# 69 GTO Manual drum brakes



## pontiacmatt (May 19, 2013)

Planning to replace master cylinder and a few brake parts due to age. Last master cylinder change was about 20 years ago. I remember unhooking push rod from brake pedal to remove it but don't remember how push rod and boot were held in place on the new master cylinder to reinstall it. Just asking before I get started.


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## BLK69JUDGE (Jun 10, 2010)

I thought manual drum brake masters just fell off the firewall once the 2 bolts were loose ???
I dont think you even need to be under the dash .... 

Buy a master with bleeder valves so it looks original

or if your looking for an original .I have one.. I can send it to https://whitepost.com/#hometop for a rebuild

it might even be time for a power booster ... depending on your driving conditions ... habits..the driver.. and
the originality of your car ... oh and maybe your motors vacuum ....

Scott


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## 1969 tempest custom s (Sep 9, 2020)

I just did a break job on my own 69. It may depend on what parts are still with the master cylinder when you install the push rod. First, get the service manuals. origonals if you can because the repro ones have blurry or bad images. Parts manuals help too but the cost of repro parts manuals are still very high.

Vendors also sell the repro parts you may need. thier catolog pictures can help you to determine if you have all the parts. How ever the clevis pin that attaches the push rod to the pedal , on my car anyway is NOT retained by a cotter pin but by a spring type of retaining clip. so be aware of that when looking thru the catologs of various vendors.

The push rod sits in the back of the master cylinder. If you have a manual type master cylinder the rod goes in to the back of the piston about an inch. If your master cylinder is set up for a power brake application the hole in the back of the piston is only about 3/8ths of an inch deep. Probably not a problem but just to make sure you start with a correct master cylinder.

The rubber boot on the back of the master cylinder is sold as part of the M/C in some rebuilt cylinders but not others. It is also sold as part of M/C rebuild kits.... but not others. It is sold separately by some vendors but not others. due diligence there.
There is a third part called a Master cylinder push rod retainer. PN R129TQA sold by Ames is the only one I am aware of that is for sale. It performs the same function as the factory one but does not look like it. No problem because it is burried up under the dash and is covered by the rubber boot. It is an important part because it keeps the push rod seated in the back of the M/C piston so it will not fall out.

The correct clevis pin and retaining clip is also soled by Ames pn# R139B. They also sell an incorrect version that uses the cotter pin rather than the retaining clip.
The rubber boot aka Master cylinder rod boot. is sold by various vendors separately and if you shop around, it comes on some new or rebuilt M/C's and as part of rebuild kits sold by various vendors.
The push rod is also sold separately. bare in mind that there is a different length for either the power brake application or the manual brake application.
Obtain the service manuals to determin how to correctly install the entire assembly but also get several vendors catalogs to seek out those parts that are correct.


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## O52 (Jan 27, 2019)

I also did this on my 68 manual drum brake car. The original master cylinder for 67-72 manual drum brake cars does not have bleeder screws. However the power brake MC does. It really doesn't matter which one you use but the pushrods may be different lengths. 
Make sure to reinsert the pushrod clevis into the lower hole of the brake pedal for manual brakes, upper hole for power.
The manual brake master cylinder is common throughout the GM A and F body cars.


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