Piston: Service and Repair

REMOVAL
1. Cylinder head from the cylinder block.
2. Engine oil pan and oil pump strainer.
3. Mark cylinder number on each piston, connecting rod and connecting rod bearing cap.
4. Eight nuts and connecting rod bearing caps.





5. Slide hose piece over connecting rod studs to prevent damage to the cylinder when piston and connecting rod are removed.
^ Clean the carbon from top of cylinder bore.
6. Piston and connecting rod from cylinder bore by pushing out through the top of the cylinder bore.

INSTALLATION
^ Tool Required:
- J 8037 Piston Ring Compressor, Or Equivalent

NOTE:
^ Two sizes of pistons are available as standard size replacement parts ensuring proper piston-to-cylinder clearance.
^ When installing a standard size piston, make sure to match each piston with a cylinder as follows:

1. Apply light coat of clean engine oil to pistons, rings, cylinder walls, connecting rod bearings and crank pins.
2. Guide hoses over the connecting rod bolts to prevent damage to bearing journal and connecting rod bolt threads when installing connecting rods.
3. Piston and connecting rod into cylinder bore using a piston ring compressor, ensuring arrow mark on top of the piston points to crankshaft pulley end. Use a hammer handle to tap piston head and install piston into cylinder bore, keeping piston ring compressor pressed securely against the top of the cylinder block until all piston rings have entered cylinder bore.





A. Each piston has a stamped number 1 or 2. These numbers represent the outer diameter of the piston.





B. There are also stamped numbers 1 or 2 on the cylinder block. The first number indicates the inner diameter of the No. 1 cylinder, the second number, the No. 2 cylinder, the third number, the No. 3 cylinder, and the fourth number, the No. 4 cylinder.





C. The stamped numbers on the pistons must correspond with the numbers stamped on the cylinder block for the stamped piston and cylinder number diameter specifications.
4. Remove hose pieces from connecting rod bolts.
5. Connecting rod bearing cap to connecting rod; secure with two nuts.

NOTE: Be sure to point arrow mark on cap toward the crankshaft pulley side.

^ Tighten the connecting rod bearing cap nuts to 35 Nm (26 ft. lbs.).
6. Engine oil pan and oil pump strainer.
7. Cylinder head to the cylinder block.