The purpose of the stationary tests is to record key information on the engine, powertrain system, and electrical system that is monitored by the VIMS sensors. Stationary tests can be run on the vehicle near the truck shop; access to a haul road is not required. Information from the stationary tests can be compared to: 1. Expected normal values,
2. Earlier tests ran on the same machine, or 3. Tests that have been run on similar
machines.
When the information is compared, the overall condition of the machine systems can be determined without the need for more time consuming installation of service tools. The data logger and event recorder should be downloaded and cleared before beginning these tests. All 5 tests can be completed sequentially with the data logger turned on at the beginning of Test 2 and left on for the remaining tests. Estimated time to run all 5 tests is 0.5 hours if the machine is at operating temperature. If systems are not warmed, additional time will be required.
Test 1: Brake System Testing and
Operating Temperatures
The purpose of this test is to warm the machine to normal operating temperatures and to determine if secondary brake system is functional. The test is not intended to
measure maximum brake holding effort. Brake holding effort required to hold a machine at a specific engine rpm will vary from machine to machine due to differences in engine setting, power train efficiency, etc., and in brake holding capability.
Engine rpm at beginning of machine movement, with secondary brake applied, should be compared with the engine rpm the
specific machine was able to hold on a prior test.
1. Start the engine and allow air system pressure to build-up to maximum operating pressure.
2. Warm the engine and powertrain such that: a. Coolant outlet temperature is 175 - 195
°F.
b. Converter outlet oil temperature is 180- 195°F.
c. Transmission outlet temperature is 175- 195°F
3. Apply secondary brake.
4. Move the transmission shift lever to 1st gear range forward.
5. Release the parking brake.
6. Gradually accelerate the engine to 1200 rpm.
7. The machine should not move forward. 8. If the secondary brake does not function properly, have necessary repairs made. 9. Repeat this test with the service brakes. If
truck creeps forward at full engine speed, have necessary repairs made before continuing the stationary tests.
10. Set the parking brake and shut down the engine.
Test 2: Starting Test
The purpose of this test is to record engine cranking speed. If the truck has a prelube system installed, prelube oil pressure and system voltage drop during prelube will also be recorded.
Note: This test will deplete the air system, run only if an alternate air source is available for recharging the air system.
1. Set the ground level shut off in the "FUEL OFF" position.
2. Turn key switch to the on position, allow VIMS to go through self-test.
3. Verify that air pressure is 120 psi. If not, recharge the air system.
4. Turn on data logger.
5. Crank the engine until cranking stops
because of low air pressure. 6. Turn data logger off. 7. Recharge the air system.
8. Set the ground level shut off in the "RUN" position.
Test 3: Unloaded Engine Test
The purpose of this test is to record electrical system charging voltage and engine lubrication pressure as engine speed is increased. The time required to recharge the air system pressure is also recorded.
1. Turn key switch to the 'ON' position, allow VIMS to go through self diagnostic test. 2. Turn the data logger on.
3. Wait 10 seconds. 4. Start the engine.
5. Run engine at low idle for 10 seconds. 6. Leave transmission in neutral and
gradually increase engine speed from low idle to high idle in 15 seconds. Hold at high idle for 10 seconds.
7. Reduce engine speed to low idle. 8. With transmission still in neutral, snap
accelerate engine speed from low idle to high idle two times with 15 seconds between accelerations.
9. Reduce engine speed to low idle.
Test 4: Converter Stall Test
The purpose of this test is to record the engine response time against converter stall.Note: Do not apply the parking brake during the converter stall test. On VIMS equipped machines, applying the parking brake with the transmission in gear will cause a category 3 parking brake warning message to lock on the message center. This condition will prevent the serviceman from observing when the category 2 warning occurs from hot converter oil temperature during the stall test.
1. Position the machine on level ground at
least 50 meters from other machines, structures or people.
2. Put blocks behind the wheels to prevent movement of the machine.
3. Apply the service brake and retarder; shift the transmission to 1st gear forward and turn on the data logger.
4. Quickly accelerate the engine from low idle to maximum speed. Hold for 5 to 10 seconds at maximum engine speed. 5. Reduce engine speed to low idle. Hold for
60 seconds. 6. Repeat step 2. 7. Repeat step 3.
8. With transmission in 1st gear, accelerate the engine to maximum speed. Hold until the high torque converter oil temperature warning comes on (Level 2).
9. Reduce engine speed to low idle. 10. Shift transmission to neutral. 11. Turn data logger off.
12. Allow system to cool to normal ranges.
Test 5: Double Stall Test
The purpose of this test is to record the engine response time against converter stall and the implement hydraulic system pump.
Note: Do not apply the parking brake during the converter stall test. On VIMS equipped machines, applying the parking brake with the transmission in gear will cause a category 3 parking brake-warning message to lock on the message center. This condition will prevent the serviceman from observing when the category 2 warning occurs from hot converter oil temperature during the stall test. 1. Turn data logger on.
2. With transmission in neutral, accelerate engine to high idle.
3. Raise body.
4. Slow engine to low idle. 5. Lower body.
6. With engine still at low idle, raise body. 7. Lower the body.
8. With the service brakes applied, move body raise lever to "BED DOWN"
position, move the transmission shift lever to 1st gear forward range . 9. Accelerate engine to maximum speed
and hold until the high torque converter oil temperature warning comes on (Level 2).
10. Lower engine speed to low idle, shift transmission to "NEUTRAL", and move body raise lever to "FLOAT" position. Allow truck to cool for 60 seconds. 11. Repeat steps 8 and 9.
12. Repeat step 10. 13. Turn data logger off.