Well it leaks.
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2003 Volkswagen Golf Question: how to repair water housing and the o-ring?
Answer #1G. T. Service Center (4234 Answers) , Stephenville, TX - (254) 638-3236ProfessorG November 12, 2013, 09:01Master
Try www.alldatadiy.com for information.
Answer #2Greg's Orange Auto (14643 Answers) , Orange, CA - (714) 361-9386globalhelper November 12, 2013, 09:01Master
reseal and repl thermostat & housing