TB-9-2350-368-25 Powerplant Test Stand M113A2 M113A3 M548A1 M548A3 Download

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TM 9-2350-368-25 5-1 CHAPTER 5 POWERPLANT TEST STAND SECTION I. MAINTENANCE 5.1. PURPOSE. The purpose of this chapter is to give some ideas of how to maintain the powerplant test stand and ways of finding out if the powerplant test stand is at fault when you get the wrong readings while testing a powerplant. The powerplant test stand is a very simple test stand. It contains all the necessary indicators and gauges needed to verify that everything is working. The only maintenance that should be done on a regular schedule is cleaning and charging of the batteries. If the powerplant test stand has axles and wheels, some lubricating may be needed. CAUTION Instrument panel/box is not sealed and water or moisture may cause electrical short. Never steam clean or wash with water under pressure. When cleaning instrument panel/box, clean the same as you would clean the instrument panel in a vehicle or by hand wiping using any authorized cleaning agent available. SECTION II. TROUBLESHOOTING 5.2. INTRODUCTION. This section is about troubleshooting. Troubleshooting is limited to checking wiring of the powerplant test stand. For troubleshooting of the powerplant, refer to TM 9-2350-277-20-1 or to the technical manual of the powerplant that is being tested. For troubleshooting the batteries, refer to TM 9- 6140-200-14. The cooling system should not need troubleshooting. If a leak occurs, repair it. The only difference in troubleshooting the powerplant is that additional circuit breakers have been added at the instrument panel/box to aid you in isolating electrical circuit. See wiring diagram. Circuit breaker number 1: This circuit breaker tells you that something is wrong with the starting system/transmission controller (A3 only). Circuit breaker number 2: This circuit breaker tells you that something is wrong with charging system/alternator field switch. Circuit breaker number 3: This circuit breaker tells you that something is wrong with air box heater/cold start system. Circuit breaker number 4: This circuit breaker tells you that something is wrong with instrument panel system—lights/ gauges etc. When a circuit breaker trips, do not assume that the problem is in the powerplant. Like any troubleshooting, you must consider everything in the particular electrical string. For example, if circuit breaker number 1 trips, you must verify that the components in the instrument panel/box are working properly before condemning the powerplant starter. You must also verify that there is not a short in the wiring harness.