at the same time.

My A&P/IA rigs up a contraption to bleed both at the same time to get the stubborn air bubbles out.

[Guest]

There has to be air in the system for the brakes to be soft.  Install a fitting in the top of the reservoir, attach a clear hose the the fitting and run it into a container.  Hook a pressure bleeder to the wheel cylinder and force fluid up to the reservoir until all bubbles  are gone.

Clarence

[FloridaMan]

They’re not fully bled. Go pump them about fitty-leven times. 

[Yetti]

That's not how hydraulic systems work.  Air in the system.

[EricJ]

Do they travel far freely and then stop at a hard pedal or do they travel and slowly build up pressure?    The former is too much travel in the system, probably due to too many stacked tolerances somewhere, or perhaps what dan naphin is describing.   The latter is air in the system.   There could also be a combination of both, but generally that's an easy way to tell them apart.

[hammdo]

I’ve used this on my race cars:

https://www.amazon.com/gp/product/B00OM751EC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

2 of these on each side and just keep filling the reservoir until no air...

Runs off compressor air but, the vacuum it pulls is wonderful for bleeding brakes...

extreme option but something to consider...

-Don