NUT-HEX 3762454 - Caterpillar

Illustration 1. Typical location of a 128-4786 Tamper Resistant Plug (7/8inch thread) in a governor housing.
Illustration 2. Typical location of a 128-4794 Tamper Resistant Plug (1 5/8inch thread) in a governor housing.The 3208 Machine Engines will have the new 128-7792 and 128-7795 Tamper Resistant Bolts on the AFRC and cover. Illustration 3 shows the locations of the new tamper resistant bolts.
Illustration 3. Locations of the new 128-7792 (1) and 128-7795 (2) Tamper Resistant Bolts on 3208 Machine Engines.The 3304 and 3306 Machine Engines will have new 128-7794 and 128-7796 Tamper Resistant Bolts on the AFRC and cover. Illustration 4 shows the location of the new tamper resistant bolts.
Illustration 4. Location of the new 128-7794 (3) and 128-7796 (4) Tamper Resistant Bolts on 3304 and 3306 Machine Engines.The 3406 Machine Engines with mechanical fuel systems will have new 128-7794 and 128-7796 Tamper Resistant Bolts on the AFRC and cover. Illustration 5 shows the location of the new tamper resistant bolts.
Illustration 5. Location of the new 128-7794 (3) and 128-7796 (4) Tamper Resistant Bolts on 3406 Machine Engines with mechanical fuel systems.The 3408 and 3412 Machine Engines with mechanical fuel systems will have new 128-7793 and 128-7798 Tamper Resistant Bolts on the AFRC and cover. Illustration 6 shows the location of the new tamper resistant bolts. In certain applications, when a dash pot is used, one longer 128-7799 Tamper Resistant Bolt is used in place of the 128-7798 Tamper Resistant Bolt.
Illustration 6. Location of the new 128-7793 (5) and 128-7798 (6) Tamper Resistant Bolts on 3408 and 3412 Machine Engines with mechanical fuel systems. Tamper Resistant Bolt Removal And Installation
If an adjustment is required on a 3208, 3300, or 3400 Engine equipped with tamper resistant bolts, the bolts must be removed. Use the procedure that follows to remove the tamper resistant bolts:
1. Use a 1U-5592 (118 degree) Drill Bit or a 1U-5634 (135 degree split point) Drill Bit to drill a 7/64inch hole in the center of the bolt to be removed.2. Use a 4C-3365 Screw Extractor (5/32-7/32inch), in the hole drilled in Step 1, to remove the bolt.3. When installing a new tamper resistant bolt, tighten the bolt until the bolt head shears off [approximately 12 3 N m (9 2 lb ft) for 1/4inch diameter tamper resistant bolts or 25 6 N m (18 4 lb ft) for 5/16inch diameter tamper resistant bolts].The table identifies the part numbers and sizes of available tamper resistant bolts.