Bumping and old thread....

Can someone tell me from this picture what part# is the residual pressure valve??

Thanks in advance

 

Hi Jim,

The part number of the valve would be (if I am reading my copy of the parts book correctly) is 91A 2178-A. If not hopefully someone will chime in and correct me.

I forgot I started this thread.I eventually had to replace the master cylinder I rebuilt because it started leaking again. I went with one from NAPA. It is a single cylinder, and I should of replaced it with a double.

 

I am actually replacing my single Mc for a 67-68 mustang dual manual mc and some says it needs thebtrasidual valve and some.says it doesn't. The.new one has no residual valves at the ports so. So I just wanted to make sure there was a check valve in the old system.
Now the question is.......is there a check valve inside the new cylinder or.do I haveto go for inline.valves???

 

Jim, I looked in an old Chiltons Auto Repair manual of mine, specifically for the years 1964-1971. I looked at the Mustang Dual master cylinder diagrams ,one diagram is for disc and the other diagram shows the master cylinder for drum brakes. Both diagrams are showing that both the primary and secondary outlet ports should contain "valves" which I am assuming is an inline check valve. It goes like this, the brake line fitting connects to the tube seat. Next the valve goes in behind the tube seat and after the valve there is a spring to push the valve, and tube seat together to the brake line fitting. So it looks like you would put the spring into the port first, then the valve, then the tube seat, then attach the brake line. The diagram shows the valve has a smaller nipple that slides inside the rear of the tube seat. I hope this all helps! I would post the diagram from the book, but I am not sure how. I am sure we could have others weigh in here with much more experience and knowledge than me!

 

Thanks Hooler

I made some digging last night and it appears like that old Master cylinders where equipped the way you decribes, however is seems like if one buys a part replacement or new aftermarket replacement then the residual pressure valve is mostly replaced with a hard machined inverted flare and then the port residual valves is no longer possible to add. Then one haveto go for a set of inline valves.......

Bummer

 

That makes sense. Then there must be after market in line valves. I know there are aftermarket proportioning valves.

 

Is there a dual MC that bolts to the original location or would I need to make a lot of modifications for one to work? What dual MC do you guys recommend? I was heavily debating on rebuilding or replacing my '56's original MC.

 

From what I found out when I did my research I couldn´t find any dual MC that would place it in the stock location.

So I hade to make it like this to get everything to line up with the filler hole in the floor and skipping the offsetting kit

If you look thru these post from the bottom up you will understand what I did

DinnerHill SpeedShop: Brake system

 

Hey Jimmy, you are doing some great work and I am learning much and enjoying your build thread. Keep the great information coming.

Resurrected, I am still kicking this conversion around in my head too
I don't really have fab skills or the tools to modify things so I am quite limited to bolt on solutions. One I was looking at was the dual MC from Mid-Fifty
Its part number is 5914 and its mounting bracket kit is 5912. Its just what I have looked into. I haven't even called them and talked it out with them to make sure I am on the right page on this. I just wanted to let you know it could be a possibility.

 

Thanks for the kind word.

Those are the exact same parts that I based my conversion on. They state it will place the Mc under the original filler cap but that's not quite true.
That mc and bracket will place the mc centerline offset towards the Trans. They have a offset kit, witch includes a longer clutch shift and a more narrow u bracket, the one between, clutch shift end and Trans mount.
However that solution will transfer the pedalforce to the mc pushrod thru bendingen a bolt......in my engineering eyes, not very safe.

If you can use an measuring tape and an angle grinder, you are halfway there. Then just hire or ask a friend if they can weld it together.
If you want more input on how I did, just let me know and I will do my best to guide you thru it.

 

Modern dual circuit MC have a different mounting pattern than the earlier underfloor MCs, so an adapter is required. Mid Fifty has the kit for the conversion. I have a nearly new non-boosted kit installed in my 56 that I've since changed to hanging pedals with boosted MC. I'd be willing to sell all but the proportioning valve which is for disk/drum setup. PM me if interested.

 

Thanks for the info! That's what I'll do. Shouldn't be too hard to make bracket for the MC. What's the recommended "modern" master cylinder to use? Is there really a difference?