There are several O-Rings.
fill your info at the bottom page www.starbaja.com
you have bad orings, wrong size, orings or you broke the other injectors or the their orings
it is orings of a family's name
They keep your shafts from getting loose, especially metal ones.
remove the gas lines on both ends, be careful not to drop your copper orings unless you are installing a new one. then remove the two bolts that have it mounted to the block. and install the new fuel filter and your done.
No, vinegar is acidic and may melt your orings, and wont clean the gun very much. Use paper towels to wipe off dirt and use any air-tool lubricant on the orings and prevent rust. Water will ruin electronics and may cause rust on certain parts.
if the main spring gets stretched or damaged. It should not need to be replaced regularly like orings.
That depends on WHICH o rings you're referring to, and whether you just want a price for parts, or for parts and labor.
cause you have rubber orings that go on both ends of the injectors you probably need to replace them
One of your o-rings is probably broken, or your valve is damaged. try taking it apart and replacing the orings.
You'll usually get better results if you simply buy some. If that's not an option, you can make O-rings by carefully cutting rubber string - or a too big o-ring - into the appropriate length and then glue it back together with Super Glue. The thickness has to be right though. Another option - even more dicey - is to take some vulcanizing tape and shape into a loop. Allow to cure, then install. Getting an even thickness is difficult.
Not aware that Hayward made motors. You need the pump seal, gaskets or orings and the tools to remove and reinstall the motor and the seal. The electrical connections and power need to be removed and or turned off at the circuit breaker.
remove cable from transmission with turning counter clockwise with pliers next reove bolt. pull gear assembly out replace outer seal and orings reinstall all parts avable at trans shop.