F 350 4WD Pickup V8-351 5.8L VIN H EFI (1997)
Piston Ring: Testing and Inspection
Fitting
Do not reinstall used piston rings. A special break-in finish, and sometimes an anti-scuff coating, is applied to new piston rings by the factory. The
purpose of the special finish is to help the new piston rings and cylinder bore mate properly. The special finish, like the crosshatching on the cylinder
bore, wears off during break-in. The special finish will be already worn off used rings so they will not seat properly. For this reason attempting to reuse
piston rings can lead to excess oil consumption and possible cylinder scoring.
1. Insert each piston ring backwards (see illustration) in the piston ring groove into which it will be installed.
2. Measure the clearance between the ring and groove (side clearance) with a feeler gauge and check against the side clearance specifications.
3. Insert the ring in the cylinder bore.
4. Using the piston, without rings, turned upside down, press the ring down to the center of the bore.
5. Make sure that the ring is "square" in the bore.
