Testing for Leaks in a DPF System

October 2019

We have seen quite a few trucks in shops today that require more frequent than normal DPF service intervals. Not a great scenario for fleet or independent operators who rely on equipment uptime to generate revenue. So, what is a possible reason for this? It is usually caused by leaks in the intake system or exhaust system, located upstream of the DPF. But finding leaks can be a laborious task especially when many of them only occur when the engine is under a boost condition. Trying to generate boost on a running engine in the shop while spraying a soap solution in an effort to find the source of a leak just doesn’t work well and it can be dangerous.

The good news is there is an easier way to find where fluid may be seeping out from. Several companies make smoke machines, which have been commonly used in automotive applications for evaporative emissions diagnostics. However, there is a big difference in the machines used for diagnosing leaks on a turbocharged diesel engine. The smoke machine must have the ability to pressurize the entire intake and exhaust system at up to 20 psi while injecting a harmless vapor to quickly identify leaks. There are several well-known manufacturers making these machines today. If your shop is in the business of servicing DPF systems, an investment in this type of machine is money well spent.

Redline Detection Smoke Pro Total Tech Leak Detector

Redline Detection 95-0003B Smoke Pro Total Tech Leak Detector is a great option for techs servicing DPFs.

You can also help alleviate further issues by replacing used clamps on the intake, turbo and exhaust systems when they are serviced with NORMA brand OE quality heavy-duty clamps. We always recommend replacing the V-Band clamps and gaskets whenever a DPF aftertreatment system is serviced. Installing new clamps ensures that the components stay together and are leak free for their intended service duration. The gasket material, rust and debris can build up and become baked into the V part of the clamp which is why DPF clamps should always be replaced when removed. NORMA DPF kits make that an easy task as they include OE quality clamps and gaskets needed for the particular application.