F510 & F525 Cylinder Block – REBORE CYLINDER BLOCK
NOTE: The cylinder block can be rebored to use 0.50 mm (0.020 in.) oversize piston and rings. Have a reliable repair shop rebore the block, or use the drill press and honing tool.
IMPORTANT: The 0.25 or 0.75 mm (0.010 or 0.030 in.) oversize pistons and rings are NOT available as service parts.
1. Rebore cylinder with a honing tool to initial and final bore specifications.
2. Align center of bore to press center. Set the press to operate from 200—250 rpm.
3. Lower and raise hone until ends extend 20—25 mm (0.75—1.0 in.) past ends of cylinder.
4. Turn adjusting nut on one hone until stones contact cylinder wall at narrowest point.
5. Coat inside of cylinder with honing oil. Turn hone by hand. If you cannot turn it, hone is too tight.
6. Start drill press. Move hone up and down in cylinder approximately 20 times per minute.
7. Check cylinder diameter regularly during honing. Stop press before measuring. Remove hone from cylinder.
NOTE: Finish should not be smooth, but have a 40—60 ̊ cross-hatch pattern.
IMPORTANT: Check stone for wear or damage. Use correct stone for the job.
8. Hone the cylinder an additional 0.028—0.030 mm (0.0011—0.0012 in.) for final bore specifications. This allows for 0.020 mm (0.0008 in.) shrinkage when cylinder cools.
IMPORTANT: DO NOT use gasoline or commercial solvents to clean cylinder bores.
Solvents will not remove metal particles produced during honing.
9. Clean the cylinder thoroughly using soap, warm water and clean rags. Continue to clean cylinder until white rags show no discoloration.
10. Dry the cylinder. Apply engine oil to cylinder wall.