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DEF Crystal Clean™ Diesel DEF & SCR Emissions System Cleaner

Improves DEF Diesel Exhaust Fluid
Clears P20EE & Other OBD Codes
Restores SCR Selective Catalyst Reduction
Cleans DEF Injector, Sender, Guaranteed

Your best weapon against SCR white crystal buildup.

Are you tired of dealing with white crystals clogging your diesel vehicle’s Selective Catalytic Reduction (SCR) system? It’s a problem many diesel owners don’t address before it’s too late. Introducing Rislone DEF Crystal Clean™ – the ultimate solution to keep your diesel engine running smoothly and efficiently. Years of research has led us to this formulation, and there’s nothing else like it on the market.

See below for more details.

For: Diesel Exhaust Fluid

What it does:

CLEANS
Clear P20EE
DEF LIGHT
PREVENTATIVE MAINTENANCE
REPAIRS
SCR

Product Support:

PRODUCT SUPPORT

Product Details

Part Number: 4784

Dosage: For car or small SUV - 3 to 5 gallon tank use 1/2 bottle. For light truck to mid-size to large SUV - 5 to 9 gallon tank use the full bottle.

Size: 11.8 FL OZ (350 mL)

SDS / Tech Info:
4784 SDS	Open	Download
4784 PDS	Open	Download

Frequently Asked Questions

Additional Product Info

What does Rislone DEF Crystal Clean Diesel DEF & SCR Emissions System Cleaner do?

DEF CRYSTAL CLEAN™ Diesel DEF & SCR Emissions System Cleaner gives a cleaning effect on the entire SCR system by working to dissolve the white crystal deposits that form in the tank, pump, heater, sender, lines, injector, decomposition tube / reactor and mixer.

How much do I use?

P/N 4784 / 11.8-ounce bottle – One full bottle is used to treat light truck or mid-size to large SUV diesel vehicles with 5 to 9 gallon DEF tank. Car or Small SUV – 3 to 5 gallon DEF tank capacity use approximately ½ bottle. Medium and Heavy Duty Diesel Trucks— 10 to 20 gallon DEF tank capacity use 2 bottles.

How often should this be used?

Regular use every 5,000 miles not only keeps the system clean but works to prevent the white crystallization issues from returning.

Can a clogged supplemental catalyst reduction SCR system be cleaned?

Yes, many times it can, especially if you catch it early and it is not completely blocked.

What are the white deposits and where do they come from?

The white hard crystal deposits found in DEF fluid, or the SCR system are typically UREA that has crystallized. These crystals can block injectors and other parts of the SCR system.

Why does my engine need an SCR system?

The SCR system allows diesel engines to meet stricter emission regulations, while also maintaining performance and efficiency. Overall, the SCR system is an effective way to reduce NOx emissions from diesel engines, and it's a widely used technology in various industries such as automotive, marine, and power generation.

What is DEF?

Liquid urea and deionized water (32.5% urea and 67.5% water), also known as Diesel Exhaust Fluid (DEF) or AdBlue, which is injected into the hot exhaust stream of the diesel engine and is then pushed out the tailpipe.

What is AdBlue®?

AdBlue is a brand name used by license for many brands of diesel exhaust fluid around the world. DEF and AdBlue are one in the same.

What causes DEF fluid to go bad?

Evaporation & Leakage: If the DEF system has any air leaks, the DEF can escape and the water will evaporate, leaving behind crystallized urea. Age: Old DEF fluid in containers or in the system, especially if it has been exposed to sunlight. Overfilling: Overfilling the DEF tank can also lead to spills, which can then crystallize. Improper Handling: If DEF is not handled or stored properly, contamination can occur, which can also lead to crystallization. DEF should always be stored in a cool, dry, well-ventilated place away from direct sunlight. Poor Quality DEF: If the DEF used is not of good quality (meaning, it doesn't maintain the required ratio of deionized water to urea), it can lead to deposits.

Will this product harm the DEF, SCR or DPF system?

No, this will not harm your engine or any emissions components. Specifically designed and safe to use on vehicles which have DOC catalytic converters, DPF particulate filters, SCR selective catalytic reduction devices, ASC ammonia slip catalyst or DEF / AdBlue systems. Will not void manufacturer’s new vehicle warranty.

