Questions and Answers
Astro Master Cylinder
Q. Hello, A 1989 Chevy Astro Van 4.3 Automatic 140,000 miles, ABS, P/S and A/C. With all lines unhooked and bleeder hoses installed on master cylinder when you press the brake pedal to bleed master cylinder the brake fluid instead of pumping it down it squirts it up into the reservoir. Large reservoir only. With lines hooked up we don't get any brake fluid to rear brakes. Help.
Thanks,
BillA. Fluid pumping back into the large reservoir is normal, that's why you have to pump slowly. If this is the original master cylinder and you are not getting any fluid through the line, you have a bad master cylinder. If this is a new or rebuilt master cylinder, then it is defective.
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