Iseki GEAS TG21-TG33 Engine Oil and Fluids
Changing the engine oil on your Iseki GEAS TG? Then you'll want to know exactly how many litres it takes and which type of oil to use. Below is an overview of all fluid capacities for the GEAS TG series, taken directly from the factory documentation.
Suitable for the entire series: TG21, TG23, TG25 (+TG25N), TG27, TG29 (+TG29F-16), TG31 and TG33.
Fluids and Capacities
| System | Capacity | Type |
|---|---|---|
| Fuel tank | 35.0 litres | Diesel oil JIS 2号/3号 (3号 for severe winter cold) |
| Radiator (cooling system) | 5.6 litres | Clean water or LLC antifreeze |
| Engine oil | 5.0 litres | Diesel engine oil (see viscosity below) |
| Transmission (mission case) — TG21 / TG23 (except -06) / TG25N | 22.0 litres | Universal tractor oil (UTTO type) |
| Transmission (mission case) — TG23-06 / TG25 (except N) / TG27-TG33 | 24.0 litres | Universal tractor oil (UTTO type) |
| Front axle (differential) — TG21 (except -06) / TG25N | 7.0 litres | Hypoid gear oil #80 |
| Front axle (differential) — other versions | 7.5 litres | Hypoid gear oil #80 |
| Lubrication points (tie rod ends, brake arm, centre pivot) | As needed | Lithium general-purpose grease |
Engine Oil: Viscosity and Changing
A 15W-40 diesel engine oil (API SG/CD or higher) is a great and widely available choice for the E3CE, E3CF and E3CD engines in this series. Always check the level between the upper and lower marks on the dipstick — never fill above the upper mark. When changing the oil: drain it via the two drain plugs, refill through the filler opening to the correct level, let the engine run for about 5 minutes, and then check the level again.
Every time you change the oil, also replace the oil filter: unscrew it with a filter wrench, apply a thin layer of fresh oil to the rubber seal of the new filter, and tighten it by hand — about 2/3 of a turn after the seal makes contact with the engine block. Overtightening with tools will damage the seal.
Transmission and Front Axle Oil
Pay close attention to your exact version when it comes to transmission oil: the TG21, TG23 (non-06) and TG25N use 22.0 litres, while the other versions (TG23-06, TG25 non-N, and the entire TG27-TG33 range) use 24.0 litres. When changing the transmission oil, always remember the hydraulic system's bleed plug: after refilling, let the engine run for about 5 seconds and then switch it off again before tightening the bleed plug — otherwise you risk the gear pump seizing due to air in the system.
Coolant
At temperatures below 0°C, always use antifreeze (LLC) instead of plain water — this prevents frost damage to the block. Flush the cooling system periodically and keep a close eye on the water level: insufficient coolant is the most common cause of a blown head gasket or cracked cylinder head in this engine family.
