Piston Rings: Installation

The No. 1 and No. 2 piston rings have a different cross section. Install rings with manufacturers I.D. mark facing up, to the top of the piston. See Fig 1.

Fig 1: Piston Ring Installation

Courtesy of DAIMLERCHRYSLER CORP.

1. Oil ring expander
2. Lower oil ring side rail
3. Upper oil ring side rail
4. No. 2 intermediate piston ring
5. No. 1 upper piston ring

1. Install oil ring expander.
2. Install the lower oil ring side rail by placing one end between the piston ring groove and the expander. Hold end firmly and press down the portion to be installed until side rail is in position. Do not use a piston ring expander.  . See Fig 2.
   Fig 2: Side Rail-Installation

   Courtesy of DAIMLERCHRYSLER CORP.

   1 - SIDE RAIL END

3. Install upper oil ring side rail.
4. Install No. 2 piston ring and then No. 1 piston ring. See Fig 3.
5. Position piston ring end gaps as shown in Fig 4.
6. Position oil ring expander gap at least 45° from the side rail gaps but not  on the piston pin center or on the thrust direction. Staggering ring gap is important for oil control.

Fig 3: Upper and Intermediate Rings-Installation

Courtesy of DAIMLERCHRYSLER CORP.

Fig 4: Piston Ring End Gap Position

Courtesy of DAIMLERCHRYSLER CORP.