Subaru 12108AB020 Bearing Set Connecting Rod

Once the crankshaft and connecting rods have been cleaned and inspected, and a decision has been made regarding bearing replacement, the connecting rods can be reinstalled on the crankshaft. If new bearings are being used, check the oil clearances before the final installation of the connecting rods. If the clearances are within the specified limits, proceed with the installation. Never assume that the clearances are correct, even if new bearings are involved. Make sure the bearing faces and backs are perfectly clean, then fit them to the connecting rod and cap. The tab on each bearing must be engaged in the recess in the cap or connecting rod. Clean the number one connecting rod journal on the crankshaft, then slip the number one connecting rod into place. Ensure that the mark on the side of the connecting rod is facing the front of the crankshaft. Apply a length of Plastigage to the crankshaft journal, just off-center. Gently install the connecting rod cap in place, without turning the connecting rod on the journal. Make sure the mating mark on the cap is on the same side as the mark on the connecting rod. Lubricate the threads of the connecting rod nuts or bolts and tighten them. Remove the connecting rod nuts or bolts without allowing the connecting rod to turn on the journal, then remove the cap. Examine the Plastigage and compare its width to the scale on the Plastigage package. The connecting rod oil clearance is usually about 0.001 to 0.002 inches. Consult an automotive machine shop for the clearance specified for the rod bearings on your engine. If the clearance is within specifications, proceed with checking the other three connecting rods. If the connecting rod clearances are all within specifications, lubricate both halves of the bearings of connecting rod number 1 with moly-based assembly lube and install the connecting rod nuts or bolts. Tighten them, working up to it in three steps. Repeat the procedure for the remaining connecting rods. Do not mix up the connecting rods and caps, and do not install the connecting rods backwards. After the connecting rods have been installed, rotate them by hand and check for any obvious binding. As a final step, recheck the connecting rod side clearance.

Before removing the connecting rods from the crankshaft, turn the engine with the feeler gauge, and observe the end play (side clearance, connecting rod to crankshaft throw) then do the same for the other rods also. The end play is equal to the thickness of the feeler gauge(s), it is recommended to consult an automotive machine shop for end play service limit which generally ranges from to .050 to .015" (0.127 to 0.369 mm). Past this range, new connecting rods will be required in the play of the drill string. In some instances, new rods or a new crankshaft might be inserted, and the resultant end clearance is located below the postoperatively minimum standard; hence, some machining of the rods or seeking advice with an automotive machine shop. If the rods and caps are not numbered, then try to number them in order that they could be refitted between the related cylinder and crankshaft journal, the usage of permanent ink or paint layer. With the crankshaft facing up, place one dot at the connecting rod and cap at the front of the crankshaft, mark the second one with two dots, and so on, both the rods and caps should be marked since they will needs to be separated later. After loosening the cap nuts/bolts a little more on one connecting rod, detach the cap and the bearing insert with a little more care and then pull out the connecting rod and the remainder of the bearing insert from the crankshaft journal; however it's beneficial to clamp the connecting rod along with the bearing and the cap in a way that the parts don't get mixed up. Perform this process to the other connecting rods, being very cautious not to damage the crankshaft journals with the bolts. Last, wash with solvent not intermingling the parts, then dry until they are thoroughly dry, especially the oil holes.

If the rods and caps are not numbered, you should carefully mark the connecting rods and caps so that they can be reinstalled in the same position on the same crankshaft journal. One common method is to mark the connecting rod and cap at the front of the crankshaft with one dot, the second connecting rod and cap with two dots, and so on.