Banks Power Cummins Motorhomes: (Diesel ’93 - 98 B5.9L & C8.3L) Power Systems- Stinger system 8.3L, 250-325-hp rated Class-A Pusher MH - Manual (Page 9)

CHECKING ENGINE PERFORMANCE
9 P.N. 96381
Go over the entire installation as a precautionary check to ensure that all
clamps are tight, wiring and hoses are properly routed, and connections
are tight. Start the engine and allow it to warm up. Drive the vehicle under
light load (normal around town driving) for 20 to 30 minutes, and listen
for any exhaust leaks or rattles, or intake boost leaks. Shut off the engine
and re-tighten all intercooler, intake and turbocharger boost clamps. If
your vehicle has an air compressor that feeds from the engine intake,
check these connections as well. These connections may have loosened
with time, and if leaking, will cause a drop in boost pressure with a loss in
performance. Check that clamps are properly positioned on hoses, and
periodically check tightness of hose clamps at regular maintenance
intervals, such as when the oil is changed. Engines with high mileage may
have broken or loose exhaust bolts, or blown gaskets between the cylinder
head and exhaust manifold. Repair any exhaust leaks as necessary.
Observe the operation of the boost and pyrometer gauges while driving
under varying conditions. Turbocharger boost pressure will increase as a
function of load and engine RPM, thus the engine will produce little boost
while cruising at light throttle, with maximum boost while climbing hills
heavily loaded during acceleration. Note the boost level seen during
hard acceleration with a given load. If performance seems to have
deteriorated sometime in the future, the maximum boost figures may be
compared to see if boost has dropped off. Lower boost may be caused
by turbo ducting leaks, a malfunctioning wastegate or fuel injection
pump, or a dirty air filter. Typical maximum boost pressure settings for the
Cummins diesel will vary considerably with different transmission models,
factory settings and altitude.
Use your pyrometer (exhaust gas temperature) gauge to monitor exhaust
gas temperature (EGT) in the engine. At idle, exhaust gas temperature
will be ver y low, perhaps only 300 degrees F. As the engine is
accelerated for higher speeds with greater loads, the EGT will rise. The
highest EGT will be seen under maximum load at full throttle, such as
climbing a steep grade with a heavily laden vehicle. Use caution if your
pyrometer reading approaches 1250 F, with 1300 F being the
ABSOLUTE MAXIMUM! Exceeding these figures for more than a
brief moment may cause engine damage.
If the vehicle reaches maximum EGT under these conditions, downshift the
vehicle to reduce load, or back off the throttle.