Cylinder Block Assembly: Testing and Inspection
Measuring pistons (includes measuring cylinder bore)Preliminary work
1. Remove pistons.
Information
Component overview
Component Overview Of Piston:
Measuring pistons (includes measuring cylinder bore)
1. Clean removed pistons with solvent naphtha. To achieve an accurate result, any carbon deposits must be carefully removed, e.g. with a brass brush.
Piston Dimensions:
Measuring Pistons With A Micrometer:
2. Test piston diameter -D- at the piston shank (at 90° to the axis of the piston pins) using a micrometer (measuring range 75 - 100 mm). Measured from the lower edge of the shank, the height X -X on the shank is 6 mm.
Note: If the wear limit is exceeded, the piston must be replaced!
The maximum wear allowed on specified measuring point is 0.04 mm. If this measurement is exceeded, the piston must be replaced. The reference measurement for the piston dimensions is to be taken from the following Table.
When pistons are worn, the wear on the cylinder should also be tested (see below: "Measuring cylinder bore").
Measuring piston ring play
1. Remove crankshaft.
2. Insert the piston ring from top to bottom at right angles to the cylinder wall, about 1.5 mm from the edge of the cylinder. To insert it, use a piston with no piston ring
Piston Ring Play:
3. Measure the play in the ring gap with a feeler gauge. Compare the value with the Table.
4. If the measurement for the wear equals or exceeds the limit, the piston rings should be replaced. In addition, the wear on the cylinder should also be determined (see below: "Measuring cylinder bore").
Measuring piston ring height play
1. Clean removed pistons with solvent naphtha. To achieve an accurate result, any carbon deposits must be carefully removed, e.g. with a brass brush.
2. Take special care to clean the ring groove before testing
Play In Height:
3. Determine the play in height between the piston ring and the ring groove.
4. If the measurement for the wear equals or exceeds the limit, the piston rings and the corresponding piston should be replaced.
Measuring cylinder bore.
1. Prepare the cylinder bore for measuring and clean it with a cloth. Any carbon deposits should be removed using a soft brass wire brush
Dial Gauge -1 And Internal Vernier Gauge -2 Inside The Cylinder Bore:
2. Using a vernier gauge for measuring internal dimensions -1 and 2- (measuring range 50 - 100 mm) make measurements of the diagonals at three positions in transverse and longitudinal directions --> Dial gauge - 1 and internal vernier gauge - 2 inside the cylinder bore.
Measuring Points Inside The Cylinder Bore:
3. The measuring device should be zero calibrated within the top 10 mm from the edge before the actual measurement is made, since in this region there will be no wear. Thereafter perform the measurement
4. If the measurement for the wear equals or exceeds the limit, the engine should be replaced.
Subsequent work
1. Install pistons.