Hello. I have an fx impact. It was leaking so I used leak detector to find the leak. It was coming from the front gauge. I replaces with an normal black o rings. It stopped the leak but after 3 days it started to leak from the same gauge. So I checked and the o ring I just replaced was already crushed and damaged. I guess normal o rings will not work. I know Yong heng compressor don't use o rings to seal, they use white hard plastic type disc to make the seal. So for my impact gauge. Do I use o rings or white plastic disc to make the seal? It seem the rubber black o rings get crushed too easily by the pressure.