OLDSMOBILE RECOMMENDS THE USE OF NO. 1-D OR WINTERIZED NO. 2-D DIESEL FUELS FOR TEMPERATURES BELOW 20F. THIS IS REQUIRED BECAUSE PARAFFIN WAX FLAKES FORM IN DIESEL FUEL AT LOW AMBIENT TEMPERATURES. NO. 2-D DIESEL FUEL CONTAINS MORE PARAFFIN AND, THEREFORE, MORE FLAKES MAY BE PRODUCED, TO THE POINT WHERE THE FUEL FLOW THROUGH THE FILTERS MAY BE RESTRICTED. OLDSMOBILE IS NOW MAKING AVAILABLE AN OPTIONAL FUEL LINE HEATER ON CURRENT PRODUCTION BUILT CARS. THIS SYSTEM CONSISTS OF A FILTER IN THE FUEL TANK WITH A CHECK VALVE AND A FUEL LINE HEATER IN THE LINE PRIOR TO THE FINAL FILTER. IF THE TANK FILTER PLUGS, THE CHECK VALVE WILL OPEN, ALLOWING FUEL CONTAINING WAX FLAKES TO BE PUMPED TO THE HEATER. THE HEATER RAISES THE FUEL TEMPERATURE AND MELTS THE WAX, PREVENTING RESTRICTION OF THE FINAL FILTER. OLDSMOBILE IS ALSO NOW MAKING AVAILABLE AT OWNER'S EXPENSE A DIESEL FUEL LINE HEATER SYSTEM KIT. OWNERS MAY WISH TO CONSIDER DEALER INSTALLATION OF THIS SYSTEM BASED UPON FUEL AVAILABILITY OR TEMPERATURE CONDITIONS IN THEIR LOCAL AREAS. INSTALLATION DETAILS AND PARTS REQUIREMENTS ARE ATTACHED TO THE APRIL ISSUE OF THE OLDSMOBILE SERVICE GUILD. NOTE: OWNERS WHO ELECT TO HAVE THE FUEL LINE HEATER SYSTEM INSTALLED SHOULD BE ADVISED TO KEEP THE FUEL TANK MORE THAN ONE-QUARTER FULL WHEN THE TEMPERATURE IS BELOW 20F TO HELP PREVENT THE POSSIBILITY OF RUNNING OUT OF FUEL. ADDITIONAL INFORMATION ON THIS RECOMMENDATION MAY BE FOUND IN THE INSTALLATION PROCEDURE. DIESEL FUEL LINE HEATER SYSTEM 1978-1981 INSTALLATION PROCEDURES AND PARTS INFORMATION FUEL LINE HEATER INSTALLATION PROCEDURE 1.DISCONNECT THE NEGATIVE CABLES FROM BOTH BATTERIES. 2.REMOVE THE AIR CLEANER AND INSTALL THE PROTECTIVE COVER ON THE EXHAUST CROSSOVER. 3.REMOVE REAR COMPRESSOR BRACE TO INTAKE MANIFOLD AN A/C CARS OR THE UPPER ALTERNATOR BRACKET ON NON A/C CARS. 4.DISCONNECT THE TV CABLE AT THE BELLCRANK AND DISCONNECT THE TV CABLE BRACKET. MOVE IT OVER THE TOP OF THE FUEL PIPE. 5.DISCONNECT AND MOVE OUT OF THE WAY ALL VACUUM HOSES AND ELECTRICAL WIRES THAT ARE ROUTED OVER THE TOP OF THE FUEL PIPE. 6.ON 1981 MODELS REMOVE THE CRANKCASE VENTILATION PIPE FROM THE REAR OF THE INTAKE MANIFOLD. 7.ON 1980-81 MODELS DISCONNECT THE FUEL RETURN LINE PIPE FROM THE INJECTION PUMP AND MOVE TO THE SIDE. 8.REMOVE THE FUEL PIPE THAT RUNS BETWEEN THE PUMP AND FILTER. (ON SOME MODELS IT MAY HELP TO CUT THE PIPE TO REMOVE IT). 9.INSTALL A STUD BOLT IN THE RIGHT HAND SIDE OF THE WATER OUTLET. MOST 1981'S WILL HAVE THE STUD BOLT INSTALLED. 10.ON 1978-79-80 MODELS BEND THE TAB HOLDING THE ELECTRICAL SHEATH ON THE RIGHT HAND VALVE COVER UP TO A 45FANGLE (FIG.3). 