DPF and EGR Cooler Maintenance with Ultrasonic Cleaners

DPF and EGR Cooler Maintenance with Ultrasonic Cleaners

Diesel particulate and exhaust gas recirculation cooler filters lose efficiency over time. Indications include warning lights, increased fuel consumption, rough starts, stalling, and dark exhaust. Searching DPF and EGR cleaning yields many results on how owner-operators, fleet managers and maintenance shops deal with DPF and EGR cooler maintenance. Here is how an ultrasonic cleaner can extend DPF and EGR cooler filter service life.

DPF and EGR Filter Cleaning Challenges

Sponge-like structures, stacked filters and complex gas flow channels among other designs characterize the construction of DPF and EGR cooler configurations. 

The challenge: strongly adhering soot, carbon, ash, oily residues and other contaminants, especially within tightly confined spaces.

These contaminants are not easily removed by compressed air, fuel tank additives, aerosols, hot-water sprays and similar DPF and EGR maintenance techniques.

Moreover, high-pressure air and hot-water sprays can damage filters if not carefully applied.

Another point to keep in mind is proper disposal of the contaminants released by the cleaning technique employed.

In summary, no matter how hot the water, or compressed air pressure, or the composition of aerosol sprays and soaks, these techniques cannot match the thoroughness of an ultrasonic cleaner to maintain DPF and EGR coolers.

How Ultrasonic Cleaners Solve DPF and EGR Cooler Maintenance Challenges    

Ultrasonic cleaners are found in a wide range of applications including:

Ultrasonic cleaning proves successful in these and other applications because of its ability to access and remove contaminants from within, as we noted above, tightly confined spaces

 How Ultrasonic Cleaners Work

Cleaning action is produced by the unit’s ultrasonic generator, which is connected to ultrasonic transducers bonded to the bottom of the cleaning tank. 

When the unit is activated, transducers create countless microscopic vacuum bubbles in the cleaning solution. These bubbles implode when they come in contact with parts being cleaned including those in cracks, crevices and blind holes impossible to reach by manual scrubbing.  

The process is called cavitation action.

Cavitation action quickly strips away all contaminants in contact with the cleaning solution without damaging parts being cleaned.

If this suggests cleaning DP and EGR coolant filters in an ultrasonic bath, you are correct. The scrubbing, loosening and carrying away of contaminants within the most confined spaces of these filters can be accomplished by ultrasonic cavitation in an ultrasonic cleaner.

For more info on this please check our post how ultrasonic cleaners work.

Selecting Your Ultrasonic Cleaner for DPF and EGR Cooler Maintenance

Selecting DPF and EGR filter cleaners, as with other maintenance and repair equipment used by owner-operators, fleet managers and maintenance shops, calls for matching equipment to the tasks.

Fortunately, as noted by our links at the beginning of this post, an investment in an ultrasonic cleaner can be spread over several functions ranging from carburetors to engines, transmissions, fuel injectors, differential gears and on.

DPF and EGR filters come in a variety of sizes  and configurations. If you wish to add ultrasonic cleaning these units to the services you offer, please consider the size of the equipment you plan to service. So as to not take space here, please check our post on selecting an ultrasonic cleaner.

Prepping DP and EGR Filters for Ultrasonic Cleaning

Our suggestion here is similar to removing loose scraps from dishes, pots and pans before putting them in the dishwasher. (Or, for that matter, knocking loose mud off your or your kids’ trousers and other clothes before putting them in the clothes washer.)

The inlets of DP and EGR filters are first in line when it comes to trapping contaminants. Some but not all of this can be removed in advance by shaking, blowing or otherwise removing them before putting filters in the ultrasonic bath.

Prior removal of easily accessed contaminants, as with removing table scraps and loose mud, helps prolong the efficiency of the ultrasonic cleaning bath.

Positioning DP and EGR Filters for Ultrasonic Cleaning

Here your experience will be the ultimate guide. As noted in our post selecting an ultrasonic cleaner the entire unit must be completely immersed in the cleaning solution. Our suggestion is, if feasible, placing the inlet of a DPF filter down in the cleaning basket.

That way gravity will help in the removal of contaminants from the units.

For some configurations it is advisable during the cleaning cycle to reposition your DP or EGR filter to help ensure thorough cleaning action. 

DO NOT reach into the bath to do this. Remove the basket and, using gloves, reposition the parts as they will be hot.

If your DP and EGR filters contain spaces that can hold the cleaning solution, we also suggest, during repositioning, that you allow cleaning solution within these spaces to drain back into the tank. These spaces will refill when put back into the cleaning solution. 

When you are satisfied with the results, spray wash your cleaned DP and EGR filters with fresh water and allow them to dry before replacing in the vehicle. 

Selecting a Cleaning Solution for DP and EGR Filters

Over the years scientists have developed cleaning solution chemistries targeting specific cleaning challenges. Many of these are offered as biodegradable concentrates that help solve disposal concerns while offering economies to users.

A recommendation for cleaning digital particulate and exhaust gas recirculation cooler filters is Elma tec clean A4 diluted with water to make a 1 to 5% solution.

The usual procedure is to add an amount of water to your ultrasonic cleaner tank, then the correct percentage of Elma tec clean A4 for a full tank, then fill the tank allowing for displacement. 

Before cleaning, activate the degas or pulse function in your ultrasonic cleaner, or allow it to operate without a load in order to mix the solution and drive off trapped air that inhibits cavitation cleaning action.

Activate the unit’s heater to allow the solution to reach its manufacturer’s recommended temperature before initiating the cleaning process.

Maintain your Ultrasonic DP and EGR Filter Cleaning Solution

Contaminants removed during the ultrasonic DP and EGR cleaning cycle remain in the solution.  Cleaning efficiency diminishes over time. Some contaminants rise to the surface and can be skimmed off, others fall to the bottom and can cause tank failure if not removed. 

For more on this please scroll down to “Ultrasonic Cleaning Solution Maintenance” in our post More on Selecting Ultrasonic Cleaning Solutions

Need More Info on Cleaning DP and EGR Filters?

Deciding to employ an ultrasonic cleaner to maintain DP and EGR units calls for having the right information. Our shop may have other cleaning requirements that could be economically addressed by an ultrasonic cleaner. 

Let us help you make the right decision based on your unique requirements. Contact Tovatech’s ultrasonic cleaning professionals for unbiased recommendations on the correct answers to your cleaning challenges.

About Rachel Kohn

So how did an MIT Ph.D. end up selling refrigerators? When I figured out that a lot more scientists buy lab refrigerators than innovative leading-edge instruments. I hope that my many years of lab experience will help you find the right equipment for your work. Before co-founding Tovatech I worked in business development and project management at Smiths Detection, Photon-X, Cardinal Health, and Hoechst Celanese. And before that I spent 12 years as an R&D chemist at Hoechst Celanese and Aventis working on advanced drug delivery systems, polymer films and membranes, optical disks, and polysaccharides. Some day, eventually, I’ll make enough money to develop an innovative technology that will change the world. Read More