Single to Dual Master Cylinder Conversion Complete. 1964 Pontiac Catalina
 

I have recently completed the conversion of my brake master cylinder in my 1964 Pontiac Catalina from a single reservoir to a dual reservoir. I have been asked by members to provide details. This is the way that I did it, your results may vary. I excuse myself from any liability in modifying your original brake system using my method.

This is the "preliminary" conversion. Now that I know what I need, and that it works, I will fine tune it in the weeks to come. Basically, I plan on tidying up my new brake lines, to make it more presentable. You'll see in the final picture that I ended up using one 20 inch and one 30 inch brake line. I will probably redo this with 2, 20 inch lines. Here is the basic info:

Originally I started with a single master cylinder with 4 wheel power drum brakes:
http://www.flickr.com/photos/8293453@N08/4883527875/

1. Materials:
http://www.flickr.com/photos/8293453@N08/4883529389/

In this picture you will see the master cylinder I originally purchased from O'reilly Autoparts, but returned due to it being defective. The small allen head screw at the very end of the master cylinder was stripped and leaking. This was a Cardone rebuild. I then purchased a Fenco rebuilt cylinder that did not have this screw, and was in fine shape.

A. Master Cylinder Autozone M-1328
B. 2, 1/4 inch brake lines. These have ends that are 7/16-24. SAE Inverted Flare. (NAPA). I used one 30 and one 20 inch. You may use any length that you desire.
C. 9/16-18 Male to 7/16-24 female adapter Carquest (part number unknown) (Not Pipe Thread!)
D. 1/2-20 male to 7/16-24 female adapter (Not Pipe Thread!) NAPA
E. 7/16-24 male plug. NAPA (Not Pipe Thread!)
F. Female 7/16-24 to female 7/16-24 "barrel" connector. (Not Pipe Thread!) Carquest
G. Dot 3 brake fluid.

I didn't exactly do this in these steps, due to my bad new master cylinder, but this is how I would do it if I did it again:

2. Procedure:

1. Remove existing master cylinder. Look at the hole where your brake push rod enters the master cylinder. If there is a hole that is over an inch long, then it is the deep push rod. If it is just a divot, then it is the shallow push rod.
2. Remove the brake line at the distribution block that goes to the rear brakes, and the line that goes to the original master cylinder. Soak these connections in PB Blaster several days before you attempt to remove.
3. Insert the "plug" into the distribution block where the original rear brake line connected.
4. Insert one new brake line into the distribution block where the original master cylinder brake line connected.
5. Using the barrel connector, connect the other new brake line to the existing brake line going to the rear brakes.
http://www.flickr.com/photos/8293453@N08/4883531871/
6. Loosely install the new master cylinder in position. Check to see the pushrod fits correctly. I didn't have to make any adjustment to my push rod.
7. Bend the new brake lines to your liking. I just did it by hand, because I don't own a tubing bender. Take your time. The line going to the rear brakes connects to the front output of the master, and the line going to the distribution block goes to the rear port of the master. Your front brakes should always connect to the port that is nearest to your brake pedal.
8. Once your lines are bent to your liking, remove the master cylinder and bench bleed it. THIS IS VERY IMPORTANT. Even though I thought I bench bled it thoroughly, I still had air that I had to deal with.
9. Reinstall the master cylinder, and install the correct adapters needed to connect the brake lines. Have a helper depress the brake pedal then tighten the connections at the master cylinder. RESIST the temptation to jump in the car and "test" the brakes. If you do, you'll draw air into the master and have a fun time bleeding the system.
10. Take your vacuum bleeder and throw it in the trash. Call your wife to come out and help you. It worked a million times better. Bleed your brakes from rear right, to rear left, to front right, to front left. Make sure you don't run out of fluid in the master cylinder.
11. Test for brake pedal firmness, and go for a slow test drive. If you're like me, you'll realize that you STILL have air in your system, and will have to bleed again tomorrow.


Completed conversion: http://www.flickr.com/photos/8293453@N08/4883530859/

Again, your result may vary. I enjoyed this project, and feel better about taking my wife and daughter out for a drive now.

