Filter head with integral priming pump and valved bypass passage

A filter head including means for mounting a replaceable filter and separator element thereon, for removing impurities from liquid flowing therethrough, said filter head including priming means for filling said element with liquid and displacing air therefrom subsequent to replacement of said element, said element having a liquid in-flow area for accepting incoming liquid and air and a liquid out-flow are for delivering liquid and air that has been passed through the element, said filter head and priming means comprising:

• an inlet in fluid communication with a supply of liquid;
• a first fluid chamber in fluid communication with said inlet;
• a second chamber;
• pumping means in fluid connection with said second chamber for alternatively drawing a vacuum and applying fluid pressure in said second chamber under control of an operator;
• first fluid passage means for passing liquid and air form said first chamber to said second chamber;
• first check valve means in operative connection with said first fluid passage means for permitting flow of liquid and air though said first fluid passage means only from said first chamber to said second chamber;
• second fluid passage means for passing liquid and air form said second chamber to said in-flow area of said element;
• second check valve means in operative connection with said second fluid passage means for permitting flow of liquid and air through said second fluid passage means only from said second chamber to said liquid in-flow are of said element;
• and wherein an improvement comprises:
• third fluid passage means for passing liquid and air form said first chamber to said in-flow area of said element;
• and
• third check valve means inoperative connection with said third fluid passage means for permitting flow of liquid and air through said third fluid passage means only from said first chamber to said in-flow area of said element;
• said third check valve means being operative to automatically prevent flow through said third fluid passage means in response to said pumping means applying fluid pressure, and in response to a vacuum being drawn by said pumping means, to automatically enable flow through said third fluid passage means.