Brake conversion 64 Daytona

[ajarman]

I recently changed the front drum brakes on my 64 Daytona to disc. . From the very beginning it has created problems. First I changed the master cylinder to a unit that replaced the old unit in the car, brakes to the floor. Next step, I changed the rear wheel cylinders and added a 10# residual valve to hold pressure, pedal still goes to floor, and only holds after pumping the mc. This is not a power assist brake system. What am I missing? Do I need a mc with more throw? If so which one should I use?

[Bullet]

I, too, am interested in the answer. But just wanted to say what a beautiful car and an "R" car to boot! WoW.

Mark

[41 Frank]

If you have no pedal you must still have air in the system somewhere, time to bleed brakes again.

[2R5]

did you put in a preportioning valve in the rear line?

[IMG]

Home of the Fried Green Tomato
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1966 Daytona

[BobPalma]

Gorgeous car. Anthony; congrats!

My initial reaction is that you did not properly and thoroughly bench-bleed the new master cylinder before installing it. If that is not done correctly, you'll never "get" a pedal with the unit in the car. [8D]BP

[ajarman]

No proportioning valve but I did put a 10 # residual valve. A proportioning valve shouldn't make it go to the floor, wouldn't that just pressure to the front disc, still got to pump to get it stopped.

[ajarman]

Thought it was bench bled pretty good, I'll try it again.

[52 Ragtop]

Check the adjustment between the M/C and the linkage, if you have too much play, you'll have a low pedal and poor brakes

[struckinc]

there is no adjustment on the daytona. the throw rod is a fixed length

[52 Ragtop]

If running the stock single M/C, you'll need to defeat the built in residual check valve. If running a dual M/C, you'll need to cut the linkage a little bit short, drill & tap the end and use a button head allen to "fine tune" the adjustmant.
That's what I did on the 62 Daytona ragtop I sold.

Jim

[struckinc]

car came stock with a dual m/c. we changed it to an aftermarket one. did not have built in residual valves. i checked it. thats why we added a 10# inline to the rears. almost seems like the throw is wrong on the linkage. i know someone has run into this problem before. wish we could find a rebuild kit for the stock cyl, so i can eliminate the possibility of having the wrong cyl. rebleeding it helped some. but still going to floor. if you pump the brakes it will hold. but if you let it sit for a few seconds it looses pressure. thats what made me think residual valve. but after installing it and it not changing anything, i am thinking the rod to m/c isnt long enough to get a full stroke and not building up enough pressure to hold

[StudeRich]

OR... the master Cyl. piston is not returning all the way, blocking the "Bleed Port" and not allowing the air to bleed out! [:0]

StudeRich

[struckinc]

what would cause it to not open all the way? wrong cylinder for rod length? or it needs to be taken off and completely re-bled?

[StudeRich]

quote:Originally posted by struckinc

what would cause it to not open all the way? wrong cylinder for rod length? or it needs to be taken off and completely re-bled?

Yes, since there were no Dual Master Cyl. for Disk brakes on Studebakers, there also was no push rod the correct length. An AMC, Dodge or whatever requires a special length push rod as Jim Turner explained.

StudeRich

[junior]

Another possibility is you have some low friction calipers that need a 'quick take-up' master cylinder. There was something on the forum last summer about this...only applies to gm intermediate body calipers such as Turner conversion uses. Junior



54 Champ C5 Hamilton car.