Standard Procedure - Piston Ring Fitting

WARNING: This page is about a different car, the 2015 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Measuring Piston Ring End Gap

Courtesy of CHRYSLER GROUP, LLC

Wipe the cylinder bore clean.
Using a piston, to ensure that the ring is squared in the cylinder bore, slide the ring downward into the cylinder to a position 12 mm (0.50 in.) from the bottom of the cylinder bore.

Using a feeler gauge (1), check the ring end gap. Replace any rings not within specification.

Ring Position	Ring End Gap
No. 1 Ring (Top)	0.20 - 0.35 mm (0.008 - 0.014 in.)
No. 2 Ring (Center)	0.40 - 0.60 mm (0.016 - 0.024 in.)
Oil Control Ring (Bottom)	0.20 - 0.40 mm (0.008 - 0.016 in.)

Fig 2: Checking Piston Ring Grooves Clearances

Courtesy of CHRYSLER GROUP, LLC

Clean the piston ring grooves. Remove any nicks or burrs.
Measure the ring side clearance as shown in illustration. Make sure the feeler gauge (1) fits snugly between the ring land and the ring. Replace any ring not within specification.

Ring Position	Ring Side Clearance
No. 1 Ring (Top)	0.030 - 0.070 mm (0.0012 - 0.0028 in.)
No. 2 Ring (Center)	0.020 - 0.060 mm (0.0008 - 0.0024 in.)
Oil Control Ring (Bottom)	0.020 - 0.055 mm (0.0008 - 0.0022 in.)