As you may have noticed, not one single store in my area had ALL the parts that I needed. You will probably have to shop around. Don't hesitate to ask me if you have any questions. I am by NO MEANS an expert, but even a blind squirrel gets a nut every now and then.

Thanks for reading,

Good luck!
Matt K.

Thanks for the writeup Matt! If I ever get around to working on my car, it will most certainly be helpful.

OK so the line closer to the booster goes to the front brake distribution block and the other one supplies the rear brakes, correct?

Nice work. Remember what the Master Cyl. set you back?

Good stuff here!!

mkoser, couple of questions:

1) for specifically what application (year/make/model/options) did you request the m/c?

2) total cost of parts?

3) just to clarify: you retained the OE junction block and used the rear half of the new m/c to supply fluid to the rear wheels (please confirm).

...it would seem unnecessary to fit a 'proportioning' valve when retaining an all-drum system.

4) how many miles have you driven the car in the new config?

Would you say that under the full range of brake application (easy, panic, etc.), that they feel balanced (no new amount of nose-dive or rear wheel skidding, etc.)?

This is just the type of information I needed to do my 64 Catalina.
However, I too would like to know for specifically what application (year/make/model/options) did you request the m/c?
Thanks for the great job!
Mike.

Looks like that thread is from August 2010 so he may no longer check his PY account.
I got mine at Advance Auto Parts and it's for a 1969 Bonneville with 4 wheel drum brakes. No portioning valve is neccessary for drums brakes, I guess because the front wheel cylinders are larger than the rears? You may have to adjust the plunger rod.
When I first did mine the brakes were full on. I had to shorten my original push rod.

I normally tell them it's a MC for a '69 Camaro ss/rs, or '69 Bonneville

-r-

Get a Master for a 67/8 Catalina and it will work. At least it did on my 65 G/P.

A disc master will retain pressure on the front brake port.

And how do you know how much to shorten or otherwise change the push rod?
Thanks again.
Mike.

Push rod may not need changed depending on which master you use.

Yes, the line closest to you always goes to the front brakes.

I want to say the Master Cylinder was around 25 bucks.

I'm still having problems with adjustment, but I had those before I did the swap. I was using OLD shoes that at one time had been rusted to the drums. I'm confident that new shoes this spring will solve my problems. Otherwise, it brakes fine.... The same as when you drove it this summer ;)

I used a M-1328 master. Did not need to adjust my push rod at all.

Sorry I have been away! Been busy. We added a daughter to the family in September, and work has been insane!!!

Thanks,

MK

Right, you've got to specify that you need a drum/drum master. A disc will hold pressure to the front wheels, and cause sticky brakes.

MK

That is a great write up. I want to do this to the 62 wagon. Will the same procedure work? I just don't feel that safe with the single reservoir. Total failure if one brake line gives out...

Thanks in advance,

Dave

I've never worked on a '62, but I'd be willing to bet that it'll be close to the same.

I'd start by taking off the master, and the connections at the distribution block.

Take those parts with your to your parts seller and compare to what they have.

Once you get all the parts, just put it together.

It'll work the same, just don't know if all the connections are the same size (I'm betting they are.)

Front or rear brakes only is not the best situation in any case, but it having a built in back up in our old Ponchos sure makes you feel better.

Thanks,

MK

Yes it does. Especially when the car weighs more than 2 tons!! I looked at the pictures and it is almost identical to the 62. I guess that this is dependent on the rod size and bore depth. I have to rebleed the lines as the bleeder in the MC was a touch loose and it got drained of fluid.

So if I am going to rebleed, I might as well put 50$ into it and have better stopping and a back-up!!

Dave

The procedure is the same for the 62. I have this about 40% finished. Meaning All taken apart. I am getting the hardware and lines. Then put it back together as the first post. Pretty easy. Well really easy now that I have the engine out of the car!!!

SMOOTH install. Other than bending the new brake lines. I am getting better, but that is an art. But it just goes with the rest of the car. Pissed OFF!!!

