How to change leaking master brake cylinder and front fuel lines

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65CherryMonza
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How to change leaking master brake cylinder and front fuel lines

Post by 65CherryMonza »

65 Monza 110

Discovered yesterday that my brake pedal dropped to the floor checked the Reservoir and it was empty... Looked at my pedal assembly and saw that cylinder is leaking under my carpet...

Found the replacement on Clark's Corvair but not sure what else I need there is the new reservoir and all the hardware. See picture.
Is some more stuff I will be needing?

As always any advise would be appreciated !
Thanks
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bbodie52
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Re: How to change leaking master brake cylinder.

Post by bbodie52 »

:think: :idea: Although the cost is greater and there is somewhat more work involved, you might consider upgrading to a dual master cylinder, which became standard in 1967 Corvairs and mandated for all new cars by law. Since you must spend some time and money for the repair, and your replacement master cylinder will likely last for many years, the added safety of the now standard (since 1967 in all cars) dual master cylinder might be considered to be a worthwhile effort, and your failed single master cylinder offers that opportunity.

Image
Image
Single vs. Dual Reservoir Master Cylinders

:link: https://techtalk.mpbrakes.com/master-cy ... -cylinders

ImageImage

Since your car is fitted with the original-style single master cylinder, you should consider an upgrade to a dual master cylinder. Also be sure to inspect the parking brake cables and pulleys, and replace any components that show signs of wear.

:link: http://www.corvair.com/user-cgi/catalog ... w_page=145

:link: http://www.corvair.com/user-cgi/catalog ... w_page=148

Also, if you find evidence of rust and corrosion in your failed master cylinder, you should inspect the bore of each wheel cylinder. If they show signs of rust or corrosion, similar decay may be present inside the aging steel brake lines. Installation of a dual master cylinder will help somewhat if a steel brake line ever bursts from internal water damage. The brake fluid should also be flushed and replaced, since brake fluid is hygroscopic and the aging fluid in those brake lines probably has a high percentage of water in them. The water content can cause corrosion inside of the steel lines, decay in the flexible brake hoses, rust and corrosion damage in the wheel and master cylinders, etc.

There are many ways for moisture to enter your brake system. Condensation from regular use, washing the vehicle and humidity are the most common, with little hope of prevention. Glycol based DOT 3 & 4 fluids are hygroscopic; they absorb brake system moisture, and over time the boiling point is gradually reduced. Clark's recommends flushing and replacing the brake fluid every 2-3 years to reduce water contamination.

Image

:link: http://www.corvair.com/user-cgi/catalog ... w_page=145

Dual Master Cylinder Kits – 62-66 Cars

Part number C10077: DUAL MASTER CYLINDER KIT-65-66 PROB!!!-WILL NOT FIT CARS WITH A/C

Weight: 10 lbs 0 oz
Catalog Page(s): 145
Price: $ 165.65


Image

Be sure to check the parking brake cables and pulleys. These are particularly important on a Powerglide automatic transmission-based Corvair, since the Corvair automatic lacks a PARK position to lock the transmission. Because of that the Corvair relies heavily on the parking brake system, which is the only thing that prevents your Corvair from rolling away on a hill! If a plastic pulley cracks or a cable snaps (usually without warning) your car can decide to take an unaccompanied trip without your permission.

:link: https://ssl.corvair.com/user-cgi/catalo ... w_page=148

Corvair Center Title Bar.jpg
Dual master cylinder conversion
:link: http://corvaircenter.com/phorum/read.php?1,485280

52bagman wrote: Date: February 20, 2012 04:47PM

My way is to get dual master from flaps, the lines from a 67 and up car and the brass block on the fire wall under the dash. Pics are from a 66 sedan that I switched recently.

Sam C. Saunders,Pt. Pleasant WV
68 500 cp 95 pg ash gold
66 Monza cp 110 4spd black
68 500 cp 95 3spd blue "DAIRY QUEEN CAR"
1966 Corvair Dual Master Cylinder Conversion
1966 Corvair Dual Master Cylinder Conversion

Roger Parent offers some improved components (throttle linkage, pulleys, etc.) that are designed to last. See his attached catalog.

