SEAL 9D6591 - Caterpillar

Engine: G3412C (S/N: 6ZM1-UP; 8LW1-UP) G3508 (S/N: 4WD1-UP; 2JF1-UP; 9TG1-UP; WPM1-UP; WPN1-UP; DLR1-UP) G3512 (S/N: 4KC1-UP; 5JD1-UP; 7NJ1-UP; WPP1-UP; WPR1-UP; GNS1-UP; 6JW1-UP) G3516 (S/N: 3RC1-UP; 8LD1-UP; 4EK1-UP; WPS1-UP; WPT1-UP; WPW1-UP; 8PW1-UP) G3516B (S/N: CTW1-UP; CEY1-UP; 7EZ1-UP) G3520B (S/N: GLF1-UP; GET1-UP; BGW1-UP)Generator Set: G3406 (S/N: R7E1-UP; KAR1-UP) G3412 (S/N: R7A1-UP; KAP1-UP) G3508 (S/N: CPJ1-UP; CPY1-UP) G3512 (S/N: CRN1-UP; CSP1-UP) G3516 (S/N: ZBA1-UP; ZBB1-UP; ZBC1-UP; CPG1-UP; CSZ1-UP; ZAZ1-UP) G3516B (S/N: CSC1-UP; CME1-UP) G3520B (S/N: CWD1-UP; GZP1-UP)Power Module: PMG3516 (S/N: CFD1-UP)Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Illustration 1 g01358261
(1) Flared end of the union (2) NutThe 7X-7951 Union Elbow may leak on some G3400 Engines and on some G3500 Engines. This problem is due to an error in the machining process. A small leak may occur between flared end of the union (1) and nut (2). All engines have been repaired at the factory. However, there is a small possibility that some of the engines may have been shipped before the problem was corrected.Solution
Inspect the union elbows on the engines that were built between 01December 2006 and 07February 2007. Use a solution of soap and water in order to look for leaks. Perform the following procedures if a leak is detected.
Tighten nut (2) .
Inspect the union for leaks.If the union is leaking proceed to Step 3.
Loosen nut (2) .
Reposition the flared end of the union (1) .
Tighten nut (2) .
Inspect the union for leaks.If the union is leaking proceed to Step 7.
Replace the 7X-7951 Union Elbow .
Inspect the union for leaks.
Table 1
Effective Serial Numbers    
S/N:WWP00175-00175    
S/N:CTW00452-00457    
S/N:CTN00290-00316    
S/N:DLR00100-00100    
S/N:GLF00107-00108    
S/N:GNS00101-00105    
S/N:WPN00125-00155    
S/N:WPP00176-00210    
S/N:WPR00158-00194    
S/N:WPS00123-00124    
S/N:WPT00197-00217    
S/N:WPW00608-00738    
S/N:ZBA00553-00593    
S/N:ZBB00266-00271