Technical Replacing Master Cylinder

What rookie mistake or petty oversight might i make when swapping out a master cylinder with a dual master cylinder?

 

Have you ever done one before?

 

What vehicle, drum/drum or disk/drum?

You'll want a smaller diameter bore in the dual, since each section is now pushing fluid to just two wheel cylinders instead of four. Also make sure you bench bleed the master before installing it.

 

Biggest thing I can think of is not knowing how to double flare brake lines after you cut them.

Charlie Stephens

 

Never actually swapped one out myself no but i feel comfortable doing it.

 

...then there's the issue of the residual valves...

 

54' Customline Im assuming drum/drum just means drums all around, yes. So should i use a MC from a different car?

 

Here is what it looks like now. What MC should i replace it with ?

 

42-42886-1 from Macs, suits drum drum torino/ fairlane etc. Have just ordered one myself for a drum / drum set up. $72.95.

 

WIll i need to modify the rod on this one to adjust for the pedal? is that a "thing" anytime you replace m/c?

 

I think i read something about that? Could you elaborate?

 

you don't need them if the master is on the firewall
only when it is below the wheel cylinders and calipers.

 

Are we talking Residual Valves here?

 

The one 32Tub suggested fits a number of 68/mid 70's Fords.

Outside of the obvious things such as running lines for both the front and rear brakes you may have to come up with a new or rework the push rod to work with your pedal assembly. the whole thing isn't rocket science but you do have to do some thinking on it to have it all work.

If you just have a bad master cylinder and only want to replace it I see that replacements are readily available for around 60.. That woudn't give you a dual master cylinder but would solve the bad master cylinder issue.

 

yes, sorry

 

You won't need residual valves as your master cylinder is well above the wheel cylinders but it will need some adaption ie re drilling firewall holes and maybe changing pushrod length ( which may be ok but you wonn't know until you fit it all up)

 

Im assuming that i'd have to replace the lines since their independent now or can i still get use out of those old ones?

 

Here's some for less money...
https://www.rockauto.com/en/catalog...,1435664,brake/wheel+hub,master+cylinder,1836

You won't need add-on residual valves, they're already built-in. As noted, you'll have to make sure the pedal rod isn't too long or short. The modern masters really aren't set up to operate a pressure brake light switch, this would also be a good time to switch to a mechanical type.

You'll find that your stock lines are 'teed' right where it drops down to the frame, you'll need to split them there. The new master will bolt right in place of the stock one using the two lower bolts. Do reinstall the upper bolts to properly attach the pedal assembly to the firewall. This isn't a overly difficult swap, but is a bit tedious; if you've never done one, figure it for a weekend job.

 

assuming you meant 65 mustang master, I believe that is a single jar type known as the "fruit jar" master cylinder, they work fine, but if you keep a single reservoir master can you just get a new one like you have now? That way you can just swap it out like Mr48said
If not the ones above posted by 1932 Tub are the correct Ford drum drum master cylinders.
You would need to mount them to your current brake pedal, and yes the pushrod would need to be changed, as well as the lines to the front and rear, you can add a "T" tot he lines to accommodate the brake light switch too.
You would need to be able to double flare and bend brake line.

Your car would be fine with replacing the stock one, no need to over think this.
Unless you change the brake type from drum to disc just swap it out.

 

My concern was more on the issue of losing all brakes which is how i realized i needed to swap all this out. Lost all brakes almost wrecked ... crazy.

 

Yep, the dual master will help with that... You'll need a cutting/flaring tool, and a set of flare nut wrenches are highly recommended.

 

The Ford hole spacing is either 3.20" or 3.25" depending on what you read. The Mustang type will bolt up, use the lower bolts only. Measure your existing rod from the back of the master. The new one, adjust it to the same length.

I did my '59 using a Speedway master and CPP proportioning valve, but your conversion is easier using drum-drum brakes.

 

I bought my flaring tool and bender from Eastwood, works well.

Keep in mind the you would also need to bench bleed any new master cylinder, the newer ones come with plugs so you can fill it and depress the plunger to eliminate air before you add it to your new lines.


Found this video cant get any easier than to watch how to on a car like yours....


there are 3 parts this is 2