VW CGRA - Checking Piston and Cylinder

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❑ To measure radial clearance, tighten to 40 Nm but not further.
8 - Cylinder block
❑ Checking cylinder bores ⇒ page 58 .
❑ Removing and installing crankshaft ⇒ page 49 .
❑ Piston and cylinder dimensions ⇒ page 61 .
9 - Piston pin
❑ If difficult to remove, heat piston to 60°C.
❑ Remove and install using drift - VW 222 A- .
4.2 Checking piston and cylinder
Checking piston ring gap ⇒ page 57 .
Checking ring-to-groove clearance ⇒ page 57 .
Checking piston ⇒ page 58 .
Checking cylinder bore ⇒ page 58 .
Installing piston ⇒ page 58 .
Piston and cylinder dimensions ⇒ page 61
4.2.1 Checking piston ring gap
Special tools and workshop equipment required
♦ Feeler gauge
Test sequence
– Push ring at right angles to cylinder wall from above down to
approx. 15 mm from bottom end of cylinder. Push in using a
piston without rings.
Piston ring Ring gap
New Wear limit
Rectangular-section ring mm 0.20 … 0.40 1.0
Tapered stepped ring mm 0.20 … 0.40 1.0
Oil scraper ring mm 0.25 … 0.50 1.0
4.2.2 Checking ring-to-groove clearance
Special tools and workshop equipment required
♦ Feeler gauge
Clean annular groove before check.
Piston ring Clearance
New Wear limit
Rectangular-section ring mm 0.04 … 0.09 0.15
Tapered stepped ring mm 0.03 … 0.06 0.15
Oil scraper ring mm 0.02 … 0.06 0.15
Touareg 2010 ➤ , Touareg 2015 ➤
6-cylinder direct-injection engine (3.6 l engine, 4V) - Edition 12.2019
4. Pistons and conrods 57