Cylinder Block — Cleaning and Checking (Opel Astra G)

Cleaning

1. Remove all attachments from the cylinder block, unscrew the sensors. Remove the plugs by drilling holes in the plugs, screwing a self-tapping screw into each and pulling them out with pliers by the screw heads.

2. Carefully clean the cylinder block from any remaining gasket material.

3. Remove all oil passage plugs (if provided). These plugs are screwed in very tightly, so they may need to be drilled out and then tapped. When assembling the engine, replace all plugs.

4. In case of severe contamination of the cylinder block, steam cleaning will be required.

5. After steam cleaning the block, repeat the cleaning of the oil holes and passages. Rinse all internal passages of the cylinder block with warm water until clean water begins to flow. Dry the block thoroughly and lubricate all split and ground surfaces to prevent corrosion.

6. If the surface of the cylinder block is moderately dirty, you can limit yourself to washing the cylinder block with a hot soapy solution.

7. Clean the threaded holes and tap the threads.

8. Lubricate the new plugs with sealant and screw them into the cylinder block.

9. If engine assembly is postponed, lubricate the cylinder block surfaces and cover the entire block with plastic film.

Examination

10. Visually check the cylinder block for cracks and traces of corrosion. Check the condition of the threads in the holes, mark the places with stripped threads. If there was a suspicion of a coolant leak inside the cylinder block, then the block should be tested for leaks, for which you should contact a workshop. If defects are found, repair the block (if possible), or replace.



11. Check for chips and burrs on the inner surfaces of the cylinders.

Check for a ridge at the top of the cylinder, which indicates increased cylinder wear.

12. Measure the inside diameter of the cylinder just below the wear flange, parallel and perpendicular to the engine axis. Repeat the measurements in the middle of the cylinder and at the bottom edge. Based on the results of these six measurements, determine the taper and ovality of the cylinder. Compare the results with the standard (the cylinder size group designation is stamped onto the cylinder block)If the measured values exceed the limit, the block should be bored and repair pistons installed (or replace and install new pistons). In case of severe damage to the cylinders, replace the block.

13. If the cylinders are in satisfactory condition, then only the piston rings will need to be replaced. In this case, the cylinders are only subjected to honing, which ensures better running-in of the piston rings and their tight fit to the cylinder walls (performed at a service station).