Temporarily install the
Crankshaft pulley bolt in the crankshaft front end to enable turning of the crankshaft and check for a wear ridge at the top of each cylinder; if present, it must be machined out before removing the pistons, using a ridge reamer to eliminate the raised material. Remove the plugs from the four service holes with an Allen wrench to access the piston pin cir clips, soaking them with penetrating oil if they are difficult to remove, and ensuring the wrench is fully inserted to avoid rounding off the hexagonal opening. Position the piston at bottom dead center by turning the crankshaft, then use needle-nose pliers through the service holes to remove the cir clips, utilizing a small flashlight to ensure proper alignment. For piston pin removal, a special tool is required to extract the pins through the service hole, which can be fabricated from steel rod; if the pins are varnished, a slide hammer or striking the tool may be necessary. Keep the pistons and pins together, marking the pistons for reinstallation in their original locations. The pistons can remain in the cylinder bores until the crankcase is separated, at which point they can be driven out with a wooden or plastic hammer handle, or they can be removed beforehand by turning the crankshaft slowly until the connecting rods push the pistons out slightly, inserting cleaned and oiled piston pins into the connecting rods through the service holes, and then turning the crankshaft until the pin pushes the piston from the bore before pulling the pistons out.