Trx 400ex cam bearing

Was taking the head apart tonight to make sure I had put the cam bearing s in correctly,meaning didn’t know if I had put in the seal side facing outward wich I didn’t. My bad! And the left or back cam bearing does not have a seal on it anymore wich I don’t think it did when I first put it together. But anyway, it’s that seal absolutely important? Any help would be great!

Trx 400ex cam bearing

Was taking the head apart tonight to make sure I had put the cam bearing s in correctly,meaning didn’t know if I had put in the seal side facing outward wich I didn’t. My bad! And the left or back cam bearing does not have a seal on it anymore wich I don’t think it did when I first put it together. But anyway, it’s that seal absolutely important? Any help would be great!