Engine Flush vs Sludge Flush
“Simply put, engine flushing is ‘cleaning the inside of the engine.’ Just as you clean the body of your car by washing it, cleaning the inside of your engine will actually help keep it in good condition. Engine flushing involves using a special cleaning agent and flushing oil when changing the engine oil.”
For Honda S2000, the manufacturer’s maintenance schedule recommends to replace the engine oil and filter every 3,750 miles or 6 months if the car was driven in the severe condition. The definition of the severe driving condition is including;
Less than 5 miles per trip (in freezing weather, ;ess than 10 miles)
In extremely hot weather over 32°C
Extensively long adling or stop-and-go
Driving on winding roads
Because the definition was written 20 years ago, today’s normal driving condition does look like the severe condition in those days.
WHY NEED TO FLUSH ENGINE
By performing an engine flush, you can remove dirt from the engine, allowing the engine to run more smoothly like a new. Meaning you can expect effects such as improved acceleration and fuel efficiency and it will also lead to stable idling. In addition, you can expect the effect of making your engine last longer.
WHAT IS THE ENGINE FLUSH AGENT
Typically, removes deposits, residues, and carbon deposits from all 4-stroke gasoline and diesel engines. Flushes resin and asphalt deposits, which reduce the service life of metal surfaces and cause a thickening of the oil as well as sludge formation on engine parts, out of the oil circuit. Thoroughly cleans piston ring grooves and the upper area of the cylinder. Prevents rust formation on unprotected metal surfaces through acid combustion and condensation. Removes carbon deposits and paints which reduce the sealing effect of the piston rings. Restores the full engine performance and compression pressure, reduces friction, and improves emissions values. Ensures the restoration of oil lubrication properties. Ensures the perfect hydraulic function of oil-controlled systems such as VVT, VTEC, and similar. - from LIQUI MOLY
LIQUI MOLY 2427
PRO-LINE ENGINE FLUSH
Available from Amazon
HOW TO FLUSH ENGINE (for Liqui Moly Engine Flush)
Warm up the engine to normal operating temperature (i.e. 80°C or the cooling fan comes on).
Add the engine flush agent to the motor oil before the oil change.
Allow the engine to idle for 10-15 minutes.
Drain the oil.
If the drained oil is very dirty, fill new but economically less expensive engine oil and repeat from step 2 to step 4 again.
Drain the oil.
If you are satisfied that the drained oil is clean enough, change the oil filter.
Fill your proper engine oil.
INTERIM RESULT
We added one bottle of Liqui Moly Pro-Line Engine Flush agent to the 3,000-mile-old engine oil, idled the engine for 15 minutes, and drained it. An economically less expensive new oil (4.5L) was then added and drained straight away. This helps to understand how much dirty oil remains inside the engine. It looked relatively clean, but not perfectly shining clean. So the new (but contaminated) oil was returned to the engine to continue to test the Liqui Moly Sludge Flush agent. At this stage (before sludge flush), the engine compression pressure was slightly changed but we are not happy with the result yet.
WHAT DOES THE OIL SLUDGE FLUSH AGENT DO?
It removes black sludge and other contaminants and deposits inside the engine and increases the operational reliability of the engine and prevents lubrication deficiency. The agent gently cleans oil holes, oil screens, piston ring grooves and ducts and prevents engine damage. One 300 ml can is sufficient for engines with oil capacities of up to 5 liters. After adding the product, drive as usual for about 200 km, but avoid full-throttle operation. Then change the motor oil and oil filter.- from LIQUI MOLY
LIQUI MOLY OIL SLUDGE FLUSH 300ml
Available from Amazon
GB SKU 21103
D SKU 5200
AFTER THE 120 MILES TEST DRIVE
When finished the test drive, we found the drained oil got a further darker color. This means sludge was flushed during the 120-mile test run. But how much? So another set of new oil was used for draining the remainder of the dirt. After running the engine for 15 minutes, the new oil came out with no signs of dirt - it was shining gold. We are very satisfied with the result at this stage. It is time to fill the proper Honda 5W-40 oil and oil filters.
FINAL RESULT
As the last step of this experiment, an engine compression test was conducted. For Honda S2000 (AP1), 228 psi is the ideal compression. We observed that all four cylinders recorded the improvements towards the 228 psi target.
TEST 1 - 3,000 miles-old-oil
TEST 2 - After Engine Oil Flush
TEST 3 - After Oil Sludge Flush
