Hi Paul, my name is ***** ***** you for asking your question, I will try and help you out.
Sounds like you have two issues,, first is you have leak on suction side of fuel system (sucking air) before fuel pump,,its either a bad line or filter head,,second is fuel leak on pump.
The sucking air will cause filters to be half full and cause surging,,you can bypass filter head and see if it clears up, if it does filter head is bad,,if not do one fuel line at a time until its fixed.
Next I would order a rebuilt fuel pump that is cheapest way to go.
Click here for a rebuilt pump shop,,they do good work and probably have yours in stock so you can continue to use it.
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