CYLINDER GP-BOOM 2898093 - Caterpillar

Caterpillar: Confidential Yellow
PRIORITY:TIGHTEN ENGINE OIL LINE CONNECTION IF NEEDED - 627B TRACTORS - PI3028 WORLDWIDE EXCEPT BRAZIL
  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.
TIGHTEN ENGINE OIL LINE CONNECTION IF NEEDED, 627B Tractors, 1307, 1378, PI3028 U-77 A-70 AU-64 C-71 E-62 O-59 PRIORITY Problem On 627B Tractors, the remote oil filter is connected by oil lines to an adapter fastened to a base on the engine. The adapter, see Illustration, is fastened to the base with a special hollow stud (2P4315). On some tractors, this stud is not installed far enough into the base on the engine. This will cause the stud and adapter to separate from the base on the engine, resulting in a sudden loss of oil. Affected 627B Tractors All 627B Tractors, 14S1080-14S1174 and 15S1551-15S1593, are included in this Program. No new parts are needed. Action Requested Many of these same tractors have scrapers needing a new spring in the scraper governor rotochamber. Do both during the same trip. See September 7, 1983 Service Letter, SAFETY PI1008. Also, do PRIORITY PIP434 in April 4, 1983 Service Letter if not yet done. First, inspect the oil line connection to see if retightening is necessary: 1. Remove engine access door in the cab. 2. Using a mirror, count the number of exposed-threads on the adapter stud (2P4315). Any exposed threads will be visible between the stud retaining nut and the connector for the hose. See Illustration. If you can see more than 1 1/2 threads showing, the stud must be retightened. If 1 1/2 or less threads are showing, no further work is needed. (SEE ILLUSTRATION) If necessary to retighten the adapter stud: 1. Remove the engine breather tube by working through the access hole in the cab. 2. Install a chain hoist (come-along) to support the crankcase guard, remove guard bolts, and lower the front of the guard halfway to the ground. 3. Disconnect the filter oil line hose coupling nut from the connector which is installed inside the lower end of the adapter stud. Hold the connector with a wrench to prevent it from backing out of the threads inside the stud. 4. Remove the connector from the stud to allow use of a 2 1/4" socket to loosen the jamnut on the stud. Back the nut off about two to three threads. 5. Install a reducer bushing, such as 9B3523 Bushing, with hexagonal head in the 3/4-14 NPTF pipe threads in the bottom of the stud. This provides a method to tighten the stud into the base above the adapter. 6. Tighten the stud by turning on the bushing until you obtain 68 +/- 14 N X m (50