HOSE 1386979 - Caterpillar

When using the stud tensioning cylinder, the pressure gauge readings must be carefully monitored by the operator at all times. If the pressure reading does not rise, even while continually applying pressure, stop immediately. This symptom may indicate warping or deformation of the stud. If this problem occurs, it is essential to release all pressure, remove the stud tensioning cylinder, and check the shape and dimensional accuracy of the stud and joint.
The bolt-tensioning cylinders must never exceed their maximum stroke. In the case of the cylinders covered by this Tool Operating Manual, this is 10 mm. When the maximum stroke is achieved, a red mark is visible on the change bushing. Do not proceed further in applying pressure to the cylinder as an over-stroke situation will occur. Further extension will compress the return springs to the point of destruction. In some cases, the cover will pop loose. If the bolt-tensioning cylinder is operated above its maximum stroke, it is no longer capable of functioning and requires repair.
If the stud tensioning cylinder is operated above the maximum stroke, it will no longer function.
Illustration 14 g02987976
Once the desired tension has been reached and the nut is tightened into position on the stud, turn the motor/pump unit OFF.
Do not unhook the high-pressure hoses until the piston is fully retracted (bushing is flush with top of cylinder) and all hydraulic pressure is released.
Store the stud tensioning tool group in a dry climatized storage area.
The C175 Main Bearing Stud Tensioner Cylinders 253-3272, have a defined service life of 2000 tension cycles, after which the change bushing within the tensioner cylinder must be replaced.
Pressure Settings
Pumps with Pressure Limiting Valves (Electric and Pneumatic)
Disconnect the stud tensioning cylinder from the motor/pump unit, if attached.
Close the stop valve.
Turn the motor/pump unit ON using the safety toggle switch.
Screw the pressure limit valve inward or outward until the desired pressure is obtained. Do not exceed the maximum pressure rating for the unit.
Turn the motor/pump unit OFF.
Open the stop valve.Pumps without Pressure Limiting Valves (Manual)
Install the stud tensioning cylinder onto the stud. Make sure that the bottom of the cylinder is against the supporting surface of the engine.
Connect the manual stud tensioning pump to the high-pressure hose.
Close the stop valve.
Pump the unit until the desired pressure is reached. Do not exceed the maximum pressure rating for the unit.Maintenance Section
Replacing the Seals in Cylinder Groups
Illustration 15 g02988069
Illustration 16 g02988298
Table 9
Nomenclature for the Stud Tensioner    
1     Cylinder    
2     Piston    
3     Bushing    
4     Cover    
5     High-Pressure Coupler    
6     Hydraulic Manifold    
7     Steel/Rubber Seal    
8     O-ring Seal (not visible)    
9     Piston Backup Ring    
10     Piston Seal    
11     Cylinder Backup Ring    
12     Cylinder Seal    
Clamp stud tensioning cylinder (1) into a vice with copper jaws.
Remove cover (4) with a spanner wrench.
Note the order and position of the spring plates on the bushing. Remove and save the spring plates (not shown).
Remove high-pressure coupler (5)