HOUSING 1W9626 - Caterpillar

966, 966B, 980, 980B And 988 LoadersTwo different control valve body groups (basic) have been used for parts service on the above loaders. The 4J8172 Body Group was originally used on these loaders. This valve was designed to be used in applications where an empty bucket or other attachment is lowered with hydraulic pressure (powered down). In these applications this valve permits faster work cycle times. When this valve is used in applications where a load is lowered, such as when logging forks are used, the valve can cause vibrations in the machine.
The 7J3776 Body Group was later used as a replacement for the 4J8172 Body Group at the factory. The 7J3776 Body Group was designed to be used in applications where the bucket or other attachment is loaded when it is lowered. This valve has slots in the end of the lift stem which permit easy modulation of the valve in the "lower" position. The 7J3776 Body Group will prevent vibration of the machine, but it will also increase work cycle times.
Both the 4J8172 and 7J3776 Body Groups are available for parts service. But, if a complete control valve group is ordered for parts service, the 7J3776 Body Group will be part of the control valve group. If a complete control valve group is needed, but with a 4J8172 Body Group, the 4J8172 Body Group and all the parts which are needed to make a complete control valve group must be ordered separately.