CAMSHAFT 20R1893 - Caterpillar

Valve Spring Replacement Procedure
FT1886 Valve Spring Compressor Group5S1322 Valve Keeper Inserter8S2293 Magnet Assembly1. Remove the valve covers and the rocker shaft assemblies. See the appropriate Service Manual Module.2. Remove the fuel injection nozzle clamp assemblies that hold the fuel injection nozzles in the cylinder heads. See Illustration 2.
Illustration 1. FT1886 Valve Spring Compressor Group.
Illustration 2. Remove fuel nozzle clamps and install the threaded rod from the FT1886 Valve Spring Compressor Group.3. Turn the crankshaft until the cylinder where the valve springs are to be replaced, is at TDC. These cylinders are together at TDC at the same time: 1 and 4, 2 and 5, 3 and 8, 6 and 7.
Do not turn the crankshaft when the locks are removed from the valves. This could allow the valves to fall into the cylinder and make it necessary to remove the cylinder head.
4. Install the threaded rod, part of FT1886 Valve Spring Compressor Group, in the hole where the nozzle clamp assemblies were removed. Make sure the threaded rod is tightened in the hole.5. Put the plate in position on the threaded rod and align it with the valve springs as shown. Install the nut on the threaded rod. Tighten the nut to compress the valve springs. See Illustration 3.
Illustration 3. Install plate and nut from the FT1886 Valve Spring Compressor Group.6. Use the 8S2293 Magnet Assembly to remove the locks from the valve stems. See Illustration 4.
Use a 4 mm open end wrench on the flats of the threaded rod to keep the rod from turning when the nut is loosened. Failure to do this could allow the threaded rod to come out of the nozzle clamp hole and be thrown by the valve spring tension. This could result in serious personal injury.
Illustration 4. Lock removal.7. Use a 4 mm open end wrench on the flats of the threaded rod to keep the rod from turning and turn the nut on the threaded rod counterclockwise until the tension is off the valve springs. Remove the nut and plate. Keep the threaded rod installed.8. Make a replacement of the valve spring seats, valve springs and retainers.9. Again, put the plate in position on the threaded rod and valve springs. Install the nut on the threaded rod. Tighten the nut to compress the valve springs.10. Use the 5S1322 Valve Keeper Inserter to install the locks on the valve stems. See Illustration 5.
Make sure the locks are in their correct position on the valve. The locks can be thrown from the valve when the nut is loosened if the locks are not in their correct position on the valve. This could result in serious personal injury.
11. Use a 4 mm open end wrench on the flats of the threaded rod to keep the rod from turning and turn the nut on the threaded rod counterclockwise until the tension is off the valve springs. Remove the nut, plate and threaded rod.12. Repeat Steps 3 through 11 until all the valve springs have been