Audi A3 Quiz
Engine

Overhaul - Measuring Cylinders

In this manual: Engine
Owner's Manual — 42Routine Care and Maintenance — 32Engine — 22Engine Cooling System — 9Ventilation, Heating and Air Conditioning Systems — 11Fuel System — 9Fuel Injection System — 4Diesel engine injection system — 5Exhaust System — 9Electronic Ignition and Fuel Injection Control System — 6Charging and Starting Systems — 12Manual transmission — 12Clutch and Drive Shafts — 6Brake System — 13Front Suspension — 5Rear Suspension — 6Steering — 7Body — 70Body Electrical Equipment — 37Wiring Diagrams — 35
~1min read

GENERAL INFORMATION

To measure the cylinders, use a dial bore gauge, which allows measurements at the top, middle and bottom of the cylinder. If a dial bore gauge is not available, this operation cannot be performed.

PROCEDURE

1. Measure the cylinder in directions A and B. In addition, take measurements 10 mm from the top edge, 10 mm from the bottom edge and in the middle, i.e. at levels 1, 2 and

3. In total, take six measurements on each cylinder. Record all measured values and compare them with the values given in the Specifications.

2. Note that all cylinders must be bored, even if the dimensions of only one cylinder are out of specification. A deviation of 0.8 mm from the nominal value is permissible. Repair piston sizes are given in the Specifications.

3. The final cylinder size is determined after measuring the piston diameter, taken 10 mm from the bottom edge of the piston skirt and at the right angle to the piston pin bore.

4. Then add the piston clearance of 0.03 mm to this size. In addition, add 0.02 mm for honing the cylinder.

5. To check the piston-to-cylinder clearance, measure the piston and cylinder as described above and calculate the difference between these values. If the result exceeds 0.08 mm, the cylinders must be bored, since the clearance has reached the wear limit.

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A quick Audi A3 quiz: every answer comes with an explanation and a link to the manual page.