Converting from single master cylinder to duel ?????

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604

604

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I want to put a duel reservoir master cylinder on my 65 Dart. But for now I want to leave it drum breaks. Just want the added safety of having two separate break systems. My questions are this.
1 What cylinder should I use?
2 Will I need a proportioning valve?
3 Dose any one make the hard lines to do this or will I need to make them.

Thanks for any input!!!!!
 
Good mprning 604, I have a 66 Valiant and going the same route.
I have learned allot, 1= no our drum brakes do not need a proportioning valve
and, well hear is the thread that I asked the same question just a couple days ago and there is a couple ways to do it and it is told by some great members how and why.
 
If it was me I would put in a proportioning valve from a newer 4 wheel drum brake car, I did with the 66.
A proportioning valve helps if one of the front or rear line ruptures you still have brakes. The same is true if you just run a line out of the master cylinder to the front and then a separate to the rear, but then you have to use brake line T's for the front lines
 
Thanks,
I read threw it and it is starting to make sense to me. I need a 1967 Drum break master cylinder.

Oh and I found this Distribution block at Year One. PN BTB2 It is a reproduction of the one for 65 and 66 cars with disk breaks and a duel master cylinder. So it splits the fluid front and rear. Should really save a lot of headaches!!!!!

http://www.yearone.com/serverfiles/fbshopmain2.asp?input=BTB2&SM=1&SC=1
 
You can get that stuff used much cheaper than Year One. I regularly sell the 67-72 proportioning valve for $25 cleaned and clear coated. (I'm out of them right now, but every parts car I get has one)
 
I have a question. Changing from a single to a double reservoir serve any significant purpose other than just you can do it. It seems most of these cars have been cruising the highways for 40 plus years and I haven`t heard of allot of brake failures. I`m not asking to be a smart ***, cause i just replaced my single one. maybe I screwed up????

Moe
 
duel (to fight to the death) > dual (two)....disk..disc...threw ...through....but we no (know) what you all are talkin' about.

The drum brakes on these 65s really suck. But at least the dual MC will be better. I put all 73-76 dart stuff on my 65. Best thing I ever did to upgrade to Disc...that and 14" radial tires...o and that anti-sway bar. It's almost like a GT car now. :) Well that weber upgrade was pretty good too and the remflex gasket. Then redoing the seats...and that CD player...
 
My only reason is safety. With the single cylinder if you blow a line you loose all brakes. With the duel in theory you only loose half you brakes. If you blow a front line you loose only your front brakes. If you blow a back line you loose only your back brakes. Were I live with windy twisty up and down roads it will help me sleep a little better at night having it!
 
do not loosen your brakes...always tighten...:) Mom...and losing your brakes is never a good thing.
 
I put a dual master cylinder (MC) in my 65 Dart, but mainly because I was redoing the brakes and wanted to allow for later front discs.

Re safety, I understand how a dual MC mitigates the risk of losing all brakes from a failed line. However, a dual MC doesn't prevent losing all brakes with no warning, in my experience. My 69 Dart had a dual cylinder (drum brakes), yet at a stoplight the pedal went to the floor. I had to pump the pedal to get brakes. I saw no warning light before. I recall the light on after, but maybe as I pulled the E-brake. It had a switch in the distribution block, which is supposed to turn on the light if front and rear pressures vary (assume), so either the switch/wiring was bad or both front and rear MC piston seals failed simultaneously (unlikely). Perhaps the former and I had been driving with no front or rear brakes for a long time until the 2nd seal failed.

My '65 Dart uses an MC from a 99 Breeze, however I don't have a similar "pressure imbalance" warning switch. Perhaps newer cars include that in the ABS block. I probably should have plumbed my setup with a distribution block from a later Dart, though I would need to mount it high since the rear proportioning valve follows and I don't want that down in the dirt. Another choice is to switch to the more expensive after-market proportioner that includes the switch. I'll put on my list. I am still better than my 65 Newport daily driver with its single MC. BTW, it also went to the floor at a stoplight, with a fairly new rebuilt MC. Took it apart and found a sharp port edge had cut the seal, perhaps from re-boring without filing the edge (can't trust rebuilders).

A question for experts. My new MC has a sensor under the reservoir to warn of low brake fluid (I assume). How does it works? It must be a magnetic signal since it slides in under the plastic reservoir without fluid contact. Inside the reservoir is a plastic part between the front and rear reservoir that can rock a bit. I assume it has a magnet or piece of steel. Is just a simple on/off mechanical switch or does it require high-end electronic condition to sense (AC excitation or such)?
 
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