Step 2: Checking the piston ring grooves
If between a parallel sided compression ring and the associated groove flank a distance of 0.12 mm or more is measured, the piston is excessively worn and must be replaced.
Usability of the pistons | Groove clearance (mm) |
---|---|
Pistons can be used without concern | 0,05 – 0,10 |
Increased caution is required | 0,11 – 0,12 |
A new piston must be used! | > 0,12 |
Special:
Installation of steel rail spring washers
Installation of steel rail spring washers
Note:
With three-digit steel rail spring washers, it can happen that the expander spring overlaps on the joint ends. For this reason, always control the position of expander feathers before installing the pistons.
With three-digit steel rail spring washers, it can happen that the expander spring overlaps on the joint ends. For this reason, always control the position of expander feathers before installing the pistons.
Step 7: Function test / Twisting the piston rings
Once the piston rings are installed, it must be ensured that they can move freely. Twist the joint ends of the piston rings by 120° each on the piston.
Note:
Pistons for two-stroke engines with piston rings which are secured against twisting must not be twisted when inserted into the cylinders. In this process, the locking pin can move below the piston ring sprung outwards in the area of a cylinder window and break this off at the opposite window edge.
Pistons for two-stroke engines with piston rings which are secured against twisting must not be twisted when inserted into the cylinders. In this process, the locking pin can move below the piston ring sprung outwards in the area of a cylinder window and break this off at the opposite window edge.
Step 8: Inserting the piston into the cylinder liner
Sufficiently oil piston rings and pistons and install with a closing piston ring clamp or a conical assembly sleeve to prevent the piston rings from being damaged.
Kolbenschmidt art. no. | Name |
---|---|
50 009 816 | Piston ring scuff band for ΓΈ 57 – 125 mm |
50 009 828 | Piston ring scuff band for ΓΈ 90 – 175 mm |
50 009 913 | Piston ring assembly kit set |