Faulty master cylinder symptoms?

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PareosWC
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Faulty master cylinder symptoms?

Post by PareosWC »

We all like to give the Chinese heck over the slope top MC problems, but what exactly are the symptoms of a faulty one?

I have new lines, MC, brake shoes, and just had the drums turned.

I get a solid line of fluid at the front 2 hoses, but the rears are half air, half fluid when my Son pushes on the pedal. An hour of bleeding, and the brakes are getting better, but still only at about half pedal.

Is their a chance that the MC is not pushing enough psi to clear those rear lines? Who here gets brakes almost as soon as they press the pedal??
Ray Edsall
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Re: Faulty master cylinder symptoms?

Post by Ray Edsall »

G,Day Pareos . Did you bleed the longest , rear first ,then the next longest rear , then the next longest front , and finally the shortest brake line ? This is the way to correctly bleed brake lines . My wc53 stops when you take your foot of the accelerator ' Rolling resistance of a slug .O well it never gets much over 45 mph .As for the Chinese master cylinder , good luck . Cheeps Ray
Kaegi
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Re: Faulty master cylinder symptoms?

Post by Kaegi »

is there any leaks at the union on top of rear axl where hose and 2 lines meet? are rear wheel cylinders aessmbled correctly?
PareosWC
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Re: Faulty master cylinder symptoms?

Post by PareosWC »

As a deserved update-

I had the front drums turned a hair. As of now, I don't have any obvious leaks, and I have a firm pedal at about 50% pedal distance. The brakes are solid, and not spongy.

Out of all of the various methods of bleeding, I feel that the 'hose into a jar of fluid' worked best. My Mityvac was a miserable mess, my Son was pushing the pedal for days, and I was dribbling more fluid on the ground than in the circuit. Lastly, the adjustments of the major/minor are crucial more than originally thought..

It needs another full round of bleeding and inspection, but I needed a break before throwing a match to it.. :lol:
Kaegi
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Re: Faulty master cylinder symptoms?

Post by Kaegi »

the adjustment is a big deal on these systems. these are non servo brakes. that means they are fixed anchor and adjustment needs to be very precise for good pedal and braking. Later drum brakes are servo type where the shoes essentially float in the drum and adjustment is easier and not as critical. our non servo are a superior set up for off road. when they get wet you still have brakes unlike the later servo type.
PareosWC
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Re: Faulty master cylinder symptoms?

Post by PareosWC »

Thanks for the clarification- I had no idea.