I found that the brake booster in the car is from a newer car as the hardware is metric.. Oh well. It works. I bench bleed the MC, but the rear (front brakes) reservoir needs more blleding as it was not pushing a lot of fluid in the air as the front was. No biggie. I will just have my wife push the pedal longer.

Thanks for the help. I feel much better going to stop the car when the engine is done!!!

Dave

http://i689.photobucket.com/albums/v..._brake0008.jpg

Gentlemen:
I am finally getting around to changing out the master cylinder on my 1964 Catalina with power drum brakes. I went to my local brake and clutch excahnge and they fixed my up with a dual master cylinder from a 1967 Chevrolet Biscayne. It fits just fine but they is absolutely no room near the fender for the tubing to come out. I have been looking at the pictures from mkoser and there seems to be plenty of room for his installation. He did use a different master cylinder but I can't see from the picture that there were be any difference in the size of the body of the master cylinder. I am totally confused now. His post says his car is a 1964 also, but I don't have the room he does. What am i missing? Help!!!!
Thanks in advance.
Mike.

That was my issue as well. I went through a lot of scenarios and after much discussion with myself, I decided that the BFH was the fix. Although this might not be the best route. My car was already kinda hacked up so it was no big deal. The other thing I might suggest is getting an A-body Booster and perch. That way it will bring it up and out of the way.

http://www.yearone.com/images/parts/b/bg111.jpg

http://i689.photobucket.com/albums/v..._brake0008.jpg

What booster are you using? I don't think a Chevy booster will work and that is probably what your issue is if you are using that.

Just from looking at the cars in the yard when I went to get my distribution block, the boosters for the '67 and up cars are the same on A and B body. All much larger than ours.

Best bet is the '68 Catalina Bonneville MC & your existing booster.

http://forums.maxperformanceinc.com/...pictureid=5559

I used my existing booster and a Master Cylinder for a 1969 Bonneville with drum brakes and there is plenty of clearance for the lines to exit and bend without kinking.

Thanks a lot guys. I am going in right now to my brake and clutch guys and show him all of this information.
As always. Pontiac guys come through.
Thanks again.
Mike

Here's the one I bought:
http://shop.advanceautoparts.com/web...1289052042____

Anybody done this and done the scarebird disc set up on the front? If so what else is involved as far as plumbing goes.

On an A-body. Not a full size. Let me know if you need some advice.

Dave

From what I have picked up on this forum, you will need a portioning valve and a front disc-specific master cylinder. The rest is the same as stated previously under this topic.

Yeah, Mine was really tight. I bent all the tubing by hand (need to re-do it, it looks bad). I bent a "90" on the one fitting, just to get it in there. I didn't kink it, so it seems good to go.

Hopefully I'll detail under the hood this year.

Thanks,

MK

Is there any difference between the Master Cylinder Autozone M-1328 booster and the Cardone one (10-1363) from Advance Auto that MOJO used? I am planning on putting it on my 63 Catalina. I checked and they both seem to be made for a 69 Bonneville.

I don't think there is a difference. When I was shopping for them, they were the EXACT same unit, with two different part numbers, in two different boxes. I just cited the 1328, since that one seemed to be in stock in most places.

MK

Ok sounds good. Thanks for the info. I will be starting to round up parts in the next couple days to get this started.

So I ordered my master cylinder from Advance Auto ($29), lines and fittings were all from Napa ($18). Not a bad deal for a little peace of mind.

Yup, cheap insurance. I think that I paid the same. I ordered a 67 Catalina MC from Rock auto. Was about the same... I bought premade lines and bent them..

You got a MC for a '69 Bonneville for $29?!

Bruce 28.00 my cost for a drum master from Carquest. 1969 Bonnie.

Just wondering where you found, or was told this information? All of my GM Pontiac shop manuals and assembly manuals show and state that the front brake line goes to the front port and the rear brake line goes to the rear port of the master cylinder. Bob

No, that is incorrect. By design, the piston, or brake line connection, that is closest to the driver HAS to connect to the front wheel cylinders. This is to ensure that braking first occurs on the front wheels, then pressure built in the master cylinder forces the piston farthest from the driver to apply fluid pressure to the rear wheel cylinders.

