Diesel engines for two-wheel tractors and machinery

A diesel engine is the choice for machines that run for long hours under heavy load: heavy two-wheel tractors with a plough, trailer or mower, pumps and generators. This section lists single-cylinder, air-cooled WEIMA engines and one Grünwelt, from 6 to 15 HP. All have a 25 mm horizontal shaft that turns anticlockwise when viewed from the PTO side.

How to choose a diesel engine

• Power and displacement. The WM178F (296 cc, 6 HP) suits lighter two-wheel tractors. The WM186FBE (418 cc, 9 HP) is the typical engine for a machine working with a plough and trailer. The WM188FBE (456 cc, 12 HP), WM192FAE (498 cc, 14 HP) and WM195FE (531 cc, 15 HP) are for heavy machines and long shifts.
• Maximum vs rated power. The HP figure in the name is maximum power. For continuous work, rated power matters, e.g. 6.3 kW on the WM186FBE and 8.8 kW on the WM192FAE. Compare like with like against the old engine.
• Shaft type. 25 mm plain keyed or splined (the splined WM178F and the WM186FBE-W). Check what your machine's clutch or pulley needs.
• Air filter. Oil-bath versions cope well with dust during field work; paper filters are simpler to service, as you only swap the element. The price difference between versions is small.
• Starting. The WM178F is recoil start only; the other models have recoil and electric start. On a diesel of 9 HP or more, an electric starter makes cold mornings much easier.
• Weight. Diesels are heavy: from 33 kg (WM178F) to 57 kg (WM188FBE). Make sure the frame and mounts can take it.

Diesel engines in this section

Figures from the product pages. Fuel tank: 3.5 litres on the WM178F and 5.5 litres on larger models. Crankcase oil: 1.1 litres (WM178F) or 1.65 litres. Specific fuel consumption per the product pages: 285 g/kWh (WM178F, WM186FBE) and 281.5 g/kWh (WM195FE).

Operation and common mistakes

• Check and top up engine oil before the first start, and on oil-bath versions also the oil in the air filter.
• Use winter-grade diesel in cold weather. Summer diesel thickens in frost and makes starting hard.
• Do not leave a diesel idling for long periods without load; it runs better under normal load.
• Clean and replace a paper filter more often in dusty work; an oil-bath filter needs regular oil changes.

If your machine works occasionally and lightly, a petrol engine will be cheaper. Our guide petrol or diesel compares the two. Complete machines with a diesel are in diesel two-wheel tractors.

Frequently asked questions

Which diesel for a two-wheel tractor with a plough and trailer?
Most often 9 HP, such as the WEIMA WM186FBE. For heavier work and larger machines, 12–15 HP: WM188FBE, WM192FAE or WM195FE. Always compare with the power and shaft of the original engine.

Oil-bath or paper air filter?
Oil-bath copes better with heavy dust in the field. Paper is simpler: just replace the element. The WM186FBE, WM188FBE and WM192FAE come in both versions.

Can a diesel replace a petrol engine in my machine?
Only if the shaft, mounts and space in the frame match. A diesel is heavier and bulkier, so compare the dimensions on the product page (e.g. 440 × 417 × 495 mm for the WM186FBE).

How much fuel does it use?
The product pages give a specific consumption of about 285 g/kWh. Real consumption depends on load and the type of work.

What about warranty and delivery?
24-month warranty. Courier delivery across Poland, free from 999 zł; other EU countries on request. Returns within 14 days, return shipping paid by the buyer.