Yamaha F4 (F4A / F4X) service guide
Oil, gear oil, spark plugs and the service schedule for the Yamaha F4 (F4A / F4X) (4 hp, four-stroke), from the factory service manual, plus how we service it in Hawaiʻi.
Models covered: F4AMH worldwide = F4MSHX / F4MLHX USA and Canada. Four-stroke single cylinder OHV, 112 cm³, tiller, recoil start, TCI. Model code 67D, starting serials S: 002408, L: 300739.
Quick answers
- How much oil does a Yamaha F4 take?
- 500 cm³ (16.9 US oz, 17.6 Imp oz).
- What engine oil does a Yamaha F4 use?
- 4-stroke engine oil, API SE, SF, SE-SF, SE-SF-CC or SG-CD, SAE 10W-30 or 10W-40.
- What gear oil does a Yamaha F4 use, and how much?
- GEAR CASE LUB (USA) or hypoid gear oil, SAE #90. Quantity: 100 cm³ (3.4 US oz, 3.5 Imp oz).
- What spark plug does a Yamaha F4 use?
- NGK B6HS / BR6HS. Gap: 0.6 to 0.7 mm (0.024 to 0.028 in).
- How often should a Yamaha F4 be serviced?
- The factory schedule lists: Initial 10 hours; 50 hours (3 months); Every 100 hours (6 months); Every 200 hours (1 year). 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 F4?
- The factory schedule says to inspect it at 100 hours and 200 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 F4?
- 1,500 ± 50 r/min (trolling speed 1,350 ± 50 r/min).
Maintenance specs
| Engine oil | 4-stroke engine oil, API SE, SF, SE-SF, SE-SF-CC or SG-CD, SAE 10W-30 or 10W-40 |
|---|---|
| Engine oil quantity | 500 cm³ (16.9 US oz, 17.6 Imp oz) |
| Engine oil drain plug | 18 N·m (1.8 kgf·m, 13 ft·lb), with washer and gasket |
| Gear oil | GEAR CASE LUB (USA) or hypoid gear oil, SAE #90 |
| Gear oil quantity | 100 cm³ (3.4 US oz, 3.5 Imp oz) |
| Lower unit holding pressure | 100 kPa (1.0 kg/cm², 14.2 psi) for ten seconds |
| Spark plug | NGK B6HS / BR6HS |
| Spark plug gap | 0.6 to 0.7 mm (0.024 to 0.028 in) |
| Spark plug torque | 25 N·m (2.5 kgf·m, 18 ft·lb) |
| Idle speed | 1,500 ± 50 r/min (trolling speed 1,350 ± 50 r/min) |
| Thermostat | Opens 58 to 62 °C (136.4 to 143.6 °F); fully open 70 °C (158 °F); lift 3 mm (0.12 in) |
| Anode bolt | 1st 3 N·m (0.3 kgf·m, 2.17 ft·lb), 2nd 8 N·m (0.8 kgf·m, 5.8 ft·lb) |
| Valve clearance, cold | Intake 0.10 ± 0.02 mm; exhaust 0.10 ± 0.02 mm (0.004 ± 0.0008 in); rocker arm locknut 10 N·m (1.0 kgf·m, 7.2 ft·lb) |
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
Replace: engine oil, oil drain plug gasket, gear case oil, gear case plug gaskets
Check: spark plugs, fuel filter
50 hours (3 months)
Replace: gear case plug gaskets, propeller cotter pin
Check: spark plugs, 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: spark plugs, fuel filter, water pump impeller, anodes
Every 200 hours (1 year)
Replace: engine oil, 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 F4X service manual, LIT-18616-01-79. Specs can change by model year and serial number, so always confirm your exact model from the serial tag on the clamp bracket.