SPROCKET COVER AND CASE CHANGE OIL LEAK/325-4L TRANSMISSION

BEGINNING SEPTEMBER 1982, THE THM 325-4L TRANSMISSION WILL BE BUILT USING A NEW DESIGN CASE (FIGURE #1) AND SPROCKET COVER (FIGURE #2). THIS NEW DESIGN INVOLVES THE ADDITION OF TWO TAPPED HOLES TO THE CASE AND TWO BOLT HOLES TO THE SPROCKET COVER, WHICH WILL REDUCE OIL LEAKS FROM THE SPROCKET COVER CORNERS. PRIOR TO THIS CHANGE THERE WAS AN INTERIM DESIGN WHERE ONLY ONE BOLT HOLE (FIGURE #1 & 2 BOLT HOLE #1) WAS DRILLED THROUGH THE SPROCKET COVER AND CASE. WITH THIS INTERIM DESIGN, EFFECTIVE IN MAY, 1982, A BOLT, FLAT WASHER, LOCK WASHER AND NUT WAS USED TO HOLD THE COVER TO THE CASE IN THIS LOCATION. IF EARLY 1982 MODEL 325-4L TRANSMISSIONS WITHOUT THE INTERIM DESIGN BOLT HOLE, SHOULD HAVE TO BE UPDATED TO ELIMINATE OIL LEAKS IN THIS CORNER OF THE SPROCKET COVER, REFER TO THE FOLLOWING SERVICE PROCEDURE. SERVICE PROCEDURE 1.INSPECT THE SPROCKET COVER FOR CRACKS. REPLACE IF NECESSARY. 2.DRILL A 7MM (.250 IN) HOLE THROUGH THE COVER AND CASE LIP. (FIGURE 1 & 2 BOLT HOLE #1). 3.INSTALL A BOLT (PART NO. 11503869) THROUGH A FLAT WASHER (PART NO. 11500322) AND INSTALL THEM INTO THE SPROCKET COVER AND CASE. (FIGURE 1 & 2, BOLT HOLE #1). ADD THE LOCK WASHER (PART NO. 9439510) AND NUT (PART NO. 11507095) TO THE OTHER SIDE OF THE CASE LIP AND TORQUE THE BOLT TO 13 N.M (9FT. LBS.) MAXIMUM. 4.IF THE LEAK IS NOT CORRECTED, THE SPROCKET COVER MUST BE REMOVED, AND RE-SEALED WITH R.T.V. FOLLOW THE REMOVAL AND APPLICATION PROCEDURES OUTLINED IN THE SERVICE MANUALS. NOTICE: EXCESSIVE AMOUNTS OF R.T.V. WHEN APPLIED TO THE CASE FLANGE MAY BLOCK OFF THE TRANSMISSION AIR VENT, 3RD. ACCUMULATOR AIR FEED, SEAL DRAIN AND/OR THE DRAINBACK HOLES IN THE BOTTOM OF THE CASE.

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