Thread: 1932 ford disc brakes locking up

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Originally Posted by Bob o

The weird part is it's worked fine for about 6 years without the spring. The only change is the master cylinder

Did you look at posts #13 & 14?

do you still have the first master cylinder so that you can check how far in the rod end seats?????????there have generally been 2 different lengths over the years and I think it came about because of power/manual brakes along about the time era of the separate front/rear brake systems------------

Originally Posted by rspears

Did you look at posts #13 & 14?

I just saw 13 and 14 it has only had dot three fluid in it and at this point I have bleed them several times so the fluid is crystal clear coming out. The rear brakes are not locking up only the fronts. The rubber brake lines were installed new in 2008 with the disc brake conversation. I thought about the lines but that also seems odd that both lines went out at the same time?

Get off the puter, put a spring on it and DTPOOI

Originally Posted by Bob o

I just saw 13 and 14 it has only had dot three fluid in it and at this point I have bleed them several times so the fluid is crystal clear coming out. The rear brakes are not locking up only the fronts. The rubber brake lines were installed new in 2008 with the disc brake conversation. I thought about the lines but that also seems odd that both lines went out at the same time?

If you think about it, it would make perfect sense that both (all three?) lines would go out at the same time, because whatever affected one line would affect the others as well. I'll admit the possibility small since the fluid is DOT 3. At this point I'd sacrifice a brake line and cut it in half to see if it has swollen, I had one last month that I couldn't stick a tig welding rod thru. You've changed all but the concrete the car is sitting on, not much else it can be. Just let us know, ok?

Originally Posted by DA34GUY

Get off the puter, put a spring on it and DTPOOI

Don, While I understand fully what you're saying, my under floor master (both clutch & brake) are working just fine without any springs pulling the pedals back. Given the leverage of the system and the placement of the fulcrum point relative to the pedals I can't see how gravity could "bounce" the system enough to offset the plunger or keep it from fully returning to the retracted point. I think this gremlin is somewhere else, especially considering that this car was driven for more than six years without problem until it leaked.

I have a busy week at work so hopefully I can get some work done on her this week end. I am thinking I should replace both brake lines if that doesn't get it then I will eliminate the residual pressure valve thanks for all the help at least now I have a direction to go. I will post up the resolution once I get it figured out...

Originally Posted by ojh

If you think about it, it would make perfect sense that both (all three?) lines would go out at the same time, because whatever affected one line would affect the others as well. I'll admit the possibility small since the fluid is DOT 3. At this point I'd sacrifice a brake line and cut it in half to see if it has swollen, I had one last month that I couldn't stick a tig welding rod thru. You've changed all but the concrete the car is sitting on, not much else it can be. Just let us know, ok?

Do what ojh says, and sacrifice one line to eliminate them from the equation. If you find it swollen and restricting change them all, but also consider that you may have a contaminated system, and if you do every rubber component is going to be suspect for failure. Is it possible that your Dad purged the system and used DOT 5 fluid when he did the earlier brake work?

I am pretty sure it was dot three because I found the receipt in the folder for dot 3 plus I found the bottle in the garage labeled hot rod he was pretty crazy about being organized. Either way it's worth checking the brake lines.

This is a bit embarrassing but I did say that I would report back. The master cylinder is good the pushrod slipped out of the pocket its supposed to set in and instead was pushing on the face of the piston keeping a constant pressure on the brakes. You can't see the pushrod without stuffing your head into the floor board. Not sure why it fell out. I popped it back in and everything is good if it falls out again I will weld a tab on the pedal assembly to prevent it.

Thanks for coming back with the answer. Like several said, it was acting like there was no pushrod freeplay, but for a different reason.

If it happened once, it will happen again.

Go ahead an put in the travel limit.

Or maybe lengthen your pushrod a tad, to eliminate some of the slack?

https://www.google.com/search?q=Mast...%3B2000%3B1081

Originally Posted by rspears

Or maybe lengthen your pushrod a tad, to eliminate some of the slack?

I can the push rod is adjustable. There is a tiny bit of play I will adjust the play out of the push rod it might have 1/16 or a bit more of slack right now