1959 Spongy Brakes

[PaulB]

This weekend I replaced the master cylinder, adjusted brakes and bled the brakes. At least I bled the back wheels. Lots of air came out of the first wheel. Hardly any from the second wheel which tells me I got most of the air out of the lines. I did not bleed the front wheels because I could not get a wrench on the bleeder valve. I tried flared nut wrenches as well as standard open-end wrenches with no luck. An odd place to put the bleeder valve so close to suspension parts.
Anyway, the pedal was spongy and went almost to the floor when I started. After doing all this I saw no improvement. Without taking the wheels off there is no evidence of leaking wheel cylinders and no leaks coming from the master cylinder. I think the only thing left is the power brake booster, but that's under the dash and I don't want to take on that major job unless I know for sure that is the only thing left that it can be. So that's my first question.
The second question is; is it not uncommon for the brake pedal to travel four to six inches or so before engaging? It doesn't go to the floor, I have maybe two inches or so before I'd hit the floorboard. And the brakes stop the car but not suddenly or abruptly. It's more of a slowdown. I was thinking we're all so use to disc brakes these days that maybe I've forgotten that's the way it is with drum brakes. Any advice or suggestions would be most welcome.

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[jack-in-sac]

By the way; did you bench bleed the master cylinder before installation?

 

[Frankie the Fink]

If you didn't bleed all 4 wheels after replacing a master cylinder its not IF you have air trapped in the system its HOW MUCH is trapped. Maybe a bleeder wrench will help but you have to bleed all four wheels once air is introduced into the front of the system:

https://www.oreillyauto.com/detail/c/performance-tool/tools---equipment/mechanics-tools/brake-tools/brake-bleeder-tools/058eaccfa9b5/performance-tool-bleeder-wrench/pfm0/w80617?pos=2

Start with the proper bleeding before you go all "medieval" on the booster and shooting the car with the "parts cannon"...

 

[PaulB]

By the way; did you bench bleed the master cylinder before installation?

I did not bench bleed it if that's what you mean. After installation and filling it with fluid I started at the passenger rear wheel. I was using a vacuum pump to bleed and i filled two containers with old brake fluid before the bubbles stopped showing up in the tubes. When i went to the driver rear wheel there were very few bubbles and i filled just half the container before i had no bubbles.

 

[PaulB]

If you didn't bleed all 4 wheels after replacing a master cylinder its not IF you have air trapped in the system its HOW MUCH is trapped. Maybe a bleeder wrench will help but you have to bleed all four wheels once air is introduced into the front of the system:

https://www.oreillyauto.com/detail/c/performance-tool/tools---equipment/mechanics-tools/brake-tools/brake-bleeder-tools/058eaccfa9b5/performance-tool-bleeder-wrench/pfm0/w80617?pos=2

Start with the proper bleeding before you go all "medieval" on the booster and shooting the car with the "parts cannon"...

Thanks for the picture of the bleeder wrench. I'll buy one and try that. I know i probably have some air in the lines especially the front wheels. And i need to somehow bleed those front wheels. But i guess why i asked is i expected to see some improvement even if it was not perfect yet. Maybe less brake pedal travel or a little more firmness in the pedal. but the improvement was zero. Thanks I'll keep at it.

 

[Frankie the Fink]

They will remain spongy until all the air is removed.....air is "soft" (even a little bit) DOT3 brake fluid is "hard"...and doesn't compress.

Bleed wheel farthest from master cylinder first then the next distant and so on, never let the master cylinder run dry of fluid during the procedure.

 

[4VE]

If you want to do it right, replace the drum and cylinder system with a 4 wheel set of rotors and calipers. Toss the booster, it is no longer necessary with disks. You will be safer and much happier. Check into the system made by Wilwood. Here is the number for the 55: Wilwood M Cyl & Proportioning Block 261-13626-P

 

[Frankie the Fink]

I've done many drum-to-disk conversions and its a personal choice not necessarily "right" (or wrong) and you still have to bleed them correctly.