Roger Parent - Aluninum Clutch and E-Brake Pulleys.jpg
Attachments
Roger Parent Catalog 11-02-19.pdf
Roger Parent Catalog 11-02-19
(1.69 MiB) Downloaded 35 times
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

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Re: How to change leaking master brake cylinder.

Post by terribleted »

To fix what you have all you really need is a new master cylinder and the gasket that goes between it and the body of the car, unless the brake line at the master cylinder breaks on removal. I would not try to rebuild that one, as new ones are not terribly expensive and based on your posts your knowledge of what is ok to rebuild and what is not would be limited.

I personally like to convert from a single master cylinder to a dual setup because they are safer like Brad mentioned above. Clark's sells a kit with instructions. Installation requires some bending of existing brake lines under the dash and drilling a hole from trunk to interior to pass the new second line to the master cylinder.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

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65CherryMonza
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Re: How to change leaking master brake cylinder.

Post by 65CherryMonza »

Thanks guys yes I'm considering doing the switch now that you guys mentioned it. It just makes sense.
My cylinders on the brakes look fairly new so I'm not worried about them.

I looked for the conversion kit but I can't find it on Clark's could you point me in the right direction?

Also what's the best way to remove the old one ? Do I drain the fluid from the line that goes to the master cylinder ? I have worked on cars before but have always stayed away from brakes... They intimidate me a bit as they are to important to mess up. But I think it's time to man up... Image

Any tips or tricks would be much appreciated as I'm sure most of you guys here are pro's when it comes to this stuff and learning from other people's mistakes might help me getting this done without screwing anything up.

Thanks again you guys are always so helpful !
terribleted wrote:To fix what you have all you really need is a new master cylinder and the gasket that goes between it and the body of the car, unless the brake line at the master cylinder breaks on removal. I would not try to rebuild that one, as new ones are not terribly expensive and based on your posts your knowledge of what is ok to rebuild and what is not would be limited.

I personally like to convert from a single master cylinder to a dual setup because they are safer like Brad mentioned above. Clark's sells a kit with instructions. Installation requires some bending of existing brake lines under the dash and drilling a hole from trunk to interior to pass the new second line to the master cylinder.
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Re: How to change leaking master brake cylinder.

Post by 66vairguy »

A dual master cylinder upgrade is a good investment in safety, BUT I WOULD NOT USE THE CLARK'S KIT!!! For years folks have complained about the Clark's kit (myself included). The master cylinder is the same as you'd get at an auto parts store for a 1967-69 Corvair. The problem is the Clark's plumbing. They require you to bend the main line from the rear up under the dash and if you kink that you must replace that LONG line to the rear and it's not an easy job. Also the one Clark's line goes way out into the trunk and is easily wacked by items loaded into the trunk!

Some use the 1967 type plumbing IF you can find it. HOWERVER only the 1965 cars used the "smaller" diameter to the rear brake line. 1966 - 69 models used the bigger to the rear brake line. Others just install a "T" fitting with plugs in a hole next to the original "T" fitting. Then the rear line will screw in and does not require bending - easy. There are different fittings to make the 65 rear line work. The hard part is forming lines to go from the master cylinder to the "T" fittings.

So if you are not good at brake plumbing I'd just install a new single master cyclinder OR find someone who can assist you with a dual setup.

Go to the Corvair Center Forum and search for many pics, but here is one link that will show the issue with the Clark's kit and an alternative.
http://corvaircenter.com/phorum/read.php?1,584970

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Re: How to change leaking master brake cylinder.

Post by terribleted »

65CherryMonza wrote:
Sun Sep 13, 2020 10:38 am
Thanks guys yes I'm considering doing the switch now that you guys mentioned it. It just makes sense.
My cylinders on the brakes look fairly new so I'm not worried about them.

I looked for the conversion kit but I can't find it on Clark's could you point me in the right direction?

Also what's the best way to remove the old one ? Do I drain the fluid from the line that goes to the master cylinder ? I have worked on cars before but have always stayed away from brakes... They intimidate me a bit as they are to important to mess up. But I think it's time to man up... Image

Any tips or tricks would be much appreciated as I'm sure most of you guys here are pro's when it comes to this stuff and learning from other people's mistakes might help me getting this done without screwing anything up.

