The skin is wrinkled, cracked and leaking. The air leakage at the bottom of Ounai high-pressure pump is caused by the warping and cracking of the hose. You can loosen the fixing clip at the root and pull out the hose. Cut off the aging part with a paper cutter, reinstall the hose and fix the clamp. After a long time, the hose is getting shorter and shorter, so we can only replace it with a new one.