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I cannot seem to get a "brake".
Posted by: Kristi ()
Date: June 26, 2022 04:13PM

Hey all.

I want to get your expertise on an issue that I am having with my '64 Monza 110 convertible. I knew it was time to re-do the brakes because I had ripped a brake hose in transit. These brakes has not been touched since probably 1987 or 88. When I tore them apart, I found that the passenger front brake was an early model, pre 1964 non self adjusting brake. The front drivers brake had the wrong hardware on it. So I set to work....
Now that I have replaced shoes, hardware, hoses, lines, rebuilt wheel cylinders, replaced the incorrect drum and backing plate to a '64, installed a new master cylinder, I have bled it 4 times with a partner. The brake pedal feels good until I start the car and put it in drive. I then have little if any brakes. Goes all the way to the floor and I get hardly any braking action.

This has happened for the past 4 brake bleeds. Please give me your opinion on what is happening. How come I have no brakes?!

Kristi

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Re: I cannot seem to get a "brake".
Posted by: Colorsarge ()
Date: June 26, 2022 04:23PM

Did you bench bleed the master before installation? Is it the original single type or did you switch to a dual master?

Frankford, De., eight miles north of Ocean City, Md.
1966 Corsa convt.

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Re: I cannot seem to get a "brake".
Posted by: Kristi ()
Date: June 26, 2022 05:26PM

Bled and original single.
Kristi

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Re: I cannot seem to get a "brake".
Posted by: Frank DuVal ()
Date: June 26, 2022 05:37PM

What is your bleeding procedure? Step by step, you can say next wheel cylinder the same to save typing.

Frank DuVal

Fredericksburg, VA

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Re: I cannot seem to get a "brake".
Posted by: ihscomputers ()
Date: June 26, 2022 06:00PM

Have you properly adjusted the shoes before bleeding the brakes?

Here's a video by Larry Claypool who shows how to adjust the shoes starting at about the 34 minute mark

Larry Claypool shows how to properly adjust brake shoes

Dean F. Gemberling
Columbus, Georgia
Heart of Georgia Corvair Club Webmaster
Springfest Webmaster

1963 Rampside w/305 V8 - Built by Ken Arnold in 1998

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Re: I cannot seem to get a "brake".
Posted by: junkman ()
Date: June 26, 2022 06:46PM

Did you check the master cylinder push rod for a proper fit? Also, check for a rusted-out line in the tunnel area. When I did mine back in 1990, I rebuilt all the cylinders including the master, installed new lines where necessary, and filled it with silicone brake fluid. Haven't had to do anything to them ever since. If you have too much clearance between the shoes and the drum, no brakes. Too much clearance between the master cylinder push rod and the piston, no brakes. Improperly rebuilt cylinders, no brakes. You are just not going to catch a break by typing, if you don't first do the searching. smiling smiley

---------------------------------------------------------------------------------------------------------------
Woodstock CT... Located on the Connecticut / Massachusetts border, approximately 6 miles from the center of Southbridge MA. About 45 minutes from Hartford CT. 1 1/2 hours West of Boston MA. Woodstock CT to Los Angeles CA 2,937.1 miles. 1 Mile as the crow flies to Big Bird's nest.

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Re: I cannot seem to get a "brake".
Posted by: Kristi ()
Date: June 26, 2022 07:07PM

Ok. I thought I had the correct clearance/ bleeding procedure- driver rear, passenger rear, passenger front, driver front...pump up several times, hold until bleeder is released, to the floor, tighten bleeder, then pump up and repeat at least 2 other times.

I will check the clearance in the morning.

Do you still need to manually adjust 64 self adjusting brakes?

Thought I could fo the back up while applying the brake/ forward while applying the brake method in the manual.

Kristi

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Re: I cannot seem to get a "brake".
Posted by: MattNall ()
Date: June 26, 2022 07:50PM

Put the car on stands. Parking brake OFF!!

Rotate wheels to hopefully feel some "drag"

If not... Pull drum and adjust.

MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
...............110-PG.................................................Webered-Turbo

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Re: I cannot seem to get a "brake".
Posted by: wittsend ()
Date: June 26, 2022 09:07PM

Kristi Wrote:
-------------------------------------------------------
>
> Do you still need to manually adjust 64 self adjusting brakes?

>
> Kristi


I general, yes. The "self adjusting" aspect comes into play to keep the brakes properly adjust AFTER they have been initially set upon install.

------------------------------------------------------------------------------

***'61 Lakewood, a "Freebie" in hibernation for 27 years - In the process of applying CPR.***

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Re: I cannot seem to get a "brake".
Posted by: vairmech ()
Date: June 27, 2022 03:55AM

wittsend Wrote:
-------------------------------------------------------
> Kristi Wrote:
> -------------------------------------------------------
> >
> > Do you still need to manually adjust 64 self adjusting brakes?
>
> >
> > Kristi
>
>
> I general, yes. The "self adjusting" aspect comes into play to keep the brakes properly adjust AFTER they have been initially set upon install.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Put a second yes to that!

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: I cannot seem to get a "brake".
Posted by: JimBrandberg ()
Date: June 27, 2022 04:36AM

I'm a little puzzled. It sounds like you have a good pedal but then it goes away.
If I were you I would manually adjust the brakes first. The stroke of the wheel cylinder travel can only do so much and the entire travel may not even be getting the shoes out against the drum. With EM I like to jack the rear suspension up somewhat when adjusting the brake rather than doing it at full droop.
Then I would bleed the brakes yet again, brake fluid is cheap. I use a clear plastic tube into a pop bottle so I can watch for air bubbles. You might get air bubbles the first time or two and then they usually subside.
If the system has been empty it's sometimes difficult to get the air out. A big air bubble tends to just go back and forth. Once you get one wheel successfully full of fluid it gets easier.
Some people say it isn't necessary but I have a lot less trouble getting things going if I bench bleed the master cylinder. That's done with the MC in a vise and a short steel tube with a tube nut going back into the reservoir. Pump with a screwdriver or something inserted in the plunger until the bubbles stop.
Another method to get things going through the chassis is gravity bleed. Open a bleeder into a hose into a bottle and then go do something else for a while. Return occasionally to check the level. Once it starts to flow you don't want the MC to go empty and have to start all over again. Sometimes this method works for me and sometimes not. I always follow this up with regular bleeding.
Since getting full lines in part of the system helps get the others going, sometimes it's good to get the fronts going since they're easier. Then bleed the rears, then bleed the fronts again.
Sometimes it's really frustrating so just hang in there.
Sometimes after all that the MC is bad but not usually.
If after all that you get a good pedal and it goes away you may have air getting back into the system but usually that is evidenced by fluid getting out, especially under pressure. When you think you are done you should be able to press on the pedal as hard as you can with no pedal creep.
Sorry about writing a whole novel or short story, I can't seem to help myself.

Jim Brandberg
Isanti, MN
CorvairRepair.com



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Re: I cannot seem to get a "brake".
Posted by: Kristi ()
Date: June 27, 2022 04:51AM

Novels are good! Especially when I am fighting a car that doesn't seem to want to live!

As far as the master cylinder, I rebuilt the first one so we thought it was my "skills" or lack thereof, and bought a new master cylinder. After bench bleeding, we installed and bled.

You are right in saying that I had good pedal. I did! At the end of each bleed session...good pedal! As soon as I crank the car and put it in gear...no pedal or brakes!

The lines are all good (new) even in the tunnel. No leaks anywhere. I am going to try adjusting and see if I can get some pedal from that.

Thank you for the information.

