Mushy brakes

[Rick Erwin]

Does anyone have any idea as to what the normal brake pressure should be when fully applying pressure to the pedals?

[YankeeClipper]

Based on some of the helpful feedback you all have been giving, my IA has decided to go ahead and replace at least one of the brake cylinders. I'm not sure this is really where I'm taking on air but they are fairly old and it's worth a shot. They were of course repacked with new bits recently, but he wonders if, as one of you have pointed out, it's not leaking out past the seals.

So in my search for this I've noticed that Cessna part numbers are different from left hand and right hand, yet the Cleveland part number for my Delta model shows only one part number: 30 - 61D. Then, confusing matters all the more for me, the Cessna part catalog doesn't really specify different brakes for different years, at least not for 65 through 71. But Cleveland does. Can I use the 30-69B that they specify for the echo models, even though mine is a delta?

[RandyArizona]

Originally Posted by YankeeClipper

So in my search for this I've noticed that Cessna part numbers are different from left hand and right hand, yet the Cleveland part number for my Delta model shows only one part number: 30 - 61D. Then, confusing matters all the more for me, the Cessna part catalog doesn't really specify different brakes for different years, at least not for 65 through 71. But Cleveland does. Can I use the 30-69B that they specify for the echo models, even though mine is a delta?

Ok, you need to slow down a little.

Do you have cleveland brakes?
Has your IA checked, and / or replaced ALL of the hoses? The big one, that is always overlooked is the short one, from the hard line to the caliper.
It has a hard outer shell, but it can leak, or suck air as it hardens, and gets old.
S2178-4-0057A Fig 46 item 23
(I think it crosses to another number)
It takes alot of abuse being where it is.

I changed out my calipers a few years back, and I think I got the 30-69B with pins, and of course the AN fittings.
The calipers are "one size", and for left or right, you just put the AN fittings on the "up or down" side. The pins are are just driven in, with a mallot and a block of wood, (measure for the depth)

As for the different numbers, (30-61D, or the 30-69B), I am going to have to do more research.
Regards,
Randy

[RandyArizona]

Cleveland has a component mx manual, AWBCMM0001
Section 101 has a troubleshooting table.

Get it here. https://www.parker.com/literature/Ai...AWBCMM0001.pdf

It is cleveland specific, but good info for all brake systems.

I am still looking for specific numbers, if you do NOT have cleveland brakes.

If you do NOT, please send your aircraft S/N so I can look it up specifically.
Regards,
Randy

[RandyArizona]

Originally Posted by Rick Erwin

Does anyone have any idea as to what the normal brake pressure should be when fully applying pressure to the pedals?

Rick,
Hope your "Peak" was good.
The normal brake pressure number is listed somewhere, on some Cessna Geeks desk......... As for what it is, I guess my answer would be, "enough to stop the plane".
I'm sure someone could figure it out, , hose length, hose ID, master cyl., diameter, and length of throw, pressure to master cyl piston.... etc. etc...
You get the point...
Have a good new year, up coming.
Regards,
Randy

[RandyArizona]

Here is the cleveland wheel and brake cross page for the early D model aircraft.
(everyone else can insert their model, and get the data.)

https://www.aircraftwheelandbrake.co...+thru+337-1193

It shows 30-61D
With exploded view, the AMM which I referenced earlier, and a Tech service guide manual.

Good luck.
Regards,
Randy

[Rick Erwin]

Hi Randy! My last 4 “peaks” have been the best out of the last 35 years! I hope you have a great New Year!

Rick

[Joes]

Rick, I’ve owned a couple of the 6 in wheel versions of the 337’s and the stopping power of these are marginal at best. Can’t comment on the larger diameter wheel option. One things for certain it’s difficult or nearly impossible to flat spot the 6 in version. Regards, Joes

[Rick Erwin]

Thank you, Joes. My G model has the larger main wheels, and the stopping power is certainly adequate. I was asking about the brake pressure as I was wanting to pressure test a swivel fitting. I put a pressure gauge inline at the left brake caliper and all I could get out of it was about 4-500 PSI. I took the swivel fitting to 1750 PSI and no leaks, so I think it should be good to go.

Rick

[Joes]

Just do a visual if there is no fluid leaking .... no pressure loss. BTW could you lock up the wheels on the larger version, not that you would want to. What is the diameter of the brake rotor and wheel on the larger version.