07-08-2012, 04:52 PM
Technician Turbocharger Guide for the 6.0L Power Stroke Engine
Tech Turbo Guide for the 6.0L Power Stroke Engine.pdf (Size: 916.98 KB / Downloads: 111)
TURBOCHARGER DESCRIPTION AND BASIC OPERATION
The turbocharger for the 6.0L Power Stroke engine is designed to improve throttle response by
providing boost control at low and high speeds.
The Variable Geometry Turbocharger (VGT) is electronically controlled by the vehicle’s PCM and
is hydraulically actuated using pressurized lube oil.
The VGT may also be referred to as Electronic Variable Response Turbocharger (EVRT).
The VGT uses a turbine wheel that is similar to a conventional turbocharger but the turbine
housing has changed.
The turbine housing contains vanes that control the effective
internal size of the housing. These vanes are hydraulically
actuated and electronically controlled.
When the vanes of the turbocharger are closed, the engine
will have a higher exhaust back pressure and create more
heat which will in turn warm the engine faster in cold ambient
conditions.
DIAGNOSTICS
When diagnosing a low boost concern, verify that there is no other concern that would cause low
power. Since boost is created by the heat of expansion, anything that can cause low power will
create low boost (ex. injectors, EGR, exhaust leaks, fuel pressure and quality, etc.). Before
replacing a turbo for low boost all other systems must be tested.
TURBOCHARGER NOISE
One common cause for turbo replacement is noise. A large percentage of the turbochargers
replaced for noise are not bad. Compared to the turbocharger on the 7.3L Power Stroke, the
VGT is louder, under some conditions, due to increased boost and compressor speed. This is
normal and should not be a cause for replacement.
Exhaust Leaks
Turbochargers have been replaced for noise concerns when the concern is exhaust
mis-alignment at the connections and bad or missing gaskets. There are four (4) locations near
the turbocharger that need to be inspected prior to replacing a turbocharger for a noise
complaint. One of these is located in the exhaust up pipe on the passenger side, there is a
flange that requires a metal gasket in the pipe just above the EGR cooler connection. There is
also a metal gasket at the EGR cooler that is held in place with a V-band clamp. If the gasket is
missing, damaged or the clamp misaligned, it could be misdiagnosed as a turbocharger failure.
Two other leak points are at the turbine inlet and outlet; misaligned clamps and pipes can cause
a noise concern. If the turbocharger itself is responsible for excessive noise, expect to find wheel
to housing rub and bearing failure.