OIL PRESSURE CHART RELEASE INFORMATION

THIS BULLETIN CONTAINS AN UPDATED "PRELIMINARY CHECK PROCEDURE" (OIL PRESSURE CHART). ILLUSTRATION ON BACK OF THIS BULLETIN. PLEASE USE THE ATTACHED CHART TO UPDATE YOUR 1981 BUICK CHASSIS SERVICE MANUAL, PAGE 7A6-3. PRELIMINARY CHECK PROCEDURE CHECK TRANSMISSION OIL LEVEL CHECK AND ADJUST T.V. CABLE CHECK OUTSIDE MANUAL LINKAGE AND CORRECT CHECK ENGINE TUNE INSTALL OIL PRESSURE GAGE CONNECT TACHOMETER TO ENGINE CHECK OIL PRESSURES IN THE FOLLOWING MANNER: MINIMUM T.V. LINE PRESSURE CHECK SET THE T.V. CABLE TO SPECIFICATION; AND WITH THE BRAKES APPLIED, TAKE THE LINE PRESSURE READINGS IN THE RANGES AND AT THE ENGINE R.P.M.'S INDICATED IN THE CHART BELOW. FULL T.V. LINE PRESSURE CHECK FULL T.V. LINE PRESSURE READINGS ARE OBTAINED BY TYING OR HOLDING THE T.V. CABLE TO THE FULL EXTENT OF ITS TRAVEL; AND WITH THE BRAKES APPLIED, TAKE THE LINE PRESSURE READINGS IN THE RANGES AND AT THE ENGINE R.P.M.'S INDICATED IN THE CHART BELOW. *NOTICE TOTAL RUNNING TIME FOR THIS COMBINATION NOT TO EXCEED 2 MINUTES. CAUTION BRAKES MUST BE APPLIED AT ALL TIMES. 1981 200-4R AUTOMATIC TRANSMISSION OIL PRESSURE MODEL RANGE KPA P.S.I. KPA P.S.I. BM,BY,EG,OG,CU,PH PARK AND NEUTRAL AT 1000 RPM 385-440 385-440 55-65 55-65 830-990 945-1125 120-145 140-165 BM,BY,EG,OG,CU,PH *REVERSE AT 1000 RPM 675-775 675-775 100-110 100-110 1460-1730 1655-1970 210-250* 240-285* BM,BY,EG,OG,CU,PH *DRIVE AND MANUAL THIRD AT 1000 RPM 385-440 385-440 55-65 55-65 830-990 945-1125 120-145* 140-165* BM,BY,EG,OG,CU,PH *MANUAL SECOND AND LO AT 1000 RPM 900-1035 900-1035 130-150 130-150 900-1030 900-1030 130-150* 130-150* LINE PRESSURE IS BASICALLY CONTROLLED BY PUMP OUTPUT AND THE PRESSURE REGULATOR VALVE. IN ADDITION, LINE PRESSURE IS BOOSTED IN REVERSE, MANUAL SECOND AND MANUAL LO BY THE REVERSE BOOST VALVE. ALSO, IN THE NEUTRAL, DRIVE AND REVERSE POSITIONS OF THE SELECTOR LEVER, THE LINE PRESSURE SHOULD INCREASE WITH THROTTLE OPENING BECAUSE OF THE T.V. SYSTEM. THE T.V. SYSTEM IS CONTROLLED BY THE T.V. CABLE, THE THROTTLE LEVER AND BRACKET ASSEMBLY AND THE T.V. LINK, AS WELL AS THE CONTROL VALVE ASSEMBLY.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.