Thanks again you guys are always so helpful !
terribleted wrote:To fix what you have all you really need is a new master cylinder and the gasket that goes between it and the body of the car, unless the brake line at the master cylinder breaks on removal. I would not try to rebuild that one, as new ones are not terribly expensive and based on your posts your knowledge of what is ok to rebuild and what is not would be limited.

I personally like to convert from a single master cylinder to a dual setup because they are safer like Brad mentioned above. Clark's sells a kit with instructions. Installation requires some bending of existing brake lines under the dash and drilling a hole from trunk to interior to pass the new second line to the master cylinder.
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A search on Corvair.com for master cylinder, shows the index. index shows dual on page 145. Clark's online is weak. Next time you order from them get a paper catalog from them....order part number CAT they are free and invaluable. https://ssl.corvair.com/user-cgi/catalo ... w_page=145 Changing the current master is unbolt it take it off, bolt on the new one, and bleed the brake system. I agree with 66 vairguy's assessment of Clark's kit. I prefer to do it more like he describes in most cases. Their kit is just simple for those who do not know how to plumb duals properly.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
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66vairguy
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Re: How to change leaking master brake cylinder.

Post by 66vairguy »

If you go with the dual MC do go online and learn how to "bench bleed" the MC. Due to the installed angle a dual MC is very hard to bleed when new and empty. DO NOT DEPRESS THE PLUNGER TOO FAR WHEN BENCH BLEEDING - you can damage the cups if you go to the stop too firmly.

So you install the MC bleed and full of fluid, BUT PUT DOWN SOMETHING UNDER IT until the the lines are install - brake fluid will dissolve the trunk paint!!

Good luck.

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65CherryMonza
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Re: How to change leaking master brake cylinder.

Post by 65CherryMonza »

Thanks guys with all the helpful advice... I will go with the Clark's Corvair kit as I don't really use the trunk for anything... Might even make a cover for the MC so it won't get hit. I'm pretty good with that sort of thing.

Now I have to bend the line under the dash a bit as you guys describe. If I Fu... that line up can I just order a new one just in case ? If so wich Line is it I need to order...? Is it... C11213 ?

Thanks again guys

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Re: How to change leaking master brake cylinder.

Post by terribleted »

65CherryMonza wrote:
Mon Sep 14, 2020 7:13 am
Thanks guys with all the helpful advice... I will go with the Clark's Corvair kit as I don't really use the trunk for anything... Might even make a cover for the MC so it won't get hit. I'm pretty good with that sort of thing.

Now I have to bend the line under the dash a bit as you guys describe. If I Fu... that line up can I just order a new one just in case ? If so wich Line is it I need to order...? Is it... C11213 ?

Thanks again guys

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That would be the one unless the car has the larger 1/4" line in it in which case it would be C11214. Look and see before ordering.

Straightening and reshaping the front end of the main body line without kinking or breaking it can be annoying. I have been successful with doing this 95% of the time. I use a simple tubing bender (see link below) and a couple pairs of locking pliers. Be careful where you drill your hole to pass the line thru. You do not want to drill things that you do not want to tear up like wires or cables. You also want to be sure than once installed the brake line will not be contacting the e-brake cable, or clutch cables, that run close to this lines path.

https://www.napaonline.com/en/p/BK_7760 ... 5EEALw_wcB
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

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65CherryMonza
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Re: How to change leaking master brake cylinder.

Post by 65CherryMonza »

Thanks for the tips that tube bender looks good it should make it a bit easier... I will only bend it a little bit at the time...!
Thanks again very helpful advise!
terribleted wrote:
65CherryMonza wrote:
Mon Sep 14, 2020 7:13 am
Thanks guys with all the helpful advice... I will go with the Clark's Corvair kit as I don't really use the trunk for anything... Might even make a cover for the MC so it won't get hit. I'm pretty good with that sort of thing.

Now I have to bend the line under the dash a bit as you guys describe. If I Fu... that line up can I just order a new one just in case ? If so wich Line is it I need to order...? Is it... C11213 ?

