Certain Pavers May Turn Slightly When Starting And Stopping Caterpillar

Certain Pavers May Turn Slightly When Starting And Stopping

Usage:

ASPHALT PAVERSAP-1055B (ABB, 8BM),
BG-2455C (ACM, 6TN) ASPHALT PAVERS

Problem:

The machine may "index" or turn slightly when starting and stopping. This condition can be caused if the left and right propel pumps neutral and initial current adjustments are not closely matched.

Solution:

The pump matching adjustment procedure is performed as follows:

1. Install two "Fluke" or equivalent multimeters to monitor the left and right propel pump forward EDC coil current. The left multimeter is to be connected in series with the left pump forward coil pin #10 at the propel MPC-10 controller 40 pin connector. This can be accomplished by disconnecting the wire at pin #10 and installing a test wire in pin #10 that leads to one side of the multimeter and connecting the other side of the meter to the wire removed from pin #10 thus putting the meter in series with the left forward EDC coil. The right forward EDC coil current is to be monitored at the same time using pin #33 at the propel MPC-10 connector by putting the meter in series with the right forward EDC coil similar to the procedure described for the left.

2. Check the propel software version by viewing the MPC-10 display window while turning the key to the ON position, as the MPC-10 powers up "888" will flash once and then a three digit software I.D. number is flashed. Make note of this number.

3. Start the engine, put the propel MPC-10 into calibrate mode "2", the MPC-10 will automatically increment to "c12", set the engine to high idle, propel lever forward, propel speed dial at 50%, pave range, parking brake released. After the propel status light is flashing, record the current values displayed on the multimeters for the left and right forward EDC coils, while the machine is in auto-calibration mode and light flashing.

4. Machines that have version "220" propel software installed should display 16-21 milliamps for the left and right forward initial calibration current. Machines that have version "301" propel software or higher should first ramp up to 9-13 milliamps for the left and right forward initial calibration current, then drop off to zero next it will ramp up again this time to approximately 16-21 milliamps and hold while the propel status light flashes.

5. If the initial calibration current does not fall within the above described ranges for the left or right pump adjustment will be required as described in step 6. If both pumps are within the initial calibration ranges skip to step 7.

6. If one pump is within the initial current ranges indicated in step 4 and the other is not, adjust the out of range pump to match initial current as outlined in step 7. If both pumps are out of the initial current ranges indicated in step 4 both pumps will require adjustment as outlined in step 7.

7. The pump neutral adjustment located on the main body of the EDC, ( locknut & threaded adjuster) requires 5/32 inch allen wrench and 1/2inch wrench, is adjusted as follows:

If the left pump is not within the desired range indicated in step 4, loosen the locknut and turn the adjuster counterclockwise 1/8th of a turn to increase the initial current value or turn clockwise to decrease, then re-calibrate as outlined in step 3. Check the resulting initial current value. Repeat this adjustment in 1/8th turn increments, or less, as required until the desired value is obtained repeating step 3 each time an adjustment is made. The goal is to get the left pump adjusted within the range as close to the middle of the range as possible and then adjust the right pump initial calibration current to match within 1 milliamp or less.

If the right pump does not match the left pump initial calibration current, counterclockwise adjustment will decrease the initial calibration current and clockwise will increase this value, note that this adjustment is opposite that of the left pump. Adjust as required in 1/8th turn or less increments repeating step 3 each time an adjustment is made until the right pump initial current matches the left within 1 milliamp or less.

8. Test the left and right pump reverse EDC coil initial calibration current using pins 11 & 34, while performing the reverse auto-calibration, "c12". The initial current values may not match each other but should be within 5 milliamps or less. Test drive the machine in pave range starting and stopping in forward and reverse at various speeds, 30 fpm, 60 fpm, 90 fpm and full pave speed. The machine should start and stop without "indexing" in forward. Some slight "indexing" may be noticed in reverse depending on how much difference exists in the left and right reverse initial current values. If the difference in the left and right pump reverse initial calibration currents exceeds 5 milliamps, or if the machine "indexes" excessively when starting and stopping in reverse the "PCP" (EDC coil and pilot control) should be tested and replaced if faulty. Refer to Technical Information Bulletin "1G-9335 Pressure Control Pilot (PCP) Performance Test Procedure" DATED 10/04/2000. Repeat auto-calibration, "C12" and performance tests.