I rebuilt my master cylinder (39 ford) about a year ago and put it on my 35-40 frame. Worked fine, never leaked. I took it off and put it straight on to my AV8 setup, filled it and blead the lines. I noticed some fluid coming out from around where the brake rod goes into the MC....never thought too much about it. I come out into the garage the next day and it there was a pool running all the way to the floor drain. I took it apart and everything looks good. However, I'm not sure I have all the components in order. I have the diagram from the old Ford manuals but there were come pcs in my kit that wasn't in the Ford diagram and visa versa. Any ideas? I'm going to clean up another old MC that I have and put the pcs in it and try it. I just thought I'd see if anyone has seen something similar.
I wouldn't use parts from a leaking master in another cylinder-I'd buy another kit and rebuild the replacement before using it...
The 39 truck was leaking same place after all 4 corners and the lines made up. Supposedly another buddy "went through it". turned out the parts were new and it was never honed. Cup was damaged by the abrasion, so I had a good used one I put in and it held. I would check the bore and the cup surface real close. Also a lot of the wheel cylinders acted up because I stored them with fluid in them. Got rusty and leaked just from sitting around. Mac Van-Pelt's drawings were the only online reference I know of, off the Fordbarn's links page. He's like almost your neighbor?
The googlie nut on the axle screw needs a new washer I would get a new kit, run a nice clean hone..and give it a shot again. If your rebuilt kit was NOS...the age, dry rubber might have caused the shortness of life. Just a thought.
Personally I'd buy a new one (M/cyl). A new brand name m/cyl from a parts store isn't that much. Just avoiding the agravation makes the small added expense worth it to me.
anyone know the sequence of components? i have the old diagrams but they don't look the same... EDIt: there is a thick flat washer that goes in before the retaining ring...not in pics...i have one though edit 2: i think he added the cut away view since i rebuilt this about a year ago...pic added
Seems like whatever is going on, the secondary cup has to be bad or at least unhappy with the surface it is trying to seal against!
Can't count on kits being right. There is only 1 donut seal thing used. stacked up, the donut first, the check valve with the dome up to fit the big end of the spring. My kit didn't come with a thin br*** washer, so It's not there.
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