Thanks again guys

Sent from my SM-N975W using Corvair Forum mobile app
That would be the one unless the car has the larger 1/4" line in it in which case it would be C11214. Look and see before ordering.

Straightening and reshaping the front end of the main body line without kinking or breaking it can be annoying. I have been successful with doing this 95% of the time. I use a simple tubing bender (see link below) and a couple pairs of locking pliers. Be careful where you drill your hole to pass the line thru. You do not want to drill things that you do not want to tear up like wires or cables. You also want to be sure than once installed the brake line will not be contacting the e-brake cable, or clutch cables, that run close to this lines path.

https://www.napaonline.com/en/p/BK_7760 ... 5EEALw_wcB
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Re: How to change leaking master brake cylinder.

Post by terribleted »

That bender is useful in this case to help unbend the existing line spreading the load or more area than you can do by hand. Not ideal in this case but better than nothing
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

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65CherryMonza
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Re: How to change leaking master brake cylinder.

Post by 65CherryMonza »

Hey I got one more question the brake line nuts are imperial not metric right... Got to buy myself a set of flare nut wrenches... So I don't strip anything...
Also what size clear hose is good for bleeding the brakes ?


Thanks in advance !

terribleted wrote:That bender is useful in this case to help unbend the existing line spreading the load or more area than you can do by hand. Not ideal in this case but better than nothing
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Re: How to change leaking master brake cylinder.

Post by erco »

Yes, Imperial, mostly 3/8" IIRC and some 7/16" nuts on the brake diff switch if you loosen those. Don't skimp on flare nut wrenches, get strong/stiff ones like Craftsman. I rounded off a nut with a cheapie/flexy wrench. You dont need flare wrenches to bleed brakes, obvi, a box wrench (even open end) will do for bleeding. I want to say 3/16" ID Tygon tubing for bleeding. Get thick wall hose so it fits tight. Most any hardware store has it.

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Re: How to change leaking master brake cylinder.

Post by terribleted »

65CherryMonza wrote:
Fri Sep 18, 2020 4:57 pm
Hey I got one more question the brake line nuts are imperial not metric right... Got to buy myself a set of flare nut wrenches... So I don't strip anything...
Also what size clear hose is good for bleeding the brakes ?


Thanks in advance !

terribleted wrote:That bender is useful in this case to help unbend the existing line spreading the load or more area than you can do by hand. Not ideal in this case but better than nothing
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Yeah regular SAE 3/8, 7/16, and 1/2 inch flare wrenches. The bleeder screw outlet are about 1/8" diameter so hose that will push on that. I like small aquarium hose which is clear so I can watch the bubbles in the stream. these days I have been using a vacuum bleeder I got from Napa for around under $50. Hook it to the air compressor line and the bleeder and watch the fluid suck thru. Very fast, one person, go around longest to shortest line twice and system is bled. i have to stop and refill the master cylinder after a little bit on each wheel to ensure I do not let it get empty as empty means start over. They have a device that will auto refill the master as you go but I did not spring for that.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
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Re: How to change leaking master brake cylinder.

Post by joelsplace »

If you use a vacuum bleeder you'll have to seal the bleeder threads with some Teflon tape or you will always have bubbles.
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Re: How to change leaking master brake cylinder.

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joelsplace wrote:
Sat Sep 19, 2020 11:38 am
If you use a vacuum bleeder you'll have to seal the bleeder threads with some Teflon tape or you will always have bubbles.
Yes you always see some little bubbles in the bleeder hose while the vacuum is applied. If you watch you can see the bubbles change from big and gasping to small, this usually means that part of the system is bled. You want to barely crack the bleeder open to minimize any air sucking around the bleeder. Nota good idea to put teflon tape on the bleeder screws, particularly with cheap Chinese replacement wheel cylinders, you will just be more likely to over torque the bleeders and crack the castings (they are pretty dam weak having broken more than one). I have found that bubbles in the bleeder hose are not that relevant really. I just suck most of a master reservoir thru each bleeder screw 2x and the system is fully bled 9 of 10 times (pedal solid with no pump up). That 10th time there is either a leak in the system somewhere or 1 more time around and it is good to go:)
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

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