The utility model discloses a multifunctional gear chamber. The multifunctional gear chamber is characterized by comprising a gear chamber body, a heat exchanger left supporting mounting seat, a tension wheel bearing structure, a heat exchanger right supporting mounting seat, a timing pointer mounting boss, a battery charger support, an injection pump gear cover locating pin hole, gear chamber double locating pin holes and a crank oil seal mounting seat, wherein the heat exchanger left supporting mounting seat is directly and integrally cast on the upper portion of the left end of the gear chamber body, the tension wheel bearing structure is integrated on the upper portion of the gear chamber body, the heat exchanger right supporting mounting seat is directly and integrally cast on the upper portion of the right end of the gear chamber body, the timing pointer mounting boss is arranged in the middle of the gear chamber body, the battery charger support is integrated at the right end of the gear chamber body, the injection pump gear cover locating pin hole is formed in the middle of the right side of the gear chamber body, the gear chamber double locating pin holes are formed in the lower portion of the right side of the gear chamber body, and the crank oil seal mounting seat is arranged on the lower side of the middle portion of the gear chamber body. The gear chamber is compact in structure, and realizes multi-functionalization and integration with other relevant parts.