MUFFLER 9S7988 - Caterpillar

start by:a) remove cylinder headb) remove precombustion chambers 1. Use tool (A) to put valve spring (2) in compression. Remove locks (1).2. Carefully remove tool (A), the rotocoil, the spring and the valve. Put identification on the valves to tell their locations in the cylinder head. 3. Use tool (B) to check the spring force. The spring force is 57.7 2.9 lb. (257 13 N). The length of the spring under the test force is 1.766 in. (44.86 mm). The free length after the test is 2.05 in. (52.1 mm).4. Do Steps 1 through 3 to the remainder of the valves.Install Valves
1. Put clean engine oil on valve stems. Install valve, spring and rotocoil in the cylinder head. 2. Put tool (A) in position on valve spring and install the locks (1).
Locks can be thrown from valve when compressor is released, if they are not in their correct position on valve stem.
3. Remove tool (A) and hit the top of valve with a plastic hammer to be sure the locks are in their correct position on valve.4. Do Steps 1 through 3 again for remainder of valves.end by:a) install precombustion chambersb) install cylinder head