Subaru 12033AB340 Piston Ring Set

Lay out the pistons and new ring sets to match each ring set with the corresponding piston and cylinder during the side clearance check, end gap measurement, and engine assembly. Before installing the rings, check the piston ring side clearance by placing a new ring in each groove and using a feeler gauge beside it, ensuring to check at several points around the piston and using the correct ring for each groove, as they differ. A typical clearance for compression rings is around 0.0015 to 0.004 inch (0.038 mm to 0.101 mm), and if excessive, new pistons will be necessary. The ring end gaps must also be verified, assuming the side clearance has been confirmed. Insert the top ring into the first cylinder, squaring it with the cylinder walls using the piston, and position it near the bottom of the cylinder. To measure the end gap, use feeler gauges between the ring ends until the correct gauge slides in with slight drag; typical gaps range from 0.010 to 0.020 inch (0.25 to 0.50 mm) for compression rings and up to 0.030 inch (0.76 mm) for oil ring steel rails. If the gap is too small, carefully file the ring ends to avoid contact during operation, ensuring to file only by pushing the ring from the outside end of the file towards the vise. Excess end gap is not critical unless it exceeds 0.040 inch (1.01 mm), and it's important to double-check the ring type. Repeat this process for each ring in the first cylinder and the remaining cylinders, keeping rings, pistons, and cylinders matched. Once the end gaps are checked and corrected, install the rings on the pistons, starting with the oil control ring, which consists of three components: first, insert the spacer/expander into the groove, then install the upper side rail without using a piston ring installation tool to avoid damage, and finally, install the lower side rail, ensuring the upper rail spin stopper aligns with the side hole in the piston. After installing the oil ring components, verify that both side rails rotate smoothly in their grooves. Next, install the middle ring, ensuring the identification mark faces up, and use a piston ring installation tool for both the middle and top rings, being careful not to confuse them. Finally, repeat the procedure for the remaining pistons and rings.

When preparing the pistons and new ring sets, make sure they are matched in order to allow checking of their side clearance, end gap measurement and engine assembly. Before putting the rings on it, ensure that the piston ring side clearance is right by inserting some new rings into each groove and employing a feeler gauge to test the spaces between them at various points around every groove. Distinct clearances exist for different rings; compression rings ordinarily have a clearance of about 0.0015 to 0.004 inches. Then, confirm that the ring end gaps fall within specifications by slightly dragging feeler gauges through the ring ends. The standard ring gap (compression ring) is 0.010" - 0.020". Smaller gaps can be adjusted by careful filing of ring ends. Avoid extremely large gaps over 0.040". Subsequently, mount the rings correctly on each piston starting with oil control ring as it has three parts namely spacer/expander, upper side rail and lower side rail which must be carefully inserted into their respective grooves without using a piston ring installation tool.Then make sure that both upper and lower rails can rotate smoothly.Putting number two(middle)ring in place there should be an identification mark pointing up while number one(top)ring should also face upwards with its mark repeating these steps for remaining pistons ensuring accurate installation for each.

Lay out the pistons and new ring sets to match each ring set with the corresponding piston and cylinder during the side clearance check, end gap measurement, and engine assembly. Before installing the rings, check the piston ring side clearance by placing a new ring in each groove and using a feeler gauge beside it, ensuring to check at several points around the piston and using the correct ring for each groove, as they differ. A typical clearance for compression rings is around 0.0015 to 0.004 inch (0.038 mm to 0.101 mm), and if excessive, new pistons will be necessary. The ring end gaps must also be verified, assuming the side clearance has been confirmed. Insert the top ring into the first cylinder, squaring it with the cylinder walls using the piston, and position it near the bottom of the cylinder. To measure the end gap, use feeler gauges between the ring ends until the correct gauge slides in with slight drag; typical gaps range from 0.010 to 0.020 inch (0.25 to 0.50 mm) for compression rings and up to 0.030 inch (0.76 mm) for oil ring steel rails. If the gap is too small, carefully file the ring ends to avoid contact during operation, ensuring to file only by pushing the ring from the outside end of the file towards the vise. Excess end gap is not critical unless it exceeds 0.040 inch (1.01 mm), and it's important to double-check the ring type. Repeat this process for each ring in the first cylinder and the remaining cylinders, keeping rings, pistons, and cylinders matched. Once the end gaps are checked and corrected, install the rings on the pistons, starting with the oil control ring, which consists of three components: first, insert the spacer/expander into the groove, then install the upper side rail without using a piston ring installation tool to avoid damage, and finally, install the lower side rail, ensuring the upper rail spin stopper aligns with the side hole in the piston. After installing the oil ring components, verify that both side rails rotate smoothly in their grooves. Next, install the middle ring, ensuring the identification mark faces up, and use a piston ring installation tool for both the middle and top rings, being careful not to confuse them. Finally, repeat the procedure for the remaining pistons and rings.

When preparing the pistons and new ring sets, make sure they are matched in order to allow checking of their side clearance, end gap measurement and engine assembly. Before putting the rings on it, ensure that the piston ring side clearance is right by inserting some new rings into each groove and employing a feeler gauge to test the spaces between them at various points around every groove. Distinct clearances exist for different rings; compression rings ordinarily have a clearance of about 0.0015 to 0.004 inches. Then, confirm that the ring end gaps fall within specifications by slightly dragging feeler gauges through the ring ends. The standard ring gap (compression ring) is 0.010" - 0.020". Smaller gaps can be adjusted by careful filing of ring ends. Avoid extremely large gaps over 0.040". Subsequently, mount the rings correctly on each piston starting with oil control ring as it has three parts namely spacer/expander, upper side rail and lower side rail which must be carefully inserted into their respective grooves without using a piston ring installation tool.Then make sure that both upper and lower rails can rotate smoothly.Putting number two(middle)ring in place there should be an identification mark pointing up while number one(top)ring should also face upwards with its mark repeating these steps for remaining pistons ensuring accurate installation for each.