Anyone have one of these that works as designed? Mine worked perfectly the first time out of the box, but since I disassembled and cleaned it that first time, it has not worked at all. It will fill the hose, but will not fill the reservoir or inject through the needle. My guess is the check valve(s). There are two that have different length "stems" so not sure which is the correct one. I reassembled it the same way it came when I bought it, but it is not working now. Not sure if one of the check valves goes behind the grey plunger or not. I tried configuring every possible way and nothing worked. Here is how mine is currently put together, if someone could compare to theirs that's working. Thanks in advance.