Valve Spring
| Part # | 180 053 06 20 | 615 053 01 20 Valve Spring of Engine 617.950 (USA) Model Year 1980 with increased output and of Engines 617.951/952. | |
| Color Code | Green or Purple | Yellow-Yellow or Purple-Yellow | |
| Outer Diameter | 30.2 mm | 30.4 mm | |
| Wire Gauge | 3.8 mm | 3.9 mm | |
| Free Length | 50.5 Millimeter (mm) | 51.2 Millimeter (mm) | |
| Spring Force at Length | New | 463 - 530 at 29.9 Newton At Millimeter (N @ mm) | 589 at 28.0 Newton At Millimeter (N @ mm) |
| Tolerance Limit | 417 at 29.9 Newton At Millimeter (N @ mm) | 530 at 28.0 Newton At Millimeter (N @ mm) |