Symptoms of
Bad EGR Cooler for Heavy Duty Applications
Exhaust Gas Recirculation Coolers or EGR Coolers are
devices that cool the exhaust gases, and work in conjunction with the SCR to reduce
nitrogen oxide emissions (NOx) for heavy duty internal combustion engines. The
purpose of an EGR cooler is to facilitate the reduction of emissions and meet
current emissions standards set by the US Environmental Protection Agency. But
what happens if your EGR cooler begins to fail? What are some of the indicators
of a failing EGR cooler?
There are three 3 major symptoms of a leaking EGR cooler:
- White smoke. When an EGR
cooler starts to fail, it transfers coolant out of the EGR cooler
into your exhaust system. When this happens, the exhaust interacts with
that coolant and turns it into steam. This "white smoke" is released through
your exhaust system of your heavy-duty engine and is a sure sign of an EGR
failure.
- Missing
coolant from your D gas/overflow bottle. When your D gas/overflow
bottle is missing coolant, but you do not see any indication of an
external leak (i.e., dripping underneath the vehicle)-it is a strong
indication that your EGR cooler is leaking internally. As a result, it
drains the coolant in your exhaust system which
creates the possibility of engine overheating or in this case, "white
smoke."
- Slimy EGR valve. The most
efficient way to determine if your EGR is failing is to physically look at
it. If you remove the valve, which is located near the top of the engine
next to the oil filter, it should be full of a dry black charcoal carbon (soot)
which is from the exhaust system. If you have a failing EGR cooler, the
dry carbon would be replaced by a black slime - like substance. The is
caused by the hot coolant interacting with the hot exhaust and steam clogging
your EGR valve.
If you have ANY of these three symptoms, it is a strong
indicator that you have a failing EGR cooler.