Chassis Dynamometer Testing - Detroit Diesel MBE 900 Technician Manual

INTRODUCTION
PRESSURIZED AIR AND FLYING PARTICLES
To avoid injury to eye or face, wear a face shield or goggles
when conducting a pressure test.
Use proper tools for pressure testing Charge Air Cooler system.
Tools not rated for adequate pressure or with improper connections
can break free and cause engine damage.
Pressure check the air inlet system with 172 kPa (25 psi) regulated shop air. Use liquid
soap to identify any leaks. Pressure check from turbo discharge connection to cylinder
head noting and correcting leaks at hose clamps and on hoses or air-to-air charge cooler.
NOTE:
If air-to-air charge cooler is leaking from this initial check, pressure check it separately
at 207 kPa (30 psi). Pressure must not lose more than 35 kPa (5 psi) in 15 seconds
with shop air off.
Verify turbocharger is functioning properly.
1.3.4

CHASSIS DYNAMOMETER TESTING

Run the vehicle on a chassis dynamometer and look at the following:
To avoid injury or injury to bystanders from fumes, engine or
vehicle fuel system service operations should be performed
in a well ventilated area.
NOTE:
Ram air fans in front of vehicles and room ventilation are required.
Record the following data at 1650, 1500, and 1350 rpm, (Direct drive):
Wheel horsepower with vehicle fan on (Wheel horsepower above 80 % of rated power
at the wheels is acceptable. Refer to performance curve.)
Intake Manifold Pressure (If reading is erratic, take a snapshot.)
1-6
NOTICE:
EXHAUST FUMES
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION
PRELIMINARY
All information subject to change without notice. (Rev. 5/05)