11 25 671 Replacing piston rings on all pistons (M52 / S52 / M52TU / M54 / M56)

WARNING: This page is about a different car, the 2005 BMW 530i, 2005 BMW 525i, 2004 BMW 530i, and 2004 BMW 525i. However, it is still accessible from the selected car via links, so may be relevant.

(piston removed)

Remove piston rings with a piston-ring compressing pliers.

NOTE: It might not be possible to find the identification on used piston rings.

Put aside piston rings in correct sequence and installation position.

Only install new pistons in conjunction with new piston rings.

Fig 1: Removing Piston Rings

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Installation:

Install piston rings with "TOP" to piston top.

Plain compression ring
Stepped compression ring "Top"
Slotted oil ring with hose spring clip

Fig 2: Installing Piston Rings With "TOP" To Piston Top

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Measure axial play.

Fig 3: Measuring Axial Play

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Measure end clearance.

Fig 4: Measuring End Clearance

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