CYL AS.-HYD 0R1781 - Caterpillar

Introduction
Disregard the Technical Information Bulletin, TIBU4969-01 18 December, "Thumb Interference with Hammer". Refer to the following information.Problem
Certain custom thumbs experience an interference problem with the H55D S and H65D S hydraulic hammer when the hammer is also mounted on a quick coupler. Solution
Modify the thumb's frame by removing 8 mm (0.32 inch) of material from the outer radius. Refer to illustration 3. Remove the grease zerks and replace the grease zerks with 5M-6214 Pipe Plugs . Replace the stick's pin with a 300-3998 pin .Note: The 300-3998 pin must be ordered from Caterpillar Work Tools. 800-752-2858The affected thumbs can be identified by the thumb's profile. If the thumb has the profile that is shown in illustration 1, then a modification will be required. Illustration 2 shows the profile of a currently produced thumb that does not require a modification. Refer to table 1 for the part numbers of the affected thumbs.
Table 1
Affected Thumbs (1)    
288-4416     281-6681    
291-0532     204-4946    
289-3089     289-2163    
265-5850        
( 1 ) Caterpillar Work Tools Custom Product. 800-752-2858
Illustration 1 g01333769
Profile of old design
Illustration 2 g01333770
Profile of new design
Illustration 3 g01333771
Area to be removed