SEAT Workshop Service and Repair Manuals

• Piston ring
• ◆ Offset gaps by 120 °
• ◆ Remove and install with piston ring pliers
• ◆ "TOP" faces towards piston crown
• ◆ Checking ring gap=> Fig. 1
• ◆ Checking ring to groove clearance
  => Fig. 2
• Piston
• ◆ Checking => Fig. 3
• ◆ Mark installation position to conrod and cylinder number
• ◆ Lower side of piston crown faces towards centre of cylinder block
• ◆ Install with piston fitting tool 3278
  => Fig. 5
• Circlip

• Conrod
• ◆ Only renew as a set
• ◆ Mark cylinder number -B-
• ◆ Installation position:
  Marks -A- must be above one another
• Bearing shell
• ◆ Note installation position
• ◆ Do not interchange used bearing shells
• ◆ The lugs on the bearing shells must fit tightly in the recesses
• ◆ Axial clearance
  New: 0.05...0.35 mm
  Wear limit: 0.40 mm
• ◆ Check radial clearance with Plastigage:
  New: 0.02...0.07 mm
  Wear limit: 0.10 mm
  Do not rotate crankshaft when
  checking radial clearance

• Conrod bearing cap
• ◆ Mark cylinder number -B-
• ◆ Installation position:
  Marks -A- must be above one another
• 30 Nm + 1/4 turn (90 °) further
• ◆ Renew
• ◆ Oil threads and contact surface
• ◆ To measure radial clearance tighten to 30 Nm but not further
• Cylinder block
• ◆ Checking cylinder bores
  =>Fig. 4
• ◆ Removing and installing crankshaft
• ◆ Piston and cylinder dimensions
  

• Piston pin
• ◆ If difficult to remove, heat piston to 60 °C
• ◆ Remove and install with drift VW 222a

→ Fig. 1    Checking piston ring gap

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Feeler gauges

Test sequence

• ‒ Push ring squarely from above down to approx. 15 mm from bottom end of cylinder. To do this use a piston without rings.

→ Fig. 2    Checking ring to groove clearance

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Feeler gauges

Test sequence

• ‒ Clean ring groove before checking.

→ Fig. 3    Checking piston

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Micrometer 75...100 mm

Test sequence

• ‒ Take measurement about 6 mm from lower edge of piston skirt and offset 90 °to piston pin axis.

• Deviation from specification
      max. 0.04 mm.

→ Fig. 4    Checking cylinder bores

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Internal dial gauge 50...100 mm

Test sequence

• ‒ Take measurements at right angles -A- and -B- at 3 positions.

• Deviation from specification
      max. 0.08 mm.

Note:

The cylinder bores must not be measured if the cylinder block is mounted on a repair stand with engine bracket 3269 or VW 540, as incorrect measurements would then be possible.

→ Fig.5    Installing pistons with piston fitting tool 3278

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ 3278 Funnel

Note:

If a new fitting tool (funnel) is used to install the pistons, first pass piston with oiled piston rings twice through the tool and then if necessary remove the resulting metal shavings. Only then install piston with piston rings.

Work sequence

• ‒ Oil funnel and push piston in by hand. Lower side of piston crown must face lug on funnel -arrow-.
• ‒ Hold tool (with piston inserted) on upper edge and press piston in with both thumbs.
• ‒ Push piston in until it protrudes approx. 15 mm from the lower edge of the fitting tool.
• ‒ Place piston in appropriate cylinder bore. Lug on fitting tool -arrow- must face to centre of cylinder block.
• ‒ Hold fitting tool tight against cylinder block and push piston in.