Liqui Moly 21799 DEF Anti Crystal Additive Concentrate - 250ml

Ash-free combination of additives for the prevention of malfunctions in the SCR system of diesel engines. Reduces the formation of deposits in the AdBlue® tank and AdBlue® injection system. Guarantees extremely fine atomization of the urea solution by lowering the surface tension.

Optimizes the return flow of the AdBlue® into the system, thereby minimizing the risk of AdBlue® crystallization. For all SCR systems that are operated with 32.5 % urea solution (AdBlue®, DEF). When adding to the AdBlue® tank, should ideally be added after the filling process.

Applic­a­tion: Add 0.25 % to the AdBlue® solution (1:400). 25 ml is sufficient for 10 l of AdBlue®. 250 ml is sufficient for 100 l of AdBlue®.

2.5 l is sufficient for 1000 l of AdBlue®. For long-term application. Do not add to fuel!

When adding to the AdBlue® tank, should ideally be added after the filling process. Other inform­a­tion: Frost sensitive. Shake at room temperature to disperse deposits on bottom!

If diesel vehicles are equipped with an SCR system – i.e. with a system for selective catalytic reduction that reduces harmful nitrogen oxides using a urea solution (e.g. AdBlue®) – then a contribution to the environment has already been made.

But there is a small, often overlooked vulnerability: Crystal formation in the SCR system. This is exactly where DEF Anti Crystal Additive comes into play. In practice, deposits and crystal formation occur in the AdBlue® tank, in lines or injectors on many vehicles – especially when driving short distances or in winter.

This can have several unpleasant consequences: Blocked nozzles in the SCR system Error messages in the cockpit Increased consumption or even system failure In the worst case, a workshop visit with high repair costs These crystals are formed by the natural aging of AdBlue® or by residues – especially if the vehicle has been idle for long periods or if the dosing is incorrect. This can lead to the formation of additional poorly soluble substances such as biuret, cyanuric acid or ammelide - these are deposited in the SCR catalytic converter and impair its function. Even low-quality AdBlue® that does not comply with the ISO 22241 specification – for example with too many foreign substances such as magnesium, calcium or sodium due to unsuitable water – can lead to clogged injection nozzles and a faulty spray pattern, but above all to malfunctions and damage to the SCR catalytic converter.

This, in turn, significantly reduces the efficiency of the emission control system.