CORE A 7N3798 - Caterpillar

This Program can only be administeredafter a failure occurs. The decision whether to apply the Program is madeby the dealer. When reporting the repair, use "PS50386" as the Part numberand "7755" as the Group Number. Use "96" as the Warranty Claim DescriptionCode and use "Z" as the SIMS Description Code. The information supplied in this serviceletter may not be valid after the termination date of this program. Donot perform the work outlined in this Service Letter after the terminationdate without first contacting your Caterpillar product analyst.TERMINATION DATE
July 31, 2004PROBLEM
Axial movement of the main pump shaft againstthe 6E1572 shaft seal causes main pump leaks. Main pump leaks due to thiscause will be noticed on the engine flywheel housing.AFFECTED PRODUCT
Model Identification Number
M312 6TL1-1717
M315 7ML1-2740
M318 8AL1-33146ES1-3018SS1-617
M320 6WL1-9089PS1-458PARTS NEEDED
Model PartNumber
M312 2216815Cover Kit
M315/M318 2216816Cover Kit
M320 2216817Cover Kit If dealer stock contains the followingparts, and the main pump shaft has not been damaged by the seal, the sealkits identified in the following table can be exhausted.
Model PartNumber
M312 1943961Seal Kit
M315/M318 1943963Seal Kit
M320 1943964Seal KitACTION REQUIRED
Main Pump leaks can be resolved with the installationof the kit specified for each model. The kit contains components that includenew seals, a new offset cover, and a spring/sleeve that preloads the shaftto prevent axial movement. Please note the attached Rework Procedure.SERVICE CLAIM ALLOWANCES
Product smu/age whichever comes first Caterpillar Dealer Suggested Customer Suggested
Parts Labor Hrs Parts Labor Hrs Parts Labor Hrs
0-6000
0-60 mos 100% * 0 0 0 0
*This is a 5.0?hr job for the M315/M318/M320.This is a 6.0-hr job for the M312.PARTS DISPOSITION
Handle the parts in accordance with your WarrantyBulletin on warranty parts handling.Attach. (1-Rework Procedure)Rework Procedure
Remove swing pump according to the Disassemblyand Assembly manual for each model.
Remove Main Pump according to the Disassemblyand Assembly manual for each model. Set Main Pump on end, with shaft pointingup, to ease serviceability.
Remove shaft snap-ring, seal cover, and shaftseal. (See Fig 1)
Clean the pump shaft in the seal location. Note:If the shaft surface is not free of debris in the seal location, the sealwill not function properly.
Install new o-ring, shaft seal, and seal cover(all supplied in the kit), specified for each model. As seal orientationis critical, note seal orientation detailed below. (Fig. 3)
Re-install shaft snap ring.
Clean pump face, and engine flywheel housing.
Re-install main pump.
Remove snap ring located inside the pump shaftcoupling. Note: Not all couplings will have a snap ring.
Install shaft coupling to main pump shaft.
Insert new bushing (supplied in kit) into shaftcoupling as shown in Fig. 2. Note: If snap ring is not removed in step9, the new bushing cannot be properly installed.
Insert new spring (supplied in kit) into new bushingas shown.
Re-Install swing pump.
Fig 1
Fig 2 Fig 3Seal Orientation Detail The seal will leak if not properlyoriented.