11 25 Pistons, Rings, and Pins (N55)
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2015 BMW 740i, 2015 BMW 740Li xDrive, 2015 BMW 740Li, 2014 BMW 740i, and 2014 BMW 740Li xDrive. However, it is still accessible from the selected car via links, so may be relevant.
PISTONS, RINGS, AND PINS SPECIFICATION - 1 OF 2
| 1st groove | ||
| End clearance | mm | 0.15...0.30 |
| Side clearance | mm | 0.020...0.060 |
| 2st groove | ||
| End clearance | mm | 0.30...0.50 |
| Side clearance | mm | 0.015...0.060 |
| 3rd groove | ||
| End clearance | mm | 0.20...0.90 |
| Side clearance | mm | can't be measured |
PISTONS, RINGS, AND PINS SPECIFICATION - 2 OF 2
| Piston and pin are paired to each other - replace together only. | ||
| Measuring point "A" (position) | mm | 12 |
| Piston diameter at measuring point "A" | ||
| Original (new dimension) | mm | 83.98... 84.01 |
| Repair stage (new dimension) | mm | 84.06... 84.09 |
| Oversize (new dimension) | mm | 84.23... 84.26 |
| Piston installation clearance (piston new) | mm | 0.01...0.03 |
| Piston installation clearance (piston worn) | mm | 0.02...0.08 |
| Permissible total wear tolerance between piston and cylinder (engine operated) | mm | 0.15 |