Lack of Brake Authority

How to keep the Cessna 170 flying and airworthy.

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MoonlightVFR
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Joined: Sun Jan 02, 2005 5:55 pm

Lack of Brake Authority

Post by MoonlightVFR »

Prior to engine start, assistant holds brake pedal pressure on Cleveland brakes (30-63) 6 " Single Cylinder, Single piston
fig 4-14. Direct observation of clamping action, release, repeat as I physically attempt to rotate wheel. Clamped tight cannot move wheel when pressure applied.

Brake hydraulic system thoroughly serviced new 0 rings, etc. Cleveland conversion from Goodyear Cross wind 40+ years ago.

Taxi test seemed OK, Must prove itself PRIOR to going airborne. Circles on wide taxi way runup area, it works.

Up down taxiway repeatedly - total approximately 2 miles. Head back to hanger.

I have to make a cautious close quarter 90 degree turn to left to get back to my hanger Bay. Left brake left turn O.K. Right brake to straighten out turn NOT O.K., oh No - feels like I'm getting 10% braking when I need 100% to immediately stop the Left turn. System is heated up, Left wing is headed for collision with side of hanger. Pull throttle, stop.

Question to our forum. What can be done to restore Brake Authority ?
gradyb, '54 B N2890C
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Bruce Fenstermacher
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Re: Lack of Brake Authority

Post by Bruce Fenstermacher »

So your right pedal soft?

Or maybe your tail wheel is locked at 90 and your right brake would never be enough to over come it? Is your tail wheel operating correctly?


If soft pedal and your sure there is no air in the system then it's the lock-o-seal in the master cylinder.
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Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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MoonlightVFR
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Re: Lack of Brake Authority

Post by MoonlightVFR »

Thank you Bruce

Tail wheel is OK , follows me every where I go.

Pedal does not feel spongy, lock O seal is new.

Now wondering about "glazed" brake disk and linings.

Regards
gradyb, '54 B N2890C
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Bruce Fenstermacher
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Re: Lack of Brake Authority

Post by Bruce Fenstermacher »

So when your tail wheel is at the 90 you got out and was able to straighten it? Or you thing it's following you every where you want to go?

Been ther done that. Why can't I steer? Da the tail wheel is jammed and won't turn.

Glazed over brakes? Find it hard to believe.

So you have good pedal pressure. Jammed wheel cylinder? Maybe.

With the cylinder hanging loose can the pedal drive it out? Be careful not to far or you will be bleeding you brakes when the puck pops out. Is the cylinder cylinder sliding freely on the pins?
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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ghostflyer
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Re: Lack of Brake Authority

Post by ghostflyer »

As Bruce said check the locating pins on the caliper . I spray dry lub on mine due to salt water contact .
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