TM 10-3930-669-34 1.  ENGINE CRANKS BUT WILL NOT RUN (CONT). KNOWN INFO TEST OPTIONS Injection pump OK. Visual inspection. Injection pump timing OK. Camshaft gear alignment OK. REASON FOR QUESTION Engine compression OK. Cylinder heads and gaskets OK Cylinder heads and gaskets OK. If piston(s) is faulty, engine will Piston crown clearance OK. not run. Valves and valve springs OK. POSSIBLE PROBLEMS Piston(s) faulty. Piston ring(s) faulty. KNOWN INFO TEST OPTIONS Injection pump OK. Visual inspection. Injection pump timing OK. Camshaft gear alignment OK. REASON FOR QUESTION Engine compression OK. Cylinder heads and gaskets OK. Cylinders OK. If piston ring(s) is faulty, engine Piston crown clearance OK will not run. Valves and valve springs OK. Pistons OK.- POSSIBLE PROBLEMS Piston ring(s) faulty. Replace piston(s) or engine (Para 3-13 or 3- 3). Go to Step 11 of this Fault. Replace piston rings or engine (Para 3-13 or 3- 3).  Go to Step 11 of the Fault. 2-20