When you’re diagnosing engine problems in an M113-series vehicle, save yourself a lot of trouble and your unit a lot of money by following not only the troubleshooting procedures in TM 9-2350-277-13&P (IETM EM 0321, Oct 14), but also those in TM 9-2815-205-24 (Feb 13).
If you have an engine that’s overheating, for example, the troubleshooting procedures in the IETM would have you to replace the water pump ($614), head gaskets ($142) and other cooling-related components to resolve the problem. But, in reality, a bad thermostat might be the problem. And TM 9-2815-205-24 tells mechanics exactly that. Many times, engine overheating is fixed by a simple $55 thermostat replacement instead of swapping out other, more costly components.
Another example is when diagnosing an engine with low power. The IETM doesn’t say anything about adjusting the rack (injector timing), but the engine TM does.
The bottom line
is that you should use both manuals when troubleshooting engine-related faults!