Suzuki DF 90 Service Manual page 47

2-22 PERIODIC MAINTENANCE
4. Install oil pressure gauge in place of pressure switch hole.
09915-77311 : Oil pressure gauge
09915-78211 : Oil pressure gauge adapter
5. Attach engine tachometer to ignition coil high tension cord.
09900-26006 : Engine tachometer
6. Start engine and allow to warm up as follows :
Summer : 5 min. at 2000 r/min.
Winter : 10 min. at 2000 r/min.
7. After warming up, shift into forward gear and increase en-
gine speed to 3000 r/min. then compare pressure indicated
on gauge to specifications.
8. After testing, reinstall oil pressure switch. (See page 3-54)
9. Reinstall air duct.