Yamaha F90 (F90D) service guide
Oil, gear oil, spark plugs and the service schedule for the Yamaha F90 (F90D) (90 hp, four-stroke), from the factory service manual, plus how we service it in Hawaiʻi.
Models covered: F90TR four-stroke, in-line 4 cylinder DOHC 16 valve, 1,596 cm³, fuel injected, L (20 in) and X (25 in) transom. Model code 61P, starting serial 1007790.
Quick answers
- How much oil does a Yamaha F90 take?
- 4.3 L (4.55 US qt, 3.78 Imp qt) without filter; 4.5 L (4.76 US qt, 3.96 Imp qt) with filter.
- What engine oil does a Yamaha F90 use?
- 4-stroke motor oil, API SE, SF, SG, SH or SJ, SAE 10W-30 or 10W-40.
- What gear oil does a Yamaha F90 use, and how much?
- Yamaha Gear Case Lube, SAE 90. Quantity: 670 cm³ (22.7 US oz, 23.6 Imp oz).
- What spark plug does a Yamaha F90 use?
- NGK LFR5A-11, qty 4. Gap: 1.0 to 1.1 mm (0.039 to 0.043 in).
- How often should a Yamaha F90 be serviced?
- The factory schedule lists: Initial 10 hours (1 month); Initial 50 hours (3 months); Every 100 hours (6 months); Every 200 hours (1 year); Every 500 hours (2.5 years); Every 1,000 hours (5 years). In Hawaiʻi's salt water we do a full yearly service every 200 hours or 1 year, whichever comes first, and a new engine needs its first (break-in) service.
- When should the water pump impeller be replaced on a Yamaha F90?
- The factory schedule says to inspect it at 200 hours and 1,000 hours. In Hawaiʻi's warm salt water we replace it every 200 hours or 1 year, whichever comes first, because a worn impeller is the most common cause of overheating.
- What is the idle speed of a Yamaha F90?
- 700 ± 50 r/min.
- What is the propeller nut torque on a Yamaha F90?
- 34 N·m (3.4 kgf·m, 25.1 ft·lb).
Maintenance specs
| Engine oil | 4-stroke motor oil, API SE, SF, SG, SH or SJ, SAE 10W-30 or 10W-40 |
|---|---|
| Engine oil quantity | 4.3 L (4.55 US qt, 3.78 Imp qt) without filter; 4.5 L (4.76 US qt, 3.96 Imp qt) with filter |
| Oil filter | 18 N·m (1.8 kgf·m, 13.3 ft·lb); oil filter joint 49 N·m (4.9 kgf·m, 36.1 ft·lb) |
| Engine oil drain bolt (M14) | 27 N·m (2.7 kgf·m, 20.0 ft·lb) |
| Gear oil | Yamaha Gear Case Lube, SAE 90 |
| Gear oil quantity | 670 cm³ (22.7 US oz, 23.6 Imp oz) |
| Gear oil drain and check screws | 9 N·m (0.9 kgf·m, 6.6 ft·lb) |
| Lower unit holding pressure | 100 kPa (1.0 kgf/cm², 14.5 psi), must hold at least 10 seconds (tester YB-35956-A) |
| Spark plug | NGK LFR5A-11, qty 4 |
| Spark plug gap | 1.0 to 1.1 mm (0.039 to 0.043 in) |
| Spark plug torque | 25 N·m (2.5 kgf·m, 18.4 ft·lb); spark plug wire cover screw 4 N·m (3.0 ft·lb) |
| Idle speed | 700 ± 50 r/min |
| Thermostat | Begins to open (0.05 mm) at 58 to 62 °C (136 to 144 °F); above 70 °C (158 °F) lift more than 4.3 mm (0.17 in) |
| Anode screw (M4) | 2 N·m (0.2 kgf·m, 1.5 ft·lb) |
| Propeller nut (M16) | 34 N·m (3.4 kgf·m, 25.1 ft·lb) |
| Power trim and tilt fluid | ATF Dexron II; fill to overflow at the filler hole, motor tilted up on the tilt stop lever. Reservoir cap 7 N·m (0.7 kgf·m, 5.2 ft·lb) |
| Valve clearance, cold | IN 0.20 ± 0.03 mm (0.008 ± 0.001 in); EX 0.34 ± 0.03 mm (0.013 ± 0.001 in) |
Service schedule
The factory maintenance intervals, with what is replaced and what is checked at each. Rows marked Hawaiʻi are our shop's yearly service for salt water use.
Initial 10 hours (1 month)
Replace: engine oil, oil drain plug gasket, gear case oil, gear case plug gaskets
Check: spark plugs, fuel filter
Initial 50 hours (3 months)
Replace: gear case plug gaskets, propeller cotter pin
Check: fuel filter, anodes
Every 100 hours (6 months)
Replace: engine oil, oil drain plug gasket, gear case oil, gear case plug gaskets, propeller cotter pin
Check: fuel filter, anodes
Every 200 hours (1 year)
Replace: engine oil, oil filter, oil drain plug gasket, gear case oil, gear case plug gaskets, propeller cotter pin, water pump impeller
Check: spark plugs, fuel filter, thermostat, anodes
Every 500 hours (2.5 years)
Replace: engine oil, oil drain plug gasket, gear case oil, gear case plug gaskets, propeller cotter pin, water pump impeller
Check: fuel filter, anodes
Every 1,000 hours (5 years)
Replace: engine oil, oil filter, oil drain plug gasket, gear case oil, gear case plug gaskets, propeller cotter pin, water pump impeller
Check: spark plugs, fuel filter, thermostat, anodes
We replace the water pump impeller at every service from 200 hours up, which can be sooner than the factory schedule, because of Hawaiʻi’s warm salt water.
Source: Yamaha F90D service manual, LIT-18616-02-86. Specs can change by model year and serial number, so always confirm your exact model from the serial tag on the clamp bracket.