Welcome to the group and don't worry about the English. We have a joke in this country.
What do you call someone who speaks three languages? Answer: trilingual
What do you call someone who speaks two languages? Answer: bilingual
What do you call someone who speaks one language? Answer: A native born American

I'm afraid I can't answer your question, because I've never experienced it. Maybe another pro will chime in here. You said you flushed the system. What are you using for fluid? Also get the #s off the pump and post in case someone installed the wrong pump from a wrecking yard. you may also have the wrong pulley.

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