74 SEBU7899-05 Maintenance Section Crankshaft Vibration Damper - Inspect NOTICE Use Only Approved SCAs . Conventional coolants require the maintenance addition of SCA throughout their expected life. Do NOT use an SCA with a coolant unless specifically approved by the coolant supplier for use with their coolant. It is the responsibility of the coolant manufacturer to ensure compatibility and ac- ceptable performance. 5. Clean the cooling system filler cap. Install the cooling system filler cap. For further information, refer to Special Publication, SEBU6251, “Cat Commercial Diesel Engine Fluids Recommendations”.
i02933380 Crankshaft Vibration Damper - Inspect Failure to follow the recommendations can result in shortened cooling system component life. NOTICE Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, test- ing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any com- ponent containing fluids. SMCS Code: 1205-040 Damage to the crankshaft vibration damper or failure of the crankshaft vibration damper can increase torsional vibrations. This can result in damage to the crankshaft and to other engine components.
A damper that is damaged can cause excessive gear train noise at variable points in the speed range. Refer to Special Publication, NENG2500, “Cat Deal- er Service Tool Catalog” and to Special Publication, GECJ0003, “Cat Shop Supplies and Tools” for tools and supplies suitable to collect and contain fluids on Cat products. The damper is mounted to the crankshaft which is located behind the belt guard on the front of the engine. Visconic Damper Dispose of all fluids according to applicable regula- tions and mandates. The visconic damper has a weight that is located inside a fluid filled case. The weight moves in the case in order to limit torsional vibration. Note:
Caterpillar recommends that an S·O·S Coolant Analysis (Level 1) be performed to check the concentration of SCA. Inspect the damper for evidence of fluid leaks. If a fluid leak is found, determine the type of fluid. The fluid in the damper is silicone. Silicone has the following characteristics: transparent, viscous, smooth, and adhering. Maintain the Proper Concentration of SCA in the Coolant If the fluid leak is oil, inspect the crankshaft seals for leaks. If a leak is observed, replace the crankshaft seals. Pressurized System: Hot coolant can cause seri- ous burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool.
Loosen the cooling system pressure cap slowly in order to relieve the pres- sure. Inspect the damper and repair or replace the damper for any of the following reasons: The damper is dented, cracked, or leaking. The paint on the damper is discolored from heat. 1. Remove the cooling system filler cap slowly. The engine has had a failure because of a broken crankshaft. 2. Test the concentration of the SCA with a 286-2578 Nitrite Test Strip or review the results of the S·O·S Coolant Analysis (Level 1). Analysis of the oil has revealed that the front main bearing is badly worn. 3. If necessary, drain some coolant in order to allow space for the addition of the SCA.
There is a large amount of gear train wear that is not caused by a lack of oil. 4. Add the amount of SCA required to maintain a concentration of 3 percent to 6 percent SCA in the coolant.