The all original drum brakes in my 63 Corvette saved my life - but you have to know how to maintain them and spot issues early.

 

[PaulB]

Thanks for all your advice and tips. I'm going to try the bleeder wrench Frankie mentioned to see if that fits on the bleeder valve better. And re-bleed the brakes. I'm not really interested in converting from drum to disc. I've got nothing against disc brakes, it's just an expense and job I don't think is necessary if i can get rid of the spongy brake. After all its not a daily driver. Thanks again everyone. You've been a big help.

 

[Kalla.Ivy]

This weekend I replaced the master cylinder, adjusted brakes and bled the brakes. At least I bled the back wheels. Lots of air came out of the first wheel. Hardly any from the second wheel which tells me I got most of the air out of the lines. I did not bleed the front wheels because I could not get a wrench on the bleeder valve. I tried flared nut wrenches as well as standard open-end wrenches with no luck. An odd place to put the bleeder valve so close to suspension parts.
Anyway, the pedal was spongy and went almost to the floor when I started. After doing all this I saw no improvement. Without taking the wheels off there is no evidence of leaking wheel cylinders and no leaks coming from the master cylinder. I think the only thing left is the power brake booster, but that's under the dash and I don't want to take on that major job unless I know for sure that is the only thing left that it can be. So that's my first question.
The second question is; is it not uncommon for the brake pedal to travel four to six inches or so before engaging? It doesn't go to the floor, I have maybe two inches or so before I'd hit the floorboard. And the brakes stop the car but not suddenly or abruptly. It's more of a slowdown. I was thinking we're all so use to disc brakes these days that maybe I've forgotten that's the way it is with drum brakes. Any advice or suggestions would be most welcome.

I have a 1959 as well and am currently having the same exact problem and found my front left wheel cylinder is bad. Does anyone have any idea how to get my old brake cylinder out? It’s pretty tight in there.

 

[Frankie the Fink]

Most of my work is on Chevys but generally you disassemble the brake components, removing shoes and the rubber brake line to the cylinder. Then there is a large (quite large) nut that secures the wheel cylinder; it takes a large socket (preferably a 6-point) or wrench and quite a bit of "hind end" to get it loose....may want to soak the nut in PB-Blaster overnight first. Others will correct me if I have this wrong. Also, I recommend replacing BOTH wheel cylinders on the same axle at the same time... Its only a few dollars and a little effort to do so.

 

[1rmisner]

This weekend I replaced the master cylinder, adjusted brakes and bled the brakes. At least I bled the back wheels. Lots of air came out of the first wheel. Hardly any from the second wheel which tells me I got most of the air out of the lines. I did not bleed the front wheels because I could not get a wrench on the bleeder valve. I tried flared nut wrenches as well as standard open-end wrenches with no luck. An odd place to put the bleeder valve so close to suspension parts.
Anyway, the pedal was spongy and went almost to the floor when I started. After doing all this I saw no improvement. Without taking the wheels off there is no evidence of leaking wheel cylinders and no leaks coming from the master cylinder. I think the only thing left is the power brake booster, but that's under the dash and I don't want to take on that major job unless I know for sure that is the only thing left that it can be. So that's my first question.
The second question is; is it not uncommon for the brake pedal to travel four to six inches or so before engaging? It doesn't go to the floor, I have maybe two inches or so before I'd hit the floorboard. And the brakes stop the car but not suddenly or abruptly. It's more of a slowdown. I was thinking we're all so use to disc brakes these days that maybe I've forgotten that's the way it is with drum brakes. Any advice or suggestions would be most welcome.

sounds just like what I went through on the 64 bird. First: replace all the soft line from wheel cylinders to brake lines. I found out when they are old, the soft line can swell up like a ballon and you dont get true pressures to the wheel cylinders.# 2: adjust the rod from booster into the master cylinder. Thats easy enough. U tube if U can. #3 Replace all wheel cylinders. brake fluid collects moisture over tine and I bet the wheel cylinders are a rusted mess, mine where. purge all old fluid out of the system and start fresh. I bet I took 30 times trying to get mine adjusted on the lift and it turned out to be the soft lines. Night and day. Now they work. brake shoes are cheap and easy to install. Fresh is good.

