Mopar MD104925 V6-Piston (OUTSIDEIZE 0.75)

Before installing the new piston rings, the ring end gaps must be checked, assuming the piston ring side clearance has been verified correct. Lay out the piston/connecting rod assemblies and the new ring sets to match them with the same piston and cylinder during the end gap measurement and engine assembly. Insert the top ring into the first cylinder, ensuring it is square with the cylinder walls by pushing it in with the top of the piston, positioning the ring near the bottom of the cylinder. To measure the end gap, use feeler gauges between the ends of the ring until a gauge equal to the gap width is found, ensuring the feeler gauge slides with slight drag. If the gap is too small, it must be enlarged to prevent the ring ends from contacting each other during engine operation, which can cause serious damage; this can be done by carefully filing the ring ends from the outside in. Excess end gap isn't critical unless it exceeds 0.040-inch, so double-check to ensure the correct rings are being used. Repeat the procedure for each ring in the first cylinder and the remaining cylinders, keeping rings, pistons, and cylinders matched. Once the ring end gaps have been checked and corrected, install the rings on the pistons, starting with the oil control ring, which consists of three components. Slip the spacer/expander into the groove, ensuring any anti-rotation tang is inserted into the drilled hole in the ring groove. Install the lower side rail by placing one end into the groove and pushing it in with a finger, then do the same for the upper side rail. After installing the three oil ring components, check that both side rails can turn smoothly in the groove. Next, install the middle ring, ensuring the identification mark faces up, and use a piston ring installation tool to slide it into the middle groove without expanding it more than necessary. Finally, install the top ring in the same manner, ensuring the mark is facing up, and repeat the procedure for the remaining pistons and rings.