What are the symptoms? What did you do to solve the problem on the left side? What did you do to rule out the master cylinder and caliper? Has any other brake-related work been done recently? If you had the left caliper off earlier, what was the condition of the mounting bolts and slides? Any sign of rust on the bolts?
This is the one that worries me the most; has any brake fluid been added to the reservoir and is there any chance it got contaminated with a petroleum product like engine oil, transmission fluid, or power steering fluid? A common symptom of that is the rubber bladder seal under the reservoir cap will be blown up and mushy. That will also occur to the rubber lip seals in the master cylinder. They will grow past the fluid return ports and block brake fluid from releasing back into the reservoir.
Once we look at the answers to these questions, we may need to discuss opening the hydraulic system at various places to see if and where brake fluid is being trapped.
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Monday, July 16th, 2018 AT 4:23 PM