Kristi

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Re: I cannot seem to get a "brake".
Posted by: roger65180 ()
Date: June 27, 2022 05:10AM

I recently had a car in that the owner should have sued the shop that did her brakes, the only thing they did right was install new brakes hardware and drums, the shoes were not adjusted up, new rubber hose lines for the back wheels but did not install any of the hose retainer clips non of the steel lines were tight enough , all of them leaked . I replaced the front hoses and the lines above the fuel tank and did the dual master conversion. that shop also put a new gas tank in for her , they cut the dog bone sway bar link to remove the tank used 1/4 20 bolts in 2 of the clamps , used 5/16 bolts for the other 2 but both were two long, and used 3/8 rubber fuel line on the 5/16 steel lines and then used heater hose clamps on them . I am sure I am forgetting more , this was a 65 corsa turbo vert. On this car I tried a new to me way of bleeding the brakes and I did it alone. Fill the master , then install a long hose on the bleeder and make sure it is submerged in the brake fluid bottle , I started at the back and worked forward , no mess and so much faster

Roger R
Madison Wi
62 ct pg turbo
65intercooled 180 4sp,autocrosser
62 Rampy

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Re: I cannot seem to get a "brake".
Posted by: Frank DuVal ()
Date: June 27, 2022 08:48PM

Quote
Kristi
then pump up and repeat at least 2 other times.

Pump up, are you doing this slowly or rapidly? Two times will not be enough on an empty system. The pop bottle idea works well for seeing if the air bubbles are actually gone.

Quote

good pedal! As soon as I crank the car and put it in gear...no pedal or brakes!

Do you have a power brake booster (this was never a Chevrolet option but there has been at least one picture of one on the internet in the last few years an owner added because of some medical condition)? The typical Corvair is "manual" brakes in that there should be NO difference pressing on the pedal with or without the engine running. When you say you have good pedal, can you do the Hard Harder test?

A Hard Harder test is sitting in the driveway press as hard as possible on the brake pedal, then stand on the pedal, pulling up on the steering wheel if necessary. The pedal should not go further to the floor. If it does, check for the problem, as a proper brake system can take this test, after all, you want them to work in a panic stop situation, right?winking smiley

Jim's ideas are spot on. I usually just leave the bleeders open and walk away, no hoses attached. The big puddles on the floor mean fluid has gone through the system......grinning smiley This does not work on FCs, as the master cylinder is as low as the wheel cylinders.

Frank DuVal

Fredericksburg, VA

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Re: I cannot seem to get a "brake".
Posted by: Kristi ()
Date: June 28, 2022 05:12PM

Thank you, Frank. We (my husband and i)usually bleed drum brakes together on all our vehicles. I am the pedal manager and he manages the bleeders...we usually do about 3 rounds because we have bled these lines about 5 different times now. The first time after the system went back together and after we changed the master cylinder, we bled them about 7 or 8 times per wheel because of frustration. At the end of the bleeding, I have awesome pedal! Then I crank it, put it in reverse, and BOOM! No pedal...all the way to the floor. It grabs just a little at the floor but not enough to be safe even at a crawl.

You are right, it does act like a brake booster, but I assure you. This is now all 1964 Corvair technology.

Kristi

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Re: I cannot seem to get a "brake".
Posted by: irfgt ()
Date: June 28, 2022 05:19PM

Your problem is that the brake shoes are not adjusted properly. There is a procedure in the Service manual that describes the procedure accurately.

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Re: I cannot seem to get a "brake".
Posted by: jjohnsonjo ()
Date: June 28, 2022 05:27PM

Any chance you had the parking brake engaged when you did the bleeding and then released it to drive?

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa


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Re: I cannot seem to get a "brake".
Posted by: JimBrandberg ()
Date: June 29, 2022 05:05AM

I'm grasping at straws here but I wonder if you adjusted the rears at full droop. With EM suspension at full droop you can sometimes feel drag when adjusting sooner than you can when the suspension is jacked up closer to ride height.

You say you have some pedal when you're ready to go. Is there enough to do some stops in Reverse to get the self-adjusters doing their job?
It's not a good idea to bottom out the master cylinder travel.

Speaking of master cylinder travel, someone else above mentioned the push rod adjustment. You need a little free play. If the master cylinder doesn't return all the way to the top the little ports that fill it from the reservoir might not be able to do their job.
If you continue to have trouble you might want to pull the rubber boot back and verify that the piston in the master cylinder is returning to the top.

Jim Brandberg
Isanti, MN
CorvairRepair.com



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