oil leak from the recoil

i was doing an oil change tonight when i found oil driping down the rear cross member below the recoil. it took some doing but i got the recoil off and found it full of sand. this lead me to think that sand must have got into the seal behind the the starter ring, my big question is what does it take to get the bolt out of the center of the that ring. i tryed everything in my tool box, johnson bar to eletric impact. what do i try next? i have a ir231 air gun (but no compresor) is that to much? what is to much before i start hurting somthing inside? has anyone else had this problem? if so what is the fix so this will not happen again.