38374A 1 Mercury SHIM, BEARING CUP TO GEAR HOUSING (.002-3-4-10)

Never use water alone without Supplemental Coolant Additives (SCA) or without inhibited coolant. Water alone is corrosive at engine operating temperatures. Water alone does not provide adequate protection against boiling or freezing.
Note: Premix the coolant solution in order to provide protection to the lowest ambient temperature that is expected.Note: Pure undiluted antifreeze freezes at −23 °C (−9 °F).In engine cooling systems that use water alone, Caterpillar recommends the use of SCA. SCA helps to prevent the following conditions from occurring:
Corrosion
Formation of mineral deposits
Cavitation erosion of the cylinder liner
Foaming of the coolantIf Caterpillar SCA is not used, select a commercial SCA. The commercial SCA must provide a minimum of 2400 mg/L or 2400 ppm (140 grains/US gal) of nitrites in the final coolant mixture.The quality of the water is a very important factor in this type of cooling system. Distilled water or deionized water is recommended for use in cooling systems. If distilled water or deionized water is not available, use water that meets the minimum requirements that are listed in the table for recommended water properties in this publication, "General Coolant Information" topic (Maintenance Section).A cooling system that uses a mixture of SCA and water only needs more SCA than a cooling system that uses a mixture of glycol and water. The SCA concentration in a cooling system that uses SCA and water should be six to eight percent by volume. Refer to Table 1 for the amount of SCA that is required for various capacities of the cooling system.
Table 1
Caterpillar SCA Requirements for SCA and Water Cooling Systems
Cooling System Capacity Caterpillar SCA at Initial Fill Caterpillar SCA at 250 Hours
22 to 30 L (6 to 8 US gal) 1.75 L (64 fl oz) 0.44 L (15 fl oz)
31 to 38 L (9 to 10 US gal) 2.30 L (80 fl oz) 0.57 L (20 fl oz)
39 to 49 L (11 to 13 US gal) 3.00 L (100 fl oz) 0.75 L (25 fl oz)
50 to 64 L (14 to 17 US gal) 3.90 L (128 fl oz) 0.95 L (32 fl oz)
65 to 83 L (18 to 22 US gal) 5.00 L (168 fl oz) 1.25 L (42 fl oz)
84 to 110 L (23 to 29 US gal) 6.60 L (224 fl oz) 1.65 L (56 fl oz)
111 to 145 L (30 to 38 US gal) 8.75 L (296 fl oz) 2.19 L (74 fl oz)
146 to 190 L (39 to 50 US gal) 11.50 L (392 fl oz) 2.88 L (98 fl oz)
191 to 250 L (51 to 66 US gal) 15.00 L (512 fl oz) 3.75 L (128 fl oz) Refer to Table 2 for part numbers and for quantities of SCA.
Table 2
Caterpillar Liquid SCA
Part Number Quantity
6V-3542 0.24 L (8 oz)
111-2372 0.36 L (12 oz)
8T-1589 0.47 L (16 oz)
3P-2044 0.94 L (32 oz)
8C-3680 19 L (5 US gal)
5P-2907 208 L (55 US gal) Maintain the SCA in the same way as you would maintain a cooling system that uses heavy-duty coolant/antifreeze. Adjust the maintenance for the amount of SCA additions. See Table 1 for the amount of SCA that is required.Cooling Systems with Larger Capacities
Adding the SCA to Water at the Initial Fill
Use the equation that is in Table 3 to determine the amount of Caterpillar SCA that is required at the initial fill. This equation is for a mixture of only SCA and water.
Table 3
Equation For Adding The SCA To Water At The Initial Fill
V × 0.07 = X
V is the total volume of the cooling system.
X is the amount of SCA that is required. Table 4 is an example for using the equation that is in Table 3.
Table 4
Example Of The Equation For Adding The SCA To Water At The Initial Fill
Total Volume of the Cooling System (V) Multiplication Factor Amount of SCA that is Required (X)
946 L
(250 US gal) × 0.07 66 L
(18 US gal) Adding the SCA to Water for Maintenance
For the recommended service interval, refer to the Operation and Maintenance Manual, "Maintenance Interval Schedule" for your engine.Use the 8T-5296 Coolant Conditioner Test Kit to test the concentration of SCA. Make the following modifications to Steps 3 and 5 of the 8T-5296 Coolant Conditioner Test Kit instructions:STEP 3 - Add tap water to the vial up to the "20 ml" mark.STEP 5 - When the defined procedure is used, a concentration of six to eight percent will yield between 20 drops and 27 drops. If the number of drops is below 20 drops,