Technical Need advice about removing residual valve from master cylinder

My '48 Cadillac has Willwood disc brakes added on the front. I need to remove the pieces that maintain pressure in my brake lines within my new stock reproduction master cylinder and wanted to get advice on exactly which parts to remove. Attached are pictures of my single outlet MC, and a rebuild kit for it. To disable the residual valve. would I remove the rubber piece on the backside of the hexagonal metal piece only....or do I remove the rubber piece and the hexagonal metal piece. Anything else I should know? Any advice is appreciated.

 

The hex metal piece is the valve, the rubber washer just seals it to the housing. I remove both of them.

 

IF your calipers are higher than the master, you may need a 2# inline residual to prevent fluid drain back to the master.
I would install a 10# inline residual to the rear drum brakes, taking place of the internal valve you are removing.

 

Yes, great idea and thank you. I'm planning on getting a 10 psi inline valve and installing it to maintain that needed pressure to the rear wheel cylinders.

 

I appreciate the tip, thank you sir.

 

- 'WILLY STOP' BRAKE TECH -


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You are going to power a DISC/DRUM setup with a SGL RSVR/SGL OUTLET MC?

And no one else see's the problem here?

Previous post - https://www.jalopyjournal.com/forum...lipers-that-dont-release-well-please.1325352/

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I saw that too, huge red flag. I'd put that master on the shelf and find a properly-sized dual.

 

When will people understand that a single curcuit pressurizes just the same as a dual.

 

To answer your question just pop the innards out of the check valve. You need the shell of it in there to keep the spring centered.

 

Don’t have a dog in this fight but am curious if any manufacturers ran disc/drum combo with a single master cylinder. I’m guessing for safety reasons dual master cylinders arrived before disc brake technology?

 

67 was the first year that US cars had to have a dual MC. Discs were around before that. With single pot masters. The reservoir was pretty large, because fluid is needed to fill the calipers as the pads wear.

Mustang, Disc/Drum:



Corvette, 4 wheel Disc:

 

Yup and yup, despite what people want to believe you can drive a car with a single master without ending up dead.

Early barracudas had disc drum with single reservoirs as well.

 

I just pulled the rubber out of the little hex valve and put the hex back in. Stops on a dime.

 

The difference is those examples were setup from the factory that way. The '48 Cadillac in question was not. Will it work? Probably, it's just hydraulics after all. Will it work well? A lot of people on this board probably put up with worse.

There's more involved than simply pressurizing the system and I think you know that. A dual master, yes, separates the two, but it does so because the two drum/disc designs require different amounts of volume and/or pressure to operate efficiently.

 

Sorry this is wrong, the reason they separated them was strictly safety.

 

Simple enough to do at the brake line after the step down tee to the rear wheels when all four wheels/tires are of near same size. Big and littles you say. A little more creativeness required. Example - one could split the exiting line from the master. Ford got creative and made a master with dual exits vs using a tee. Pic is from Jim posted earlier in this thread. Note, what’s in the backward?

Either way, I’ve never added any proportioning devices to anything. I use only simple brake components having non combination bores.

 

And when will some come to the realization of fluid volume needed in a DISC/DRUM SYSTEM to initiate PROPER disc caliper piston(s) movement as being much greater than a DRUM/DRUM SYSTEM?

If one truly desires (?) to use a SINGLE RESERVOIR MC on a DISC/DRUM SYSTEM, SINGLE RESERVOIR DUAL OUTLET MC's were offered.

- WANNA SEE A GOOD CAR WRECK? - CLICK HERE -​

 

Yes. The DUAL RESERVOIR was introduced in 1967 by FEDERAL MANDATE.

The single reservoir (DISC/DRUM) was also referred to as a 'FRUIT JAR' as to the increased size of the reservoir needed for the front disc circuit (fluid volume).

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You're wrong. Most of the guys here know it, but you don't...

fwiw, the original single drum MC on my 62 vette which I added front and rear discs to, stops the car with very little pedal movement.

 

IF the MC is matched to the vehicle braking system.

Nothing like a steering wheel imprint on the forehead and rib cage along with missing teeth.

That and new front sheet metal primed will be a big hit at Mels' on Saturday night.

 

- H.A.M.B.one's 'WILLY STOP' BRAKE TECH ASSOCIATION -​

Most of the guys here haven't the first clue.

 

You'd be surprised.

 

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Now, I wonder why FORD did that?

Something to do with the needed RPV in the rear drum circuit I think ...

... nah ...

According to the 'WILLY STOP' BRAKE THEORIES practiced here, there is no need for RPV's ...

Now why did they use two outlets ... if I could just remember ...

We keep this up and I am going to have to run-out for more beer and poppy-corn ...

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I don't think much would surprise me after reading through this thread.

I think it is the best one so far ...

 

You are wrong, most guys here do know.
Seems to me when someone here on HAMB doesn’t know something about brake systems you jump in and belittle several people and only muddy the waters. I don’t see you suggesting a solution in a respectful manner that is helpful. My suggestion is to be helpful or don’t reply. Yes there are many single pot disk / drum systems, they work, I have one and it is very effective.
Dan

 

Do any of your residence states have an annual vehicle inspection on these cars you are running?

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TO WIT -

If you have muddy waters maybe you need a brake fluid service.

You can lead a horse to water, but ... well, you know the rest.

If I make a suggestion, the WITCH HUNT begins.

You know, ASE has education info on the inner-screen for free. Maybe start there.

What upsets me is a novice comes here asking for knowledge and the replies given are scary.

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No you 1st said a single pot mc is a problem, then you said well if it’s OEM .,.., you could have suggested to the OP that a dual reservoir is a better set up and here’s why…., or heres why a residual valve should or should not be used…. Etc etc etc. the only witch hunts I’ve seen on HAMB really aren’t which hunt but as-hole hunts.
Good day
Dan

 

You know, what you have just posted makes absolutely no sense.

I simply asked if anyone saw a problem. One poster replied his seeing it also.

The usual 'WILLY STOP' BS session began after that.

 

Looks to be inline for the rear brakes, most likely some kind of proportional valve.

No.
This is a false statement.
Plenty of disc/drum and disc/disc systems that use the same size or smaller MC bore than a drum/drum system.

Bore size has nothing to do with system type. It has to do with system pressure requirments.