I have had an issue with loosing prime from time to time. While using the hand primer the other day I noticed diesel and air bubbles coming from under the pump assembly between the filter housing and pump. After disassembly I see that all I need is the one o-ring that seals the plunger to the housing. I called gm to get the o-ring. They say oh no sir no part number on that you must buy the assembly for 668.00 I laughed at the man. I will not. I need a .30 cent o-ring. Has anyone had this issue? Any suggestions on where I could get one? Hell any suggestions at all? Thanks.