TM 5-3895-359-14&P
V.P.I. TROUBLE SHOOTING
PROBLEM
POSSIBLE CORRECTION
No flow in system.
1, 2, 3, 4, 5, 6, 7
Gallons per minute indicator not working with flow in system and meter totalize
registering.
8, 9, 10, 11, 12, 13
Meter totalizer not registering with flow in system.
11, 12
Feet per minute indicator not working with tach wheel turning.
8, 9, 10, 13
Performance meter not centered with proper f.p.m. - g.p.m. indicator readings for
corresponding gallons per square yard setting.
14
Rapidly varying gallons per minute indicator reading.
3, 15, 16
Rapidly varying feet per minute indicator reading.
9, 10, 17
POSSIBLE CORRECTION
1. Pump engine not running. Start engine.
2. Tank truck outlet plugged. Check outlet valve and/or strainer.
3. Suction line air leak. Tighten connections.
4. Strainer clogged. Check and clean strainer.
5. Pump not primed. Prime pump.
6. Metering valve closed. Open metering valve.
7. Tank truck going down grade or empty. Check capacity.
8. Tach-generator polarity reversed.
9. *Tach-generator not putting out voltage.
10. Loose connection or broken wire. Tighten or replace wiring.
11. Meter propeller not turning.
12. Meter propeller turning, but not the meter gear train, indicates something is binding in the meter gear train. Check
13. Faulty indicator if tach-generator is putting out voltage, but indicator not registering.
14. Check application rate unit calibration for one (1) ohm reading with pointer at zero ("0"). (See calibration procedure.)
15. Pulsating flow in system. (Check 3, 7, 10, 16)
16. Pump engine not running at constant speed.
17. Tach wheel bouncing, skidding, not lowered completely.
*Tach-generator voltage may vary with an oil or moisture film on the commutator and brushes. Inspect and clean
thoroughly.
13-7
