HYDRAULIC AR 4490328 - Caterpillar

Installation of the Updated Elbow Assemblies on Machines with the High Altitude Arrangement
Table 2
Parts Needed to Update the 172-4336 Exhaust Pipe Gp .    
Item     Qty     Part Number     Description    
1     1     253-6176     Elbow As    
2     1     253-6177     Elbow As    
3     2     7E-8452     Clamps    
Illustration 3 g01413472
Illustration 4 g01413474
Remove the two 7E-8452 Clamps (6) from the 253-6176 Elbow As (4) and the 253-6177 Elbow As (5) .
Remove the 233-7711 Heat Shield (10) and the 241-8492 Band Clamp (11) from the 253-6176 Elbow As (4) .
Remove the 233-7711 Heat Shield (10) and the 241-8492 Band Clamp (11) from the 253-6177 Elbow As (5) .
Remove the six 8T-4192 Bolts (8), the six 8T-4223 Hard Washers (9) and the two 154-6351 Straps (7) from the elbow assemblies.
With a suitable lifting device, remove the 253-6176 Elbow As (4) and the 253-6177 Elbow As (5) from the machine.
Inspect the flange faces and the tubes on the end of the mufflers that are toward the elbow assemblies for damage. If you find damage to the flange faces or the tubes of the mufflers, replace the mufflers.
By using a suitable lifting device, install the updated 253-6176 Elbow As (1). Secure the elbow assembly with the 241-8492 Clamp (11) that was removed in Step 2. Leave the clamp loose so you can adjust the parts. Install one new 7E-8452 Clamp (3) to the elbow assembly and the muffler assembly. Leave the clamp loose so you can adjust the parts.
By using a suitable lifting device, install the updated 253-6177 Elbow As (2) to the rear exhaust tube. Secure the elbow assembly with the 241-8492 Band Clamp that was removed in Step 3. Leave the clamp loose so you can adjust the parts. Install one new 7E-8452 Clamp (3) to the elbow assembly and the muffler assembly. Leave the clamp loose so you can adjust the parts.
Tighten the 241-8492 Band Clamp (11) to 11 N m (97 lb in).
Tighten the two 7E-8452 Clamps (3) to 16 4 N m (12 3 lb ft). Tap lightly around the circumference of the two clamps. Then, tighten the three clamps to 16 4 N m (12 3 lb ft).Note: The static inspection torque should be no less than 9 N m (80 lb in).
Install the two 233-7711 Heat Shields (10) that were removed in Step 2 and Step 3 to the updated 253-6176 Elbow As (1) and to the 253-6177 Elbow As (2) .