1961 cj5 brake master cylinder

Bryce Mcmahon

New member
I've had my Jeep sitting for a month now doing repairs and installing a new wire harness and so forth. It hasn't been driven or started. So I got everything done, and starts right up and I'm excited so I go to drive out and notice my brakes are not working ( they were working before I parked it) any ideas? The master cylinder is located on the frame on driver side door dose not look like there is a spot to put fluid into it. This is my first old car rebuild so learning as I go. So 1st question is there a way to fix this before i go trying to buy a new one, 2nd if I do have to buy a new one can I upgrade it to a better one or something? I'm lost I'm about to buy the whole brake system conversion kit but I dont want to shell out that much money yet lol any help would be a God send. Thank you.
 

There should be a round access cover with two screws on the floor board near the accelerator pedal. Your 1961 should have the floor board clutch and brake pedals as my 1973 has the suspended pedal set up but both will have that access plate . My master cylinder is firewall mounted but your chassis mounted master cylinder will be accessed from this round floor board plate. It should be right about where the removable center floor clutch access meets the toe board nearest to accelerator pedal. That should give you access to reach the plug on top the master to screw off the square drive . A six point socket won't fit so a twelve point socket will have to be trusted if no other tool will work in this confine . Please do use a good penetrating oil and give plenty time to soak in before attempting to remove it. Expect it to fight you but please use restraint as the cap may be aluminum . The master should be cast iron . I believe the original caps were cast iron but were found to freeze up so aluminum was a replacement , I believe.
 
as mentioned, there is a round cover on drivers side floor board, 1/2" socket. hopefully its just empty. You can switch to a hanging peddle set up, its best to use 71-74 peddles as they fit the contour of the floor better, 76-86 peddles will need a bend put in them and wrangler peddles will need shortened to 14" all work but the 71-74 need no mods. when you swap to hanging peddles you put your existing master on the firewall. Just did this over last winter.
 
if you go hanging peddles, great time to go hydraulic clutch as well. just need to make a bracket to mount the slave to, depending you may need to get a new throwout bearing but I didn't when it did mine.
 

I totally agree . A hydraulic slave is an asset on a jeep . Although I like mechanical linkage ( I'm just old school) , a hydraulic system prevents binding of the linkage when there is movement between the body and chassis. Whether it be a soft body mount or just body/chassis flex , the hydraulic system will not be affected like the mechanical linkage is. My 1980 CJ 5 has it and I just think it's a great idea for jeeps. Haven't researched myself if changing out throw out bearings or even a clutch fork swap is needed but when all is said and done , you'll love it. Even swapping out a replacement slave cylinder is cake . Something to think about .
 
The new clutch fork and throw out bearing come into play if the peddles and clutch fork your using don't have the correct ratio. If I remember correctly you need a 6.1 ratio at the clutch fork and a 5.1 at the peddle. its a quick formula to figure it out. I used the master and slave from a 81-85 4cyl cj, only the 4cyl got the hydraulic clutch from the factory.
 
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