To improve engine performance even in case that the structure of exhaust system is simplified by providing four cylinders of internal combustion engine with two exhaust gas passages and sharing one exhaust gas passage within every two cylinders.
An exhaust port 35 communicating each combustion chamber 32 of a first to a fourth cylinder 20 to 23 to outside of a cylinder head 27 is formed in the cylinder head 27. A first and a second exhaust gas passage 39, 40 extending toward a vertical direction are formed in a cylinder block 25. Downstream end of each exhaust port 35 of two cylinders 20, 23 out of the first to the fourth cylinder 20 to 23 is connected to the first exhaust gas passage 39 respectively. Each exhaust port 35 of other two cylinders 21, 22 is connected to the second exhaust passage 40 respectively. A connecting part 46 of each exhaust port 35 of the first and the second exhaust gas passage 39, 40 is positioned at roughly same place in a lateral direction in a view along one direction.
| JP2667175 | [Title of Invention] Outboard motor |
| JP2001098950 | OUTBOARD ENGINE |
OCHIAI KATSUMI
TAKAHASHI MASAAKI
| JP2001027151A | 2001-01-30 | |||
| JPS62135844U | 1987-08-26 | |||
| JPH10231734A | 1998-09-02 |
Next Patent: COMPOSITION FOR SLIDING MEMBER