REP-TAT-P-1125-05 Check end clearance of piston rings
WARNING: This page is about a different car, the 2018 BMW 340i, 2017 BMW 340i, and 2016 BMW 340i. However, it is still accessible from the selected car via links, so may be relevant.
Prerequisite
Cylinder path is cleaned. Cylinder was measured and is within the permissible tolerances.
NOTE:
Schematic diagram is for example purposes. Some parts may differ in certain details.
Check
- Insert upper piston ring into the cylinder and slide to TDC with the pistons.
- Check the end clearance of the upper piston ring with a feeler gauge.
TECHNICAL DATA SPECIFICATIONS
| End clearance of upper piston ring | |
|---|---|
| Before measuring the end clearance, make sure the cylinder is within the permissible tolerance. | 0.20 mm... 0.28 mm |
Result
» End clearance is outside tolerance.
Measure
- Replace upper piston ring.
Check
- Take upper piston ring out of the cylinder.
- Insert center piston ring into the cylinder and slide to TDC with the pistons.
- Check the end clearance of the center piston ring with a feeler gauge.
TECHNICAL DATA SPECIFICATIONS
| End clearance of center piston ring | |
|---|---|
| Before measuring the end clearance, make sure the cylinder is within the permissible tolerance. | 0.20 mm... 0.28 mm |
Result
» End clearance is outside tolerance.
Measure
- Replace center piston ring.