 

[1rmisner]

sounds just like what I went through on the 64 bird. First: replace all the soft line from wheel cylinders to brake lines. I found out when they are old, the soft line can swell up like a ballon and you dont get true pressures to the wheel cylinders.# 2: adjust the rod from booster into the master cylinder. Thats easy enough. U tube if U can. #3 Replace all wheel cylinders. brake fluid collects moisture over tine and I bet the wheel cylinders are a rusted mess, mine where. purge all old fluid out of the system and start fresh. I bet I took 30 times trying to get mine adjusted on the lift and it turned out to be the soft lines. Night and day. Now they work. brake shoes are cheap and easy to install. Fresh is good.

also i ground the nipples off the front ones as to leave enough to get a socket on them.

 

[jneuenburg]

I only pressure bleed. Regarding putting wrenches on bleeder nipples, here is a tip. The automotive chemical company BG Products sells professional brake fluid exchange machines. Many years ago when I was a BG rep, the machine was the PF7. They have a newer one now, I don't know the P/N. In the included PF7 adaptor kit PF9000C (new version is E100-2475) were seven bleeder adaptors to fit fractional and metric bleeder nipples. The other end is a round hole into which you put a silicone hose that came with the machine. It fits tight enough so it will not fall out when bleeding. On my personal vehicles I had a short piece of that hose going into a mayonnaise jar so I could get a good look at the old fluid. The adaptor offered two benefits. It provided a larger, more wrench-friendly hex. Good if the nipples are rounded or very tight. And the silicone hose they use is semi-clear so you can see bubbles or a color change if it is old and greenish brown. It is not likely to pop off like when putting a hose directly on a small nipple.

Below is a picture of the BG adaptors plus the Completer Kit that includes them and the hose. Probably the new kit is the same as the old one. Just find a service shop that offers the BG service using either machine and ask them to order the individual adaptor for you to fit your vehicle, or the whole Completer Kit if necessary. Ask to see their hose so you can measure it. Or buy the hose P/N you see on the drawing. They might also sell you a container of the fluid test strips they might get from BG. Dip in the DOT 3 or 4 fluid and if the color changes it is time to do a fluid exchange. You can find shops and car dealers that offer BG services and chemicals at www.bgfindashop.com

 

[1rmisner]

This weekend I replaced the master cylinder, adjusted brakes and bled the brakes. At least I bled the back wheels. Lots of air came out of the first wheel. Hardly any from the second wheel which tells me I got most of the air out of the lines. I did not bleed the front wheels because I could not get a wrench on the bleeder valve. I tried flared nut wrenches as well as standard open-end wrenches with no luck. An odd place to put the bleeder valve so close to suspension parts.
Anyway, the pedal was spongy and went almost to the floor when I started. After doing all this I saw no improvement. Without taking the wheels off there is no evidence of leaking wheel cylinders and no leaks coming from the master cylinder. I think the only thing left is the power brake booster, but that's under the dash and I don't want to take on that major job unless I know for sure that is the only thing left that it can be. So that's my first question.
The second question is; is it not uncommon for the brake pedal to travel four to six inches or so before engaging? It doesn't go to the floor, I have maybe two inches or so before I'd hit the floorboard. And the brakes stop the car but not suddenly or abruptly. It's more of a slowdown. I was thinking we're all so use to disc brakes these days that maybe I've forgotten that's the way it is with drum brakes. Any advice or suggestions would be most welcome.

replace all soft lines to "A" arms and the one over the read diff. If they are old then they swell up in side like a ballon and you dont get the pressure evenly to wheel cylinders. I spent days trying to figure mine out and the parts guy suggested I replace the soft lines and what do ya know, it workd

 

[MorrisonAF]

Be weary!! Sometimes those brake lines will clog up full of rust and crap… happened to me rear passenger drum brake line was completely clogged up!! Just a suggestion to keep in the back of your head!!