Author Topic: Brakes won't bleed  (Read 1911 times)

SgtKish

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Brakes won't bleed
« on: July 27, 2025, 01:05:13 AM »
OK, I know this sounds ridiculous, but I am stumped here. I rebuilt the Master cylinder, new lines, hydrovac,  wheel cylinders, and rubber lines. I filled the MC and I can't get the fluid to push through the lines. It will show a squirt of fluid when looking in the reservoir each time I pump the brake. It will shoot a stream from front to the back of the MC. Not sure if that helps at all.

    When I open the lines on each wheel to bleed. I have tried 4 different ways of bleeding each wheel. I can't get any fluid, even using a strong vacuum machine. So I took the MC off to bench test it by running a clear line from the bottom back into the top. It does push and pull the fluid at that bottom hole, but it only goes about halfway up the line. I have to work that thing pretty fast in and out to get an air bubble mixture of fluid back into the reservoir.  So it acts like it works, but I feel like slightly pushing in on it should squirt a nice airless line of fluid back into the reservoir.

    Does anyone know if this is normal, or should it be stronger and easier to push fluid back in it while testing? Any ideas on why even with a strong vacuum. That i cant pull any fluid to any wheel? I never had this problem on the last track, and I cant remember what I did to bleed her. I dont think it was anything different or difficult though. Do I have something in backwards maybe? Does the lines have to be full before the pedal will work for bleeding? What am I doing wrong here guys?

Thanks for any help, I really need her to move soon. Well and stop too..lol.

Mark

emptyhead

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Re: Brakes won't bleed
« Reply #1 on: July 27, 2025, 06:11:34 AM »
One thing to check is to make sure your pedal is properly adjusted. Mine wasn’t and the brakes dragged badly until I adjusted the pedal. Good luck.

Torque

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Re: Brakes won't bleed
« Reply #2 on: July 27, 2025, 11:44:25 AM »
I would take it apart, I think you have something assembled wrong.

brit plumber

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Re: Brakes won't bleed
« Reply #3 on: July 28, 2025, 02:44:43 PM »
Has the MC been sleeved?
1942 VEP GPW

SgtKish

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Re: Brakes won't bleed
« Reply #4 on: July 28, 2025, 10:17:49 PM »
No, I haven't got a measurement on it. Is there a max number for the bore? If the bore is too worn out, will it do that? Half way push the fluid, not as strong through the line?

SgtKish

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Re: Brakes won't bleed
« Reply #5 on: August 01, 2025, 02:18:59 AM »
Thought I would explain my stupid mistake. Just incase someone does the same thing down the road. I did put the valves in backwards. The valve that goes in first at the end of the spring. There are 4 metal tabs that the spring sits in, but on the other side. There is a round rubber end that sits inside the spring very well...haha. Its pretty obvious in the manual, which i did use while rebuilding it. So dont ask how I still managed to flip it the wrong way. Anyway, I guess the point here is. Pay closer attention.  Then triple check your work, or you're going to pay in extra work and wasted time. Thanks guys for the intel, and responding back to me. She's working good now.

Monkeypirate

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Re: Brakes won't bleed
« Reply #6 on: August 01, 2025, 07:22:55 AM »
Its always a nice feeling to fix a problem after your done kicking your self! I will take a minor mistake in assembly over a worn or damaged part any day.