Skoda Workshop Service and Repair Manuals

Piston and conrod - Summary of components   Note Secure the engine with the engine mount -MP1-202- and the distance sleeves -T30010- on the assembly stand -MP9-101- before performing the assembly work → Chapter.

1 -	Piston rings

q	Offset joint 120°

q	use piston ring pliers for removing and installing

q	Marking „TOP“ faces up

q	Inspect gap clearance → Fig.

q	Inspect end clearance → Fig.

2 -

Piston

q	check → Fig.

q	mark installation position and matching cylinder

q	arrow on piston crown faces towards the belt pulley side

q	use piston ring tensioning strap for installing

q	Ø Piston: 82.465 mm

3 -	Piston pin

q	if stiff, heat piston to 60°C

q	with drift -VW 222 A- removing and installing

4 -

Circlip

q

replace

5 -

Conrod

q	with a split bearing cap

q	with oil drilling for lubricating piston pin

q	always replace as a set → Electronic Catalogue of Original Parts

q	Mark assignment to cylinder -arrow A-

q	Fitting position: Marking -arrow B- points towards the belt pulley side

q	Axial play when new: 0.10...0.35 mm, wear limit: 0.4 mm

6 -	Bearing shell

q	pay attention to different versions → Electronic Catalogue of Original Parts.

q	at top with oil drilling for piston pin lubrication

q	check fitting position → Fig.

q	do not mix up used bearing shells (mark)

q	ensure tightly located in retaining lugs

7 -	Cylinder block

q	inspect cylinder bore → Fig.

q	Ø Cylinder: 82.51 mm

8 -	Conrod bearing cap

q	as a result of the conrods separated in the cracking process, the cover fits only in one position

q	Mark assignment to cylinder -arrow A-

q	Fitting position: Marking -arrow B- points towards the belt pulley side

9 -	Oil injection nozzle

q	for piston cooling

q	delivered together with Pos. 10

10 -	Pressure valve, 27 Nm

q	opens at a pressure of 0.13...0.16 MPa (1.3...1.6 bar)

q	delivered together with Pos. 9

q	install without sealant

11 -	30 Nm + torque a further 90° (1/4 turn)

q	replace → Electronic Catalogue of Original Parts

q	Oil thread and contact surface

Inspecting piston ring gap clearance Special tools and workshop equipment required t  Feeler gauge Test sequence –  Push in ring at right angles to the cylinder wall from the top through to the bottom cylinder opening, about 15 mm from the cylinder edge. To insert use piston without rings.

Piston ring		Gap clearance
		new	Wear limit
Compression rings	mm	0,20...0,40	0,80
Oil scraper ring	mm	0,25...0,50	0,80

Inspect piston ring end clearance Special tools and workshop equipment required t  Feeler gauge Test sequence –  Clean the annular groove before inspecting.

Piston ring		End clearance
		new	Wear limit
Compression ring	mm	0,06...0,09	0,20
Oil scraper ring	mm	0,03...0,06	0,15

Inspecting pistons Special tools and workshop equipment required t  External micrometer 75...100 mm Test sequence –  Measure about 10 mm from the lower edge and vertically offset to piston pin axis. t  Deviations from specified dimension: max. 0.04 mm

Bearing shell installation position Bearing shell -1- with oil drilling -arrow- for conrod. Bearing shell -2- without oil drilling for conrod bearing cap. –  Insert bearing shells in the conrod and in the conrod bearing cap centred. The dimension -a- must be the same on both sides, max. deviation: 0.2 mm.

Inspecting cylinder bore Special tools and workshop equipment required t  Internal precision measuring instrument 50...100 mm Test sequence –  Measure at 3 points crosswise in a transverse direction -A- and lengthwise -B-. t  Deviations from specified dimension: max. 0,08 mm   Note Do not measure the cylinder bore if the cylinder block is fixed to the assembly stand with the engine mount -MP1-202-, as this may result in incorrect measurements.