The EGR Cooler can be cleaned easily with Hydro-Zone’s EGR Cooler Cleaner II. Simply disconnect both ends of the EGR Cooler from your Peterbilt, Kenworth or Cummins diesel engine and attach our fittings onto the EGR Cooler ends. Add the manifold, hose, pump, bucket and EGR Cooler Cleaner II; then you can clean your EGR Cooler while still on the engine. Pour one-gallon of EGR Cooler Cleaner II into the bucket and add two gallons of water (hot water helps clean faster). Insert the pump into the bucket and make sure the hose connections are tight and the manifold valve for the cleaner is open. Turn the pump on and recirculate the EGR Cooler Cleaner II solution for one hour. Dispose of the EGR Cooler Cleaner II solution and add three gallons of fresh clean water into the bucket. Proceed with same procedure and turn on pump and recirculate the clean water through the EGR Cooler for 20 minutes. Dispose of the water solution. Connect an air line to the manifold and open air valve on the manifold. Allow the air to flow through the EGR Cooler for fifteen minutes to completely dry the EGR Cooler and EGR Cooler Valve.