Hard brake pedal manual brakes.

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1974chevy

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350 sbc
I am new here so bare with me. I recently inherited my grandfathers 74 c10. I am trying to diagnose the brake system. The truck has manual brakes with disk in front and drum in rear. The truck has a hard brake pedal. I have bleed the rear brakes, but their is no fluid going to the front calipers. I have broke the lines loose at the proportional valve and fluid comes out. I am out of ideals. Thank you for your time.
 

Dmack

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Do the front wheels turn? If the brakes are locked up, it's not u common for the flex lines running from the frame to the calipers to leak internally, between the layers of rubber. It results in the the line working like a check valve, allowing it to pressurize, but not release immediately. They may release slowly over time.

If they aren't locked up, it could be frozen calipers, Plugged lines, bad master...
 

Frankenchevy

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If fluid comes out of the individual ports for front lines on the PV, you may have clogged lines. Try loosening the line at the caliper to see if you get fluid. If you do, the calipers may be stuck.
 

PrairieDrifter

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Check the lines as said above, usually a hard pedal or no pedal is caused by a bad master cylinder.
 

roundhouse

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Could be a bad master or more likely frozen calipers and bad flex lines

You can loosen the bleeder screw on the calipers and see if you are squirting fluid when you step on the pedal
And you can also open the bleeder screws and use a large screwdriver between the rotor and the pad to push back the caliper piston

With the screws open it should be easy if the caliper is not frozen with rust inside

When you buy new ones
Try to order some that are new, made in North America , not rebuilt , and not made in China .
It will take several phone calls
It is now nearly impossible to find auto parts that are not made in China garbage


Replace the flex line on the rear axle too , finding flex lines that are not made in China will be the most difficult non Chinese part to find

And keep your original master and calipers for a while , maybe you can find a place to rebuild them
Or use them to make sure the replacements you order are the proper ones
Don’t turn your originals in for the core refund until you know for sure you have the correct replacements
 

1974chevy

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350 sbc
Thank you all for your help. I took line loose at the calipers and no fluid comes out. The calipers are not froze and easily move in when pressed on. I will order new flex lines and post back when I get them on. Thanks again.
 

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