66 Monaco single brake reservoir to dual

66MonacoWagon

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I've done some searching through the threads and can't find exactly the info that I am looking for...my single master cylinder (PB - drums) has started to seep at the base so it is probably time to change. I will convert it to a dual, but have never done the swap. It there a step by step thread or guide? Obviously I need to know what parts to get, and how best to install. Is it also wise to replace all rubber hoses and wheel cylinders now as well (does the dual mc put more pressure in either the fronts or rears and tend to blow out these parts quickly?) What type break fluid should I run, and do I merely empty the system, or should it be flushed with something? While I am asking, what's the best "1 person" bleeder system that people like?

Thanks! It all might be in a good thread I just haven't come across yet.
Joe
 
Hi,
I took all the 1967 dual components and bolted them into place.

Really what you need is the dual drum M/C and the distribution block from a 1967 C body and be sure to plumb it into place correctly.
If you can't locate the distribution block then you will need to add a metering valve going to the back brakes only and adjust until the rears don't lock up under a heavy application of the brakes
If you are converting to power drum if not equipped already then you will need to change the brake pedal assembly and add a booster from a 1967 C body as well.
Last advise is to plumb the rear pot to go to the front brakes and the front pot to the rear brakes for proper installation
 
20140609_213437.jpg
 
Here is where the metering valve would go highlighted on the right red circle
This was my first attempt without the correct distribution block

the left circle is what you need to either block off as shown here or replace with a 1967 distribution block and plumb all lines into that then to the back
20140609_213230.jpg
 
Inlinetubes inc. has the conversion kit. Pre-bent lines, fittings and block that bolt right in place of the original block.
 
67 dual master, a drum/drum prop valve, and some tube and a bender. Regular fluid, replace limes if needed, bleed system, and drive. Nothing special needed. I had the single master fail and swapped the dual in in about an hour total with dickin' around. My brakes are sub par, I never bled them fully as two bleeder screw heads stripped while attempting to bleed. So I have to pump quick. I'm that lazy that I know about my air bubble and I have to pump. They stop fine, with plenty of power, even with a loose fitting hose to the booster. So if you do it correctly, you should have no problem with the new setup. We'll swap it at Volo!
 
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Joe, thanks for starting this thread, I want to do the same conversion on my wagon. I have the Midland-Ross booster which works fine, is the 67 dual master a bolt-on to this booster?

DSCF2294.JPG
 
That’s my fear locumob, is that I will have to skip Volo. I am no mechanic, so everything I do takes 4x as long. I don’t know if it will make it to Volo, and my passenger is worried about driving in a death trap. I’ve progressively been getting more pull on braking in addition
, so I’m thinking about getting it on blocks and replacing everything at once.
 
Hi,
Really what you need is the dual drum M/C and the distribution block
If you can't locate the distribution block then you will need to add a metering valve going to the back brakes only and adjust until the rears don't lock up under a heavy application of the brakes
Here is where the metering valve would go highlighted on the right red circle
This was my first attempt without the correct distribution block
67 dual master, a drum/drum prop valve.


All you need is the cylinder, some tubing, and a plug for the hole in your current distro block!
I don't know where you people are saying he needs all this other ****? I don't have any of that crap on mine, and neither does he!

66-Monaco. If all you want to do is upgrade, just do what I said. If your not changing anything else on the system, then just get a dual cylinder for drum brakes.
NOW, if you went with a drum/disc cylinder, then you would need a proportioning valve for the rears. Good Luck
 
98812484-2156-4CED-A876-F5027A35F714.jpeg

This is the inlinetube kit for our cars.
No bending tubes or modification of existing tubes required.
Swap this dist. block with existing. Done.
 
I don't know where you people are saying he needs all this other ****?
I tried just going with the stock distribution block, but had issues. Swapped in the dual circut block and all is good. Glad you didn't need it, I did.
 
All you need is the cylinder, some tubing, and a plug for the hole in your current distro block!
I don't know where you people are saying he needs all this other ****? I don't have any of that crap on mine, and neither does he!

66-Monaco. If all you want to do is upgrade, just do what I said. If your not changing anything else on the system, then just get a dual cylinder for drum brakes.
NOW, if you went with a drum/disc cylinder, then you would need a proportioning valve for the rears. Good Luck

Hi Stubs.
I did what you did and it does work as long as you never have to jam on the brakes in a panic situation.

I had a lower brake pedal with my original dual setup (as shown above) and one day I have to brake hard and fast and the back end of the car nearly came around to meet the front and I was only going about 20mph. I was able to source an OEM valve and added it to the system. it worked perfectly.

What I experienced is a rear wheel skid which equals a car out of control...

