Teledyne TSIO-360-RB, Maintenance Manual

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20-12
10. If the leakage is below the previously determined low cylinder gauge reading, loss past the
dynamic seal may be due to piston ring end gap alignment or by the piston and piston rings
angular direction in the cylinder bore see Figure 20-11,"Ring Positioning." First insure that
the piston and piston rings are centered. This can be accomplished by reducing regulator
pressure to 20 pounds per square inch and working piston through top dead center several
times bringing the piston to top dead center in the normal direction of engine rotation.
Adjust regulated pressure to 80 pounds per square inch and determine amount of loss. If
the gauge reading is higher than the previously determined master orifice calibrated
reading, proceed to next cylinder to be tested.
NOTE. . . Piston ring rotation within the ring land is a normal design characteristic. As
illustrated in Figure 20-11, "Ring Positioning," the compression ring location may have a
direct bearing on the dynamic seal pressure check. Therefore, complete the test in the
opposite direction if readings are below prescribed limits.
FIGURE 20-11. RING POSITIONING
11. If recheck of cylinder pressure gauge reading indication remains below allowable loss,
engine may be run up to operating temperature and rechecked prior to cylinder being
removed and repaired. Rework of cylinders must be accomplished in accordance with
"Cylinder Assembly Repair And Replacement" in the L/TSIO-360 Series Overhaul
Manual, Form X30596A.
TOP COMPRESSION
RING GAP
T.D.C.
DIRECTION
OF
MOVEMENT
T.D.C.
DIRECTION
OF
MOVEMENT
TOP COMPRESSION
RING GAP