DIFFERENTIAL & BEVEL GEAR GP 3668540 - Caterpillar

The bridge dowels must be removed and/or a bridge dowel must be modified when a cylinder head that originally had adjustable bridges is rebuilt.Because of the design of the floating bridge, the cylinder head for a 3500 Engine with EUI and for a 3500B Engine does not require any dowels.Because force is placed on the fuel injector by the rack, the cylinder head for a 3500 MUI Engine requires one 239-0689 Dowel in order to maintain correct orientation of the fuel injector.
Illustration 1 g01023120
(1) 239-0689 Dowel in a cylinder head for a 3500 MUI EngineWhen the cylinder head for a 3500 MUI Engine is rebuilt, only the right hand dowel is installed. The dimension from the surface of the cylinder head to the top of the dowel must not exceed 30 mm (1.2 inch). Use a 239-0689 Dowel for the correct orientation of the 3500 MUI fuel injector.
Illustration 2 g01097665
Typical example of the slotted pocket in the floating valve bridgeWhen viewing the bottom of the new valve bridges the new valve bridges have a pocket on either end for each tip of the valve stem. One of the pockets is round and the other pocket is slotted. The bridge must be placed on the cylinder head so that the round pocket is toward the outside of the engine. Refer to Illustration 3. This orientation of the valve bridge is more stable. This orientation keeps the bridge in position during the initial valve lash adjustment after an engine rebuild.
Illustration 3 g01097686
Orientation of the valve bridge (1) Round pocket (2) Outside of the engineTable 3 lists the effectivity for the new cylinder head groups and assemblies.
Table 3
Effectivity of the New Cylinder Head Groups in 3500 Engines    
3500 Engine with EUI    
Serial Number     Serial Number    
S/N:3LS00228-UP     S/N:3ZW00473-UP    
S/N:3MS00233-UP     S/N:5PS00315-UP    
S/N:3NS00246-UP     S/N:7KM00077-UP    
3500 MUI Engine (Locomotive)    
S/N:2WK00087-UP        
3500 MUI Engine    
S/N:1JZ00603-UP     S/N:67Z02050-UP    
S/N:1KZ01244-UP     S/N:68Z01252-UP    
S/N:1LZ00524-UP     S/N:69Z00889-UP    
S/N:23Z07938-UP     S/N:70Z01077-UP    
S/N:24Z10152-UP     S/N:71Z00403-UP    
S/N:25Z07100-UP     S/N:72Z00567-UP    
S/N:27Z00851-UP     S/N:73Z00968-UP    
S/N:29Z01389-UP     S/N:95Y01216-UP    
S/N:49Y01032-UP     S/N:96Y02060-UP    
S/N:50Y01802-UP     S/N:CTD00183-UP    
S/N:65Z01130-UP     S/N:CTE00333-UP    
S/N:66Z00939-UP     S/N:CTF00263-UP    
S/N:2TS00008-UP     S/N:3HM00015-UP    
S/N:3JS00009-UP     S/N:51Y00861-UP    
S/N:8TL00011-UP     S/N:97Y00742-UP    
S/N:9WN00358-UP     S/N:LPD00005-UP    
3500B Engine    
S/N:1FZ01864-UP     S/N:7SM00910-UP    
S/N:1GZ01498-UP     S/N:8CN00212-UP    
S/N:1NW00145-UP     S/N:8EM00508-UP    
S/N:1PW00427-UP     S/N:8KN00567-UP    
S/N:1TW00347-UP     S/N:8RM00754-UP    
S/N:2AF00364-UP     S/N:9AN00358-UP    
S/N:2BM00186-UP     S/N:AAG00006-UP    
S/N:2EZ00331-UP     S/N:BAG00025-UP    
S/N:2FW00334-UP     S/N:BPX00098-UP    
S/N:2GW00401-UP     S/N:BRC00154-UP    
S/N:2HW00248-UP     S/N:BRN00192-UP    
S/N:2JW00409-UP     S/N:CAN00111-UP    
S/N:3CW00254-UP     S/N:CBB00189-UP    
S/N:3DM00451-UP     S/N:CBN00312-UP    
S/N:3DW00175-UP     S/N:CDE00313-UP    
S/N:3KD00266-UP     S/N:CTA00153-UP    
S/N:4AW00816-UP     S/N:CTB00186-UP    
S/N:4BW00544-UP     S/N:CTC00254-UP    
S/N:4DR00007-UP     S/N:CTD00183-UP    
S/N:4GM00743-UP     S/N:CTE00333-UP    
S/N:4TN00786-UP     S/N:CTF00263-UP    
S/N:5AW00135-UP     S/N:CTG00267-UP    
S/N:6WN00803-UP     S/N:CTH00235-UP    
S/N:7HM00264-UP     S/N:CTJ00200-UP    
S/N:7RN01949-UP     S/N:FFG00018-UP    
S/N:S2X00102-UP     S/N:S2E00102-UP    
S/N:1HZ02430 and 02443-UP        
3500B Engine