CONTROL GP-SERVICE BRAKE 2V4227 - Caterpillar

280 kW (375 hp) And 317 kW (425 hp) 3208 ( 1Z ) Marine Engines So EquippedSUPPLEMENT: 03/05/90SERVICE MAGAZINE; OCTOBER 30, 1989; PAGE 12; "New MG507 And MG507A Marine Gear Groups; New Marine Transmission Mounting Group" for All 280 kW (375 hp) And 317 kW (425 hp) 3208 (1Z) Marine Engines So Equipped.Change footnote1 to read "For MG507A," and footnote2 to read "For MG507".--------------- END SUPPLEMENT ---------------Description of Change: New MG507 and MG507A Marine Gear Groups are available for use on new 425 hp 3208 Engines and earlier 375 hp 3208 Engines. The three input gears of these marine transmissions now are shot-peened to improve the strength of the gears and the input shaft is splined instead of tapered due to the new coupling assembly. New marine transmission mounting groups are used with the new MG507 and MG507A Marine Gear Groups. The mounting group has a new coupling assembly that is used between the engine and transmission. The new coupling assembly reduces the torsional loads on the input shaft gear teeth.
These changes were made to correct field failures of input gears on 375 hp 3208 Engines and is required on all 425 hp 3208 Engines. The new coupling assembly is also effective in correcting low speed (low idle) noise complaints.
Adaptable To: The new marine gear groups identified in Chart A are to be used on all 425 hp 3208 Engines. The new marine gear groups can be used on 375 hp 3208 Engines that have input gear failures. The new 7E5480 or 7E5481 Marine Transmission Mounting Group must be used with the new marine gear groups. Earlier MG507 and MG507A Marine Gear Groups can be updated if the following components in Chart B are all used together and 3T2428 Bearing Support is reworked as shown in Illustration 3. See Illustrations 1 and 2.
Illustration 1. Location of components in marine transmission mounting group.
Illustration 2. Location of components in marine gear group - MG507 shown.
Illustration 3. Rework dimension for bearing support.