Brake upgrade in progress 63, 80

J

Jason63

New member
Gentlemen ,
I have a 1963 Scout 80 with both front and rear Dana 27's . I know that the front drums are 10 inch the wheel cylinders are 1 inch. I know the rear wheel cylinders are 7/8 bore but have not measured the drum yet. The old wheel cylinders both front and rear have wagner lockheed, ( lockeed ), stamped into them.
I don't plan on replacing the axels any time soon, I have a Dana 44 out of a 67, 800 that May go into the rear in the distant future, distant.I also have a power loc out of the front Dana 27 of the same 67 800 donor rig that I will put in the front Dana 27 in the 80
I will only do light wheeling, nothing radical.

My questions are,
I have already purchased a 1974 ***p cj5 master cylinder as my upgrade, I have read on here about proportioning valves can someone please explain a little more about this to me. I want to do this right.
As another note I am replacing the entire brake system, including, new hoses, wheel cylinders, lines, and master cylinder. I have completely tore down the front outer axels cleaned and painted , installed the new wheel cylinders and hoses so far.

All suggestions and criticism welcome
thank you, jason
 
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I apologize if this is clearly covered here before but was unsuccessful in locating a similar thread to what I'm dooin with the heep master cylinder
 
Is your upgrade to go to a dual circuit brake system? Did your Jeep m/c come from a disk or drum vehicle? Iirc drum brakes want a bit of residual pressure in the circuit and disks don't. Also you'll probably a switch for a brake failure light. There's usually no proportioning valve on drum brakes just a switch to show if one circuit fails.
 
Yes sir its a dual circut master cylinder. The new master cylinder is a "drum drum" master cylinder, I don't plan on upgrading to disc brakes. The reason I chose the *eep master was after a lot of reading and studying up it seemed to be the easiest to install with a small bit of file of the holes, the actuator rod would not need to be modified, and it gave me a safer brake system with the dual circuits.
I must of misunderstood the proportioning valve, I understood that it kept the risudal pressure so there was not as much travel for the brake shoes when you applie the brakes.
I will do a search on the site for proportioning valve so I can get a better understanding of its function.
I questioned the proportioning valve cause I have not heard, that I recall,that mentioned anywhere before, possibly because it doesn't apply to what I'm doing on my 80, and it seemed th be a logical thing to have.
The failure light is a good idea also, another thing I have not thought of

thank you, I appreciate the help
jason
 
One other reason I'm replacing the entire brake system is the original, existing was shot, wheel cylinders locked up with rust, hoses cracked, and line had rust in them. Although there isn't much that don't have rust in various formed and degrees of severity on this Scout:icon_mrgreen::eek6:
 
Ok,
found a thread labeled proportioning valve started by robg, the proportioning valve has no business in my system:gringrin:
what I need to check is if I have risidual pressure valves in my new master cylinder.

These can be bought right ? Maybe a silly question

I also read about making sure the pressures were equal by lockin them up on a gravel road.
The search is great !!
 
Yes search is your friend. The switch that triggers the brake failure looks sort of like a proportioning valve, but it is just a differential pressure switch. Probably the best one to get is for the same Jeep app as the m/c, that way if the residual pressure was maintained by the switch you're good. Residual pressure is usually maintained by the m/c though.
 
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