HOUSING 2211831 - Caterpillar

Caterpillar: Confidential Yellow
FURTHER IMPROVEMENTS MADE TO ENGINE OIL COOLER AND OIL PUMP BYPASS VALVE AVAILABLE - 992C LOADERS (42X, 49Z) - PI7104 - MAI LED WORLDWIDE EXCEPT BRAZIL, CFEL, AMERICAS, COSA
  The information supplied in this service letter may not be valid after the termination date of this program.   Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.
FURTHER IMPROVEMENTS MADE TO ENGINE OIL COOLER; NEW COOLER AND OIL PUMP BYPASS VALVE AVAILABLE, 992C Loaders (42X, 49Z), 1315, 1350, 1378, PI7104 U-64 A-42.1 AU-55 C-59 E-40.1 SEE SEPTEMBER 25, 1984 optional Add a reference NOTE to your copies of the March 30, 1984 (PI7091) and April 3, 1984 (PI7067) Service Letters. It is convenient to do this new PIP at the same time. Also, remove 992C Loaders from the May 14, 1982 Service Letter, SLA122. Problem The engine oil cooler core on 992C Loaders is not providing expected service life in some cases. Failures of the present core can contaminate the cooling system or the engine lubrication system. New cooler cores have rubber end sheets to support the tube bundle. These end sheets take the place of the former brazed end sheets. The new cores are now used in production. Also, a dampened engine oil pump bypass valve is used with the rubber end sheet cooler. The dampened valve reduces pressure surges in the lubrication system which can contribute to short cooler life. A new 7W2356 Pump Grp. is used in production. Affected Loaders and Parts Needed 42X1-up * 49Z1-up * Includes those on which 1W7406 Core Assembly installed per May 14, 1982 Service Letter, SLA122. New parts needed are: Oil Cooler Parts Oil Pump Bypass Valve Parts 1 - 4W6045 Core As. (engine) 2 - 4F7387 Seal 1 - 5F0149 Ring 1 - 4N0864 Gasket 1 - 4W0338 Gasket 3 - 6L1651 Seal 1 - 9M7002 Seal 1 - 7W2358 Spring 1 - 7W2357 Guide * 1 - 4N1151 Gasket (oil pan) ** 1 - 6N1931 Plunger * Not needed if bypass valve parts are installed per PI7091. ** Install new plunger only if former plunger shows signs of scuffing. Action Requested The new oil cooler core and bypass valve parts for the engine oil pump can be installed on all the listed loaders. If you install the new core, update the pump bypass valve at the same time. However, before installing the new bypass valve parts, check for the letter "D" stamped on the block next to the engine serial number plate. If this letter is present, the new valve parts are already installed and only the new cooler core is needed. When to install the new parts-- When the oil pan is removed for any reason, install the bypass valve parts even if the new engine oil cooler core is not being installed. For example, if new rod and main bearings are installed (March