Disassemble Pistons


a) remove pistons

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. Remove the bearings from the crankshaft end of the connecting rod.

4. See USE OF PISTON PIN BEARING REMOVAL AND INSTALLATION TOOLS, SPECIAL INSTRUCTIONS, Form No. SMHS7295-02 for more information about removal and installation of piston pin bearings.

5. Heat the connecting rod in an oven to a temperature of 350°-500°F (177°-260°C). 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 for 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).

NOTE: 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 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 1.7012 ± 0.00030 in. (43.210 ± 0.0076 mm). The maximum permissible clearance between the bearing and piston pin (worn) must not be more than .003 in. (0.08 mm).

Assemble Pistons

1. When old pistons are used, clean the piston grooves with an acceptable ring groove tool.

2. Install the connecting rod bearings in the crankshaft end of the connecting rod. Make sure the tabs in the back of the bearings are in the tab grooves of the connecting rod and cap.

3. Put connecting rod (2) in position in the piston with bearing tab groove (3) and number identification on the same side as the “V” mark on the top of the piston.

4. Install piston pin (1) and retaining ring (4).

5. For correct piston and ring clearances, see PISTONS AND RINGS in SPECIFICATIONS.

6. Install the oil ring spring in the oil ring groove of the piston.

NOTE: The oil ring must be installed on the piston with the ring end gap 180° from the oil ring spring joint.

7. Install the oil ring on the piston with tool (A).

8. Install the intermediate piston ring with the side that has the mark “UP-2” toward the top of the piston with tool (A).

9. Install the top piston ring with the side that has the mark “UP-1” toward the top of the piston. Make sure piston ring end gaps are 90° apart before the pistons are installed.


a) install pistons

Posted in D6Tagged