16400-ZY6-003 Honda BODY ASSY., THROTTLE (Honda Code 7633605).

2. Turn the crankshaft until two of the pistons are at bottom center. Remove the nuts and bolts (1) from the connecting rods that are at bottom center. Remove connecting rod caps (2), and put identification marks on them for installation purposes.
Do not let the connecting rods hit the crankshaft or the bottom edge of the cylinder liners when the pistons are removed.
3. Push the connecting rods and pistons away from the crankshaft until the piston rings are out of the cylinder liners. Remove the two pistons from the engine.4. Keep each connecting rod cap with its respective connecting rod and piston. Put identification marks on each piston as to its location in the engine.5. Do Steps 1 through 4 for the removal of the remaining pistons.Install Pistons And Connecting Rods
1. Turn the crankshaft until the bearing journals for the pistons to be installed are at bottom center.2. Put clean engine oil on the crankshaft journals and on the inside of the cylinder liners. Put clean engine oil on the piston rings and the connecting rod bearings.3. Move the piston rings on the pistons until the ring openings are approximately 90° apart. 4. Put the piston in the cylinder liner with the "V" mark on the piston in alignment with the "V" mark on the cylinder block. Put tooling (A) in position on the cylinder block and compress the piston rings.5. Push the piston into the cylinder liner and out of the ring compressor. 6. Pull the connecting rod into position on the crankshaft as shown. Install connecting rod bolts (1) in the connecting rods.7. Put clean engine oil on the lower half of the connecting rod bearing. Put 2P2506 Thread Lubricant on the bolt threads and on the surfaces of the nuts that make contact with the connecting rod caps.
When the connecting rod caps are installed, make sure the number on the side of the cap is next to, and respective with, the number on the side of the connecting rod.
8. Install connecting rod caps (2) and the nuts that hold them. Tighten the nuts to a torque of 40 4 N m (30 3 lb ft). Put a mark on each nut as to its location, and tighten them 90° more.9. Do Steps 1 through 8 for the remainder of the pistons.End By:a. install oil pumpb. install cylinder head assemblyDisassemble Pistons and Connecting Rods
Start By:a. remove pistons and connecting rods 1. Remove the rings from the pistons with tool (A). 2. Remove retaining ring (3), piston pin (1) and connecting rod (2) from the piston.3. Clean the piston ring grooves on the old piston with an acceptable ring groove tool.4. See, Use Of Piston Pin Bearing Removal And Installation Tools, Special Instruction, Form No. SMHS7295, for more information about removal and installation of piston pin bearings. Be sure to remove the bearings from the crankshaft end of connecting rod.5. Heat the connecting rod in an oven to a temperature of 177° to 260° C (350° to 500° F). Never use a direct flame to heat a connecting rod. 6. Put 6V3029 Spacer (11) in the base plate. Put the connecting rod on the base plate of tooling (B).7. Put the connecting rod piston pin bearing end in the center of the port assembly of tooling (B). Install pin (6) in the center of the bore of the connecting rod bearing.8. Install 6V2049 Adapter (9). Put the hole in the adapter in alignment with the hole in the base plate of tooling (B).9. Install clamp bar (10) and clamp pin (7). The old bearing is pushed out by tooling (B) as the new bearing is installed.10. Put 5P8645 Pusher Adapter (8) in position, as shown, with the taper side down. The piston pin bearing joint must be in alignment with the hole in adapter (9) and the base plate of tooling (B).11. Put pusher (4) on adapter (8).12. Use tooling (B) to push the new piston pin bearing (5) into the connecting rod until adapter (8) of tooling (B) makes full contact with the connecting rod surface.13. Remove the connecting rod and the old piston pin bearing from tooling (B).14. Check the piston pin bearing bore diameter after the bearing is installed. The correct dimension is 43.210 0.008 mm (1.7012 .0003 in.). The maximum permissible clearance between the bearing and piston pin (worn) must not be more than 0.08 mm (.003 in.).Assemble Pistons And Connecting Rods
1. Install connecting rod (2) in the piston with the bearing tab groove (slot) (12) on the same side as the cutout (depression) (13) on the head of the piston.2. Install piston pin (1) and retaining rings (3) in the piston.3. When old pistons are to be used, clean the piston grooves with an acceptable piston groove cleaning tool. 4. Install the spring for the oil ring. Install the oil ring with tool (A). The gap in the ring must be approximately 180° from the ring spring connections.5. The two compression rings have marks "UP-1" and "UP-2". The rings must be installed with these marks toward the top of the piston with "UP-1" as the top ring. After installation of all three piston rings, put piston rings in position so the gaps in rings are 120° apart. Compression rings that do not have identification can be installed either way.6. To check the clearance between the piston ring grooves and rings, see the Engine Specifications Manual.7. See the Engine Specifications Manual to check the clearance between the ends of the piston rings (end gap).End By:a. install pistons and connecting rods