What are the most common diesel SCR check engine light CEL codes?

The most common codes for the SCR / DEF system are P20EE, P20EF, P20E8, P204F, P207F and P218F. These codes mean that the efficiency of the SCR is below its functional threshold, that NOx emissions are being exceeded, or there is an issue with DEF flow in the system.

What if I accidentally added DEF fluid or DEF Crystal Clean to my diesel fuel?

Accidently adding DEF fluid or DEF Crystal Clean to diesel fuel can cause serious engine damage. If the engine has not been started, the diesel fuel tank should be drained and cleaned. If the vehicle has been run, not only will the tank need to be cleaned, but the entire fuel system and then check the engine for damage.

Can I use DEF Crystal Clean if it has frozen?

Just like DEF fluid, DEF Crystal Clean can freeze. If it has frozen and the bottle is not broken, let thaw out, shake well, and then use as directed.

RISLONE® DEF CRYSTAL CLEAN™ Diesel DEF & SCR Emissions System Cleaner is a proprietary blend of DEF (Diesel Exhaust Fluid) / AdBlue® compatible cleaning agents and surfactant detergents specifically designed to be safe to use and work on SCR (Selective Catalyst Reduction) systems.

DEF Crystal Clean gives a cleaning effect on the entire SCR system by working to dissolve the white crystal deposits that form in the tank, pump, heater, sender, lines, injector, decomposition tube / reactor and mixer. These deposits can interfere with the normal operation of the SCR emissions system and engine, increasing fuel consumption and reducing engine power. This reduced power can lead to operating in limp mode where the vehicle will drive slowly, or become undrivable. This process restores function and with regular use maintains efficiency of the SCR.

Excellent for diesel vehicles driven regularly at slow speeds, low loads, short durations or make frequent stops as these are more prone to having the problem of crystallization deposit build up in the SCR system.
Regular use every 5,000 miles not only keeps the system clean, but works to prevent the white crystallization issues from returning.
Will not void manufacturer’s new vehicle warranty. Specifically designed and safe to use on vehicles which have DOC catalytic converters, DPF particulate filters, SCR selective catalytic reduction devices, ASC ammonia slip catalyst or DEF / AdBlue systems.
Works with all AdBlue, Aria 32 (Automotive Nitrogen Oxide Liquid Reducing Agent), AUS 32 (Aqueous Urea Solution), BlueHDi, BlueTEC®, Cummins®, DEF UREA, Duramax®, EcoDiesel®, PowerStroke®, TDI® Clean Diesel, and many more.

BENEFITS:

Avoid Costly DEF System Repairs
Improves Emission Component Life
Restores SCR Selective Catalyst Reduction Performance
Cleans Crystal Deposits, Guaranteed
Works with all UREA DEF / AdBlue Fluids
Restores Optimal DEF Injector Spray Pattern

DO NOT ADD TO DIESEL FUEL TANK

INSTRUCTIONS:

DEF Crystal Clean is specifically designed to only be installed in the Diesel Exhaust Fluid / AdBlue tank which usually has a blue cap. Do not add to the diesel fuel tank.
Light Truck or Mid-Size to Large SUV
5 to 9 gallon tank capacity install full bottle into DEF tank.
Car or Small SUV
3 to 5 gallon tank capacity use approximately 1/2 bottle.
Medium and Heavy Duty Diesel Trucks
10 to 20 gallon tank capacity use 2 bottles.
Pour DEF Crystal Clean into mostly full DEF tank or add and fill tank with diesel exhaust fluid. If light is still on after 250 miles or a few days of driving, second application may be required, or mechanical attention is needed.

NOTE:
Works with all approved diesel exhaust fluids. Some vehicles use a special filling adapter to install DEF / AdBlue into the tank. For those vehicles use special funnel or pour into mostly empty DEF / AdBlue bottle and install in system.

AdBlue® is a registered trademark of VDA Verband der Automobilindustrie

Available At:

Rislone products are available where auto parts are sold.

Direct

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