Every dual master cylinder that I have ever seen is designed this way. Some newer cars split them left and right, but this is not the case in our old Pontiacs.

Thanks,

MK

I should clarify, I was a bit tired when I wrote this last night. Anyway you hook up this master in a drum/drum configuration will work the same, since equal pressure is going to the front and the back. With that said, when they were designed, it was designed to provide full pressure, and longest stroke to the front brakes by way of a MECHANICAL connection from foot to hydraulic piston.

On disc/drum cars with a proportioning valve, the rear port must be connected to the front brakes, and the front port to the rear brakes.

Also, the biggest reservoir always is for the front brakes.

MK

I was going to say that the Tempest has been wrong for years if that was true!!! LOL!!!!

I will say that the Tempest has had discs in front for the better part of 3 years. driving a drum/drum car takes some getting used to. The pedal travel on drum is shorter to lock the brakes up!!!

I am going to swap out to disc soon. BUT the above post for dual is dead nuts right on!!!!!!

Dave

I find it interesting you claim as incorrect, and choose to ignore, information in the Pontiac Service Manual regarding dual master cylinder brake systems for 1967 and up classic Pontiacs. The information I stated is correct. The front port of the master cylinder feeds the front brakes and the rear port feeds the rear brakes and, accordingly, the master cylinder pistons are specifically calibrated, respectively. The engineers purposely used different size fittings for the front and rear ports of the M/C to prevent the brake lines from being installed to the wrong ports. It’s in the manual and it’s written by the GM engineers who designed the system, so you shouldn’t be dismissing it as incorrect. This info is correct for the A and F body cars, as well, and applies to manual, power, heavy duty power, and disc/drum brakes systems. I’ve been working on Pontiacs and Chevys since the early 60s and have never had a problem because of following the proper service manuals. You need to correct several things to have a safe and efficient brake system on your 64.

So is there any ill effects from the rear port feeding the front brakes? I currently have it set-up that way..

This may be (and probably is) true for drum/drum cars, but what about disc/drum cars?

A quick google search came up with this article http://www.auto-repair-help.com/auto...r_cylinder.php

I'm not going to disbute your shop manuals, or you, but any car with a dual master set up that i have seen has the rear port to the front brakes, and the front to the rear. In the event of a leak, you want the FRONT portion to build pressure faster than the rear. If the front portion was at the front of the master, and you had a leak there, the rears would set up hard, and now, possibly causing your car to skid. You want the rear brakes to be fed by the end of the pedal travel, in a front leak situation, to effect a slow and controlled stop.

As far as proportioning goes, on these drum/drum masters, (our big ponchos) the proportioning takes place at the wheel cylinders, not in the master cylinder. The front and rear wheel cylinders are of different diameter.

Just my .02, can't find any info either way to show I'm right or wrong. Use it as you see fit. I've got my 64 plumbed this way, it it stops on a dime.

MK

Ditto.....Got to be careful when selecting master cylinders.. I bought one for a 70 something Gm/factory disc-drum ...it had a large/huge front resivor in the master cylinder..I would run out of fluid if I used the "small" rear fluid resivor for the much larger front disc calipers ?? JMO....Comments..
I'm getting ready to do a 4 wheel disc conversion now..all will change.

Hello guys, just throwing a little parts info out there. In the May muscle car review under new products. Speedway motors has a corvette style master cylinder that is drilled on both sides, so that you can hook up your lines on either side. The cast iron version is 49.00 Item #:91031321 I may look into this when I do my swap. We will see.

FYI: This may have been covered already, but when running the brake lines be sure not to create "traps" (like the ones under your kitchen sink only in the upwards direction) where air bubbles can collect. I did this at first coming out of the MC due to slim clearance. I had a hard time bleeding it all out so I shortened the original brake line and rolled the one coming out of the MC downward so all the air would return to the reservoir and bubble upward and out.

Sounds like the MC mentioned above will be the best situation for us moving forward.

Remember, this above mentioned master cylinder is for DISC/DRUM brakes. It won't work as a simple drum/drum dual master upgrade.

mk