Usage:
768C, 772B, 776, 834B Tractors;
769C, 773B, 777 Trucks;
992C Loaders ( 42X, 49Z1-397, 49Z399)
Reference: "New Oil Cooler Core Can Be Removed For Field Service," Service Magazine, April 18, 1983, page 2. If leakage occurs on a removable core oil cooler, the following checks should be made before the oil cooler or core is replaced.
1. Check to make sure the correct gasket has been installed between the cooler bonnet and the cooler shell, see Illustration 1. On 773B Trucks (63W844-Up) this gasket may be missing. If a new gasket is needed, after disassembly and testing, use the new 4W338 Gasket. Do not use the former 7S8767 Gasket that was used with the former cooler core. The bolt pattern is the same for both gaskets. The new 4W338 Gasket has a smaller [160 ± 0.5 mm (6.3 ± .02") diameter] center hole than the former gasket. The smaller center hole makes sure there is proper loading of the flange end of the cooler core.
Illustration 1. Location of oil cooler gasket.
2. Do an air pressure test. Install the 7S8768 Adapter (used only for shipment and test) on the shell assembly end that has only one O-ring seal. This prevents a pressure loss at the seal and keeps the tube bundle inside the shell during the test. Block off the two oil inlets with tooling as shown in Illustrations 2 and 3. Suggested dealer fabricated tooling for testing oil coolers: 2 - 406 mm (16") C-clamps, 2 - 25.4 mm (1.00") × 25.4 mm (1.00") × 76.2 mm (3.00") V-blocks, 1 - 25.4 mm (1.00") × 76.2 mm (3.00") diameter block with a 90° through hole and quick disconnect fitting. Use other fittings as needed to supply air pressure. Test the cooler core with air pressure. Use 620 kPa to 830 kPa (90 to 120 psi) air pressure for testing.
Illustration 2. Testing for leaks.
If leakage is found, the tube bundle can be removed using the fabricated tooling shown in Illustration 4 along with the procedure that follows:
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Use caution so as not to damage the tubes or flange of the bundle assembly after its removal.
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Illustration 3. Tooling to be fabricated.
Illustration 4. Fabricated tool components.
To use the fabricated tool, put the shell assembly on its side. Use two 1/2" - 13 by 38 mm (1.5") long bolts to fasten the tool to the end of the cooler (opposite the flange end). Slowly tighten the bolts. The force will push the tube bundle assembly out the other end of the shell assembly.
To install the tube bundle in the shell, use the procedure that follows:
1. Install new O-ring seals in the shell assembly.
2. Put a small amount of the system lubricant on the end of the tube bundle assembly that makes contact with the O-rings in the shell assembly.
3. Install the tube bundle assembly in the shell assembly so that the 4 mm (.16") hole in the end of the bundle assembly is in position over the pin in the face of the shell assembly.