A mechanic poured in too much oil. Should the garage fix the issue caused by his mistake?

A mechanic said he poured in three litres of engine oil - which was too much and the car over revved. Now brakes won't work. He said he poured in too much as the oil measuring case was broken and not reading correctly. Should a mechanic know this before he pours in too much oil?
Yes, it is reasonable to expect the garage to show some level of competence. But accidents do happen from time to time (mechanics are human, after all). Either way, the garage is 100% liable for the damage because the car was in their care. They must fix the car free of charge or pay for another garage to put it right.
Answered by Dan Powell on

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