Without a metering valve or OEM distribution block you are driving with less than a factory balanced braking system that may cause you to crash.

https://www.quora.com/Why-is-metering-valve-used-in-braking-system

If anyone does the searching here on the FCBO or google there is tons of information and threads on this very subject already.

But if you are convinced that your way is best, take a video of the car and have the videographer stand on the side of the road as you drive by and brake hard.
You will likely see the rear wheels lock up and the fronts still rolling.
This should end the debate on the required valve or not (at least for your setup on your car)
 
Thanks to all so far. I have ordered the master cylinder, new rubber hoses, and wheel cylinders from rock auto. I ordered the conversion kit from inline tubes (steel lines and distribution block). Now I just gotta wait. I want to be prepared for everything so I don’t have to dive into the hydrolics but once...
 
Hi Stubs.
I did what you did and it does work as long as you never have to jam on the brakes in a panic situation.

I had a lower brake pedal with my original dual setup (as shown above) and one day I have to brake hard and fast and the back end of the car nearly came around to meet the front and I was only going about 20mph. I was able to source an OEM valve and added it to the system. it worked perfectly.

What I experienced is a rear wheel skid which equals a car out of control...

Without a metering valve or OEM distribution block you are driving with less than a factory balanced braking system that may cause you to crash.

https://www.quora.com/Why-is-metering-valve-used-in-braking-system

If anyone does the searching here on the FCBO or google there is tons of information and threads on this very subject already.

But if you are convinced that your way is best, take a video of the car and have the videographer stand on the side of the road as you drive by and brake hard.
You will likely see the rear wheels lock up and the fronts still rolling.
This should end the debate on the required valve or not (at least for your setup on your car)

I'm runnin 4 wheel disc, and I DON"T have a problem! Car stops better then stock! The only problem I have is that I'm now at 5000' and can't adjust to compensate for vacuum loss which is fine at sea level. Beside I don't have plates or insurance on it so that ain't nothing going to happen about filming anything! Why should I?
I'm just telling you what works for me, but it seems you have a problem with it, fine. "You do what you do, and I do what I do"!
 
I'm runnin 4 wheel disc, and I DON"T have a problem! Car stops better then stock! The only problem I have is that I'm now at 5000' and can't adjust to compensate for vacuum loss which is fine at sea level. Beside I don't have plates or insurance on it so that ain't nothing going to happen about filming anything! Why should I?
I'm just telling you what works for me, but it seems you have a problem with it, fine. "You do what you do, and I do what I do"!
Well there you go and you are correct that your setup for all wheel disc brake conversion likely is set perfectly for your car, no need for a distribution valve.

The original question asked here was and is about changing from a single pot master cylinder to dual retaining the original drum brakes

My responses and comments have been based on the question asked as to what is required to do this successfully.

My responses to you were based on the assumption that you were running drums on all 4 corners as well.
Your comments seem to be containing an aggressive tone defending what you did to which has me wondering why but there is no need to clarify on this point.
I certainly don’t want to strike up any arguments on what’s best
I do agree that a full disc conversion is best


I’m just trying to help the members out with good advice and a successful modification the first time around.

Good luck to you with the elevation changes & the vacuum boost
 
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It's just that everybody give vague and a total lack of all information about what they are doing makes it confusing for everybody. So everybody starts spewing out crap that's not needed because the original post contains a lack of info, so they assume the worst which is wrong and spew false info.
Due to a severe financial hardship by the V.A, my car will stay unregistered and uninsured until my life gets better. And by then, hopefully I will be at a lower altitude and have the coin to get it back on the road. Just sayin
 
You really don't need the switch (distributes nothing fluid is always kept separate, hence the reason for dual system). The switch moves about a 1/8" giving you that "oh ****" moment of no pressure in system, then it hits turning on the brake warning lamp ( like you haven't already figured out there is a problem) and you come to a stop on whichever half is working.
The dualmaster cyl has a compensation port that equalizes pressure front and rear. If a panic stop results in rear wheels locking first the proportioning is off, corrected by reducing brake power on rear wheels (linings, drum size, wheel cylinder size)or a simpler way is a valve that cuts out pressure to rear (proportioning valve). The stock valves, if equipped, either stand alone or combo with switch are really not that effective and most being 40-60 years old probably don't work anymore.
The easiest way is to duplicate the later system.
If your cheap and determined run the back port on MC to front brakes and front port to rear brakes.
 
1965 C-Body Dual Master Conversion - Master Cylinder Lines with Block
CDB6503 - Stainless $79.00 or OEM $69.00
Starting to think about a partial brake overhaul and flush on my 66 wagon. I intend to get this line and block kit and add a dual master. I have seen reference to using a 67 unit, can anyone confirm a specific source and part number that will fit my Midland Ross booster? Are these dual masters available new or just rebuilt?
 
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