Mitsubishi S3L & S4L maintenance: oil and filters
Mitsubishi S3L & S4L maintenance: oil, filters and V-belt
Proper maintenance of your Mitsubishi S3L or S4L starts with the right engine oil, clean filters, a correctly tensioned V-belt and healthy oil pressure. This article shows, per model, how much oil goes in, which oil type to use, which filters fit, what the oil pressure should be and how often you replace what — based on the values from the workshop manual.
Suitable for the entire series: Mitsubishi S3L, S3L2, S4L and S4L2 found in, among others, Vetus, Solé, Caterpillar, Mahindra, Solis, TYM and Farmtrac.
Mitsubishi S3L & S4L engine oil: type and quantity
The manual specifies engine oil of at least API CD class or higher. Choose the viscosity based on the outdoor temperature; a 15W-40 multigrade is a safe, year-round choice for most usage conditions in our climate. The oil quantity (full engine) differs per model:
| Model | Cylinders | Engine oil capacity |
|---|---|---|
| S3L | 3 | 3.7 liters |
| S3L2 | 3 | 4.2 liters |
| S4L | 4 | 5.4 liters |
| S4L2 | 4 | 6.0 liters |
These are fill quantities for the complete engine; always check with the dipstick after changing the oil, as the actual amount may vary slightly depending on installation and filter.
Mitsubishi S3L & S4L lubrication system and oil pressure
Lubrication runs via forced circulation with a trochoid/gear pump (capacity approximately 18 l/min). A relief valve limits the pressure and opens at 0.35 ± 0.05 MPa (3.6 ± 0.5 kgf/cm²). The oil pressure switch (warning light) closes at 0.05 ± 0.01 MPa. Oil pressure is a reliable indicator of your engine's health:
| RPM | Oil pressure |
|---|---|
| Rated speed | 0.29–0.39 MPa (3.0–4.0 kgf/cm²) |
| Low idle | minimum 0.098 MPa (1.0 kgf/cm²) |
If oil pressure remains low or the oil pressure light stays on during operation, stop immediately and find the cause (oil level, worn oil pump, relief valve or bearing clearance) before continuing to run the engine.
How to change the oil and oil filter
- Let the engine warm up briefly so the oil becomes thinner and drains more easily.
- Place a drain pan, loosen the drain plug and let the oil drain completely.
- Remove the old oil filter, lightly coat the new filter gasket with oil and tighten the filter hand-tight plus the additional turn indicated on the filter (reference value 10.8–12.7 N·m).
- Refit the drain plug (34.3–44.1 N·m) and fill with the correct amount of fresh oil.
- Start the engine, check for leaks and that the oil pressure light goes out, and recheck the level after a few minutes.
Mitsubishi S3L & S4L filters
Three filters need to be in good condition. The oil filter is a spin-on paper element. According to the manual, the air filter (paper element) should be cleaned every 100 operating hours and replaced every 500 hours. The fuel filter should be replaced every 500 hours, and sooner if water or sediment is present.
| Part | Application | SKU |
|---|---|---|
| Engine oil filter | S3L2 / S4L2 etc. | SKU-018 |
| Filter set (complete) | TYM T233–T293 — S3L/S3L2 | SKU-100130 |
| Filter set (complete) | TYM T300–T353 — S4L/S4L2 | SKU-100129 |
| Filter set (complete) | Mahindra Max 2615/2816 — S3L2 | SKU-100144 |
How to maintain the air filter
- Remove the paper element from the housing without damaging the filter.
- Gently tap out the dust or blow from the inside out with low-pressure compressed air; do not use water or oil on a paper element.
- Check the element against the light for tears or worn spots and replace it if in doubt.
- Clean every 100 operating hours and replace every 500 hours — sooner in dusty conditions. Avoid unnecessary disassembly, as each opening lets in dirt.
Mitsubishi S3L & S4L V-belt tensioning
The V-belt drives the alternator and the coolant pump. A belt that is too loose will cause the engine to overheat and the battery to drain; a belt that is too tight puts strain on the bearings. The correct tension: with a push force of approximately 98 N (10 kgf), the belt should deflect 10 to 12 mm measured between the crankshaft and alternator pulleys and between the crankshaft and fan pulleys. Also check for fraying and shiny spots and replace the belt if in doubt.
Checking Mitsubishi S3L & S4L valve clearance
Part of periodic maintenance: with the engine cold , the valve clearance should be 0.25 mm, both intake and exhaust. When adjusting, hold the adjusting screw in place while tightening the lock nut, and recheck the clearance after turning the engine a few revolutions.
Mitsubishi S3L & S4L maintenance schedule
The full hourly schedules belong to the operation/maintenance manual of your machine; the intervals below are a common guideline. The values for the air and fuel filter come from the workshop manual.
| Interval | Task |
|---|---|
| Daily / before use | Visually check oil level, coolant level, leaks, V-belt and air filter |
| Every 100 hours | Clean air filter; check V-belt tension (indicative: oil change) |
| Every 250 hours (indicative) | Change engine oil + oil filter; check valve clearance |
| Every 500 hours | Replace air filter and fuel filter |
| Annually (indicative) | Check/replace coolant, inspect hoses and battery |
Mitsubishi S3L & S4L maintenance torque values
| Part | N·m | kgf·m |
|---|---|---|
| Oil pan drain plug | 34.3–44.1 | 3.5–4.5 |
| Oil filter | 10.8–12.7 | 1.1–1.3 |
| Oil relief valve | 44.1–53.9 | 4.5–5.5 |
| Oil pressure switch | 7.85–11.8 | 0.8–1.2 |
| Oil strainer nut | 24.5–29.4 | 2.5–3.0 |
Maintenance parts in stock: engine oil filter (SKU-018), complete filter set S3L/S3L2 or filter set S4L/S4L2, and the V-belt (SKU-1240031). Low oil pressure due to a worn pump? We stock that too: engine oil pump S3L–S4L2 (SKU-21000).
Frequently asked questions
How much oil goes in a Mitsubishi S4L2?
Approximately 6.0 liters for the complete engine. An S4L takes 5.4 liters, an S3L2 4.2 liters and an S3L 3.7 liters. Always check the level with the dipstick afterwards.
What engine oil does the Mitsubishi S3L/S4L need?
At least API CD class or higher. For the Dutch climate, a 15W-40 is suitable in most cases; choose the viscosity based on the outdoor temperature.
What should the oil pressure be?
At rated speed 0.29–0.39 MPa (3.0–4.0 kgf/cm²) and at least 0.098 MPa (1.0 kgf/cm²) at low idle. If the pressure remains low, stop immediately and find the cause.
How often should the air filter be replaced?
According to the manual, clean the paper air filter every 100 operating hours and replace it every 500 hours — sooner in dusty conditions.
