How to checking engine oil? - Dewalt DPD3100 Gas Pressure Washer

Guessing you may only have an 'oil filter screen".. Located behind hole cap at bottom of motor ref:
https://www.manualslib.com/manual/405363/Daelim-S1-Catalog.html?page=40&term=oil+filter&selected=1

Needs to be checked at the dipstick,
Under the bonnet on the engine!
The warning light, on most vehicles,
Only comes on when the oil is drastically low!!!!

These maintenance intervals come from the maintenance interval calculator
at www.autozone.com, using a starting point of 25,800 miles (43000 km), and
assuming 1000 miles (1666 km) driven per month, and "severe driving conditions," which
are actually normal usage characteristics, such as frequent short trips, urban driving, waiting in traffic, driving in hot weather, trips under 16 km in cold weather, etc.

STARTING MILEAGE: 25800 (43,000 Kilometers)
Item
Action
Service History

20000 miles or 32000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


21000 miles or 33600 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


24000 miles or 38400 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


25000 miles or 40000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


27000 miles or 43200 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


30000 miles or 48000 kilometers

Battery Check
Air Filter Element Check
Wheel Bearing Lubricate
Steering and Suspension Lubricate
Fuel Filter Replace
Oil Filter, Engine Replace
Engine Oil Replace
Fluid - A/T Replace
Cabin Air Filter Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Cooling System Inspect
Wheel Bearing Inspect
Ball Joint Inspect
Drive/Propeller Shaft Inspect
Exhaust System Inspect
Steering and Suspension Inspect
Heat Shield, Exhaust Inspect
Tires Rotate


33000 miles or 52800 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


35000 miles or 56000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


36000 miles or 57600 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


39000 miles or 62400 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


40000 miles or 64000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate



42000 miles or 67200 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


45000 miles or 72000 kilometers

Battery Check
Steering and Suspension Lubricate
Fuel Filter Replace
Oil Filter, Engine Replace
Engine Oil Replace
Cabin Air Filter Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Cooling System Inspect
Wheel Bearing Inspect
Ball Joint Inspect
Drive/Propeller Shaft Inspect
Steering and Suspension Inspect
Tires Rotate


48000 miles or 76800 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


50000 miles or 80000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


51000 miles or 81600 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


54000 miles or 86400 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


55000 miles or 88000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


57000 miles or 91200 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


60000 miles or 96000 kilometers

Battery Check
Air Filter Element Check
Wheel Bearing Lubricate
Steering and Suspension Lubricate
Fuel Filter Replace
Spark Plug Replace
Fluid Filter - A/T Replace
Oil Filter, Engine Replace
Engine Oil Replace
Fluid - A/T Replace
Cabin Air Filter Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Cooling System Inspect
Wheel Bearing Inspect
Ball Joint Inspect
Drive/Propeller Shaft Inspect
Exhaust System Inspect
Steering and Suspension Inspect
Heat Shield, Exhaust Inspect
Tires Rotate


63000 miles or 100800 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


65000 miles or 104000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


66000 miles or 105600 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


69000 miles or 110400 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


70000 miles or 112000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate


72000 miles or 115200 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


75000 miles or 120000 kilometers

Battery Check
Air Filter Element Check
Steering and Suspension Lubricate
Fuel Filter Replace
Oil Filter, Engine Replace
Engine Oil Replace
Cabin Air Filter Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Cooling System Inspect
Wheel Bearing Inspect
Ball Joint Inspect
Drive/Propeller Shaft Inspect
Steering and Suspension Inspect
Tires Rotate


78000 miles or 124800 kilometers

Steering and Suspension Lubricate
Oil Filter, Engine Replace
Engine Oil Replace


80000 miles or 128000 kilometers

Battery Check
Oil Filter, Engine Replace
Engine Oil Replace
Vehicle Inspect
Brakes and Traction Control Inspect
Tires Rotate



And you can continue the pattern from there...

OIL LEVEL CHECK Every time you stop for fuel, check the engine oil as follows:

1. Park the vehicle on level ground.
2. When checking the oil level it is best for the engine to be at operating temperature, although checking the oil immediately after a stopping will lead to a false reading. Wait a few minutes after turning off the engine to allow the oil to drain back into the crankcase.
3. Open the hood and inspect the level of the engine oil tank. The fluid level on the tank should read between FULL or F and LOW or L.
4. If the level is below the LOW or L line, remove the cap and add enough engine oil to reach the FULL or F line. Fig. 1: Fill the engine oil tank located under the hood first
   
5. Install the oil cap and hand tighten.
6. After filling the oil tank, remove the engine access hole cover on the drivers side. Fig. 2: Make sure the oil tank is to the F mark Fig. 3: The oil dipstick is located under the driver's side engine access hole cover Fig. 4: Place your finger through the hole and pull straight up to remove
   
7. Remove the engine oil dipstick and wipe it clean.
8. Reinsert the dipstick, push it in as far as it will go, the pull it out and look at the level on the end.
9. If necessary, insert more oil through the oil filler cap next to the dipstick, this will completely top off the system. Fig. 5: The oil dipstick has two markings for level check Fig. 6: To fill the crankcase, remove the engine oil filler cap

Oil Pressure Test Check for proper oil pressure at the sending unit passage with an externally mounted mechanical oil pressure gauge. A tachometer may also be needed, as some specifications may require running the engine at a specific RPM.

1. While the engine is cold, locate and remove the oil pressure sending unit.
2. Following the manufacturer's instructions, connect a mechanical oil pressure gauge and, if necessary, a tachometer to the engine.
3. Start the engine and allow it to idle.
4. Note and record the oil pressure reading when the engine is cold. The engine may need to run at a specified RPM, if so check the vehicle's specification.
5. Run the engine until normal operating temperature is reached.
6. Check the oil pressure reading again with the engine hot and record the value. Turn off the engine.

Compare the hot oil pressure reading to the specification. If the reading is low, check the cold pressure reading against the specification. If the cold pressure is well above the specification, and the hot reading was lower than the specification, the engine may have the wrong viscosity oil. Change the oil, making sure to use the proper grade and quantity, and then repeat the test.
Low oil pressure readings could be attributed to internal component wear, pump related problems, a low oil level, or oil viscosity that is too low. High oil pressure readings could be caused by an overfilled crankcase, too high of an oil viscosity or a faulty pressure relief valve.

To check engine oil level engine needs to be off, if check while engine running, oil will splash inside oil pan and all over your dip stick giving you bad reading, Check oil level with engine off and add to full mark on oil dip stick. Running engine with low oil will cause major damage to your engine. To check transmission level engine needs to be running at normal engine temp.

Engine oil: Engine turned off

Transmission oil, running warm in park.

Is it an oil pressure light or an oil change light (check the owners manual) If its an oil change light it may be time to change the oil. If its an oil pressure light you could have a short to ground in the wiring or at the oil pressure sender mounted on the engine. Also are you checking the engine oil with the engine running or off. The transmission is checked with the engine running, engine oil with engine off. If it is low on oil it will intermittently flash. Also when you check the oil wait five to ten minutes after the engine stops to let the oil settle before checking or you may get false readings.

The oil pressure warning light only comes on when oil pressure drops below 4psi at this moment there is no oil in the engine most often it does not get to this point because oil, water etc is checked every week. It could be your engine was using oil which would point to an engine fault.