11.INSTALL THE HEATER AND PIPE ASSEMBLY AND BOTH CLIPS (FIG. 4). IT MAY BE NECESSARY TO LOOSEN THE WING NUT ON THE FILTER TO START THE THREADS. NOTICE: ON 1980 MODELS IF THERE IS NOT AT LEAST A 1/32 INCH CLEARANCE BETWEEN THE FUEL LINE AND THE INJECTION LINE BRACKET, PERFORM THE FOLLOWING UNTIL THE CLEARANCE IS OBTAINED. DO NOT BEND THE FUEL LINE- DAMAGE TO THE HEATER MAY OCCUR. IF CLEARANCE IS NOT AT LEAST 1/32 INCH, LOOSEN THE RIGHT HAND SIDE OF THE FUEL FILTER BRACKET. PUT A 1/8 INCH FRONT END SHIM UNDER THE BRACKET TO RAISE IT UP. BEND THE BRACKET DOWN AS SHOWN IN FIG. 5. PRY THE FUEL HEATER UP BY INSERTING A SCREW DRIVER UNDER THE HEATER CLAMP AND PRYING UPWARDS. 12.RECONNECT THE FUEL RETURN LINE TO THE 1980-81 INJECTION PUMP. 13.USE A TIE STRAP AND TIE THE ELECTRICAL WIRE SHEATH TO THE INJECTION LINES ON THE RIGHT HAND VALVE COVER. 14.ON 1978-79-80 CARS CONNECT THE FEMALE ELECTRICAL CONNECTOR FROM THE FUEL HEATER TO THE INJECTION PUMP FUEL SOLENOID. CONNECT THE FUEL SOLENOID CONNECTOR TO THE PIGTAIL ON THE FUEL LINE HEATER (FIG. 6). ON 1981 MODELS, DISCONNECT THE CONNECTOR IN THE EGR SWITCH LEAD, CONNECT THE FUEL LINE HEATER INTO THIS CIRCUIT AS SHOWN IN FIG. 7. 15.RECONNECT ALL VACUUM LINES AND ELECTRICAL WIRES. 16.RECONNECT THE T.V. CABLE BRACKET AND HOOK THE T.V. CABLE TO THE BELLCRANK. 17.REINSTALL THE REAR COMPRESSOR BRACE ON THE ALTERNATOR BRACKET. 18.RECONNECT THE NEGATIVE BATTERY CABLES, START THE ENGINE AND CHECK FOR LEAKS. 19.REINSTALL THE AIR CLEANER. FUEL TANK PARTS PROCEDURE 1.REMOVE FUEL TANK, REFER TO APPLICABLE SERVICE MANUAL. 2.REMOVE THE FUEL TANK SENDER. 3.ON THOSE MODELS REQUIRING THE COMPLETE FUEL SENDER, PROCEED TO STEP 8. 4.SECURE THE TANK SENDER IN A VISE JUST BELOW WHERE THE FLOAT ASSEMBLY IS WELDED TO THE PICKUP TUBE. NOTICE: CARE MUST BE TAKEN TO AVOID CRUSHING OR DISTORTING ANY PART OF THE TANK SENDER. 5.PLACE A 7/16 INCH OPEN END WRENCH AROUND THE METAL SLEEVE OF THE FILTER. REMOVE THE FILTER BY TAPPING WITH A SMALL MALLET AGAINST THE WRENCH. REMOVE TANK SENDER FROM THE VISE. 6.REMOVE TEMPLATE FROM BULLETIN AND PLACE ON TABLE TOP AS SHOWN IN FIG. 8. ALIGN MOUNTING FLANGE OF SENDER AS SHOWN ON TEMPLATE. MOVE THE FUEL SENDER UNTIL THE FUEL INLET IS OVER THE CORRECT LINE. THEN POSITION THE FILTER AT THE CORRECT ANGLE AND TAP ON THE PIPE TO INSTALL FILTER. NOTICE: FILTER SHOULD NOT CONTACT SHARP EDGES WHEN BEING INSTALLED TO PREVENT DAMAGE. 7.REINSTALL THE TANK SENDER. 8.REINSTALL FUEL TANK, REFER TO APPLICABLE SERVICE MANUAL.
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.