Liqui Moly Pro-Line Engine Flush 500 ml — dissolves sludge & lacquer, safe for seals

Liqui Moly Pro-Line Engine Flush is a 500 ml oil-additive treatment designed to dissolve sludge, lacquer and deposits so you can safely flush them out before changing engine oil.

Before replacing engine oil, leftover deposits and contaminants can reduce oil performance and engine efficiency. Liqui Moly Pro-Line Engine Flush is formulated for use in all four-stroke gasoline and diesel engines to loosen and suspend residues so they drain away with the oil. It’s compatible with commercially available engine oils and safe for seals and catalytic converters when used as directed.

How do I use Pro-Line Engine Flush before an oil change?

Using this product is straightforward: add the 500 ml bottle to the existing engine oil, run the engine at idle for ten minutes to circulate the formulation, then drain the oil and replace the oil filter. Finally, refill with fresh engine oil to restore full lubrication properties.

• Add the entire 500 ml bottle to warm engine oil.
• Run the engine at idle for approx. 10 minutes to circulate and dissolve deposits.
• Drain oil, replace the oil filter, and refill with fresh oil.

What kinds of deposits and contaminants will it remove?

Pro-Line is designed to dissolve sludge, lacquer and other viscous deposits that build up inside the crankcase, oil galleries and sludge traps. It also helps isolate solid particles and liquid contaminants so they can be removed during the drain process.

• Dissolves sludge and lacquer from engine internals.
• Loosens varnish and sticky deposits on bearings and galleries.
• Suspends solid particles and separates liquid contaminants for easier draining.

Is Pro-Line compatible with my engine and seals?

Yes — the formula is neutral toward seals and common engine materials and is safe for catalytic converters. It’s suitable for both gasoline and diesel four-stroke engines and works alongside standard engine oils without adverse interactions when used according to instructions.

• Neutral to rubber seals and common engine materials.
• Compatible with catalytic converters and exhaust aftertreatment systems.
• Works with all commercially available engine oils.

How will this product affect engine performance and oil properties?

By removing internal deposits and contaminants, Pro-Line helps recover oil lubricating properties and can improve combustion efficiency and overall engine responsiveness. It’s a maintenance step to restore performance lost to internal build-up rather than a long-term additive for continuous use.

• Helps restore oil’s lubricating characteristics after deposits are removed.
• Can improve combustion process and engine responsiveness post-flush.
• Prevents corrosion of exposed metal surfaces during the cleaning cycle.

Who is this for: Liqui Moly Pro-Line Engine Flush 500 ml is intended for vehicle owners, mechanics and service shops preparing for an oil change who want a quick, effective way to clean internal oil passages and remove residues. It’s especially useful for vehicles showing signs of oil contamination, mild sludge formation or reduced oil performance, and for anyone wanting a thorough oil-change service using a product compatible with modern engines and exhaust systems.