Fuel System Servicing Aircraft Refueling Aircraft refueling may be accomplished through a filler located in the top of each wing tank (Model 28/29 &31 Series), or through the fuselage tank filler (Model 28/29) or through a filler in the top of each tip tank (Model 23, 24, 25 & 35/36 Series) or through the optional Single Point Pressure Refueling (available on Model 31 Series). Replenish Fuel Tank (Overwing Manual) A. Ground airplane and fueling truck. WARNING: AIRPLANE AND FUELING TRUCK MUST BE PR0PERLY GR0UNDED BE0RE ANY FUELING OPERATION TO PREVENT POSSIBILITY OF FIRE OR EXPL0SION DUE TO DISCHARGE OF STATIC ELECTRICITY. B. Provide electrical power if needed. C. Ground fueling nozzles to ground Jacks adjacent to fill ports (if provided). WARNING: DO NOT REMOVE FILLER CAPS BEFORE GROUND FUELING NOZZLES. FIRE OR EXPLOSION COULD RESULT FROM STATIC DISCHARGE. D. Remove filler caps and start fueling operation. F. Refill tanks to desired level. G. Remove fuel nozzle and install filler cap. H. Disconnect grounding cables. I. Remove fueling truck grounding cables. J. Remove electrical power if no longer required.

Fuel Anti-Icing Protection CAUTION: On aircraft not equipped with fuel heaters, lack of anti-icing additive may cause fuel filter icing and subsequent engine flameout. The wide range of temperatures to which jet fuels are exposed in flight result in substantial changes in the water solubility of the fuel. Some jet fuels have an anti-icing additive blended at the refinery and no additional fuel preparation is required prior to aircraft servicing. Fuel supplies not containing anti-icing additive may have an additive blended with the fuel during aircraft refueling. (Refer to FAA Approved Airplane Flight Manual.) The additive functions as a freeze-point-depressant. Its partitioning characteristics make it especially effective in nullifying the icing effects of small quantities of water in jet fuels. Fuel Microbial Growth Protection Some fuel anti-icing additives also act as a biocidal agent which retards fungal and bacterial growth in fuel systems and fuel tanks. It is recommended that such an anti-icing additive be used, in the concentration specified, at each refueling and whenever a fueled aircraft will be out of service for a week or more. If microbial growth is detected, the system should be chemically treated. Refer to the applicable service or maintenance manual. Biocide Additive Biobor JF is approved for use as a biocide additive when premixed with fuel in the fuel supply facility. Over-the-wing blending of Biobor JF and fuel is not approved. Concentrations of Biobor JF up to, but not exceeding, 270 ppm can be used. CAUTION: Drain all sumps prior to refueling. Excessive water concentrations combined with excessive Biobor JF concentrations can result in the formation of solid crystalline precipitates in the fuel system. Fuel System Drain Valves Drain valves, located at low points throughout the fuel system, are used for draining condensation or sediment. A small amount of fuel should be drained from each valve after servicing and prior to the first flight of the day. The valves are spring-loaded to the closed position.

OIL SYSTEM SERVICING

Service the engine lubrication system only with the oils listed in the APPROVED OILS list. (Refer to the FAA Approved Airplane Flight Manual) Do not mix oils. The oils should be filtered through a 10-micron filter prior to use. NOTE: Check the oil level immediately after engine shutdown. While the engine is not running, oil seeps from the tank into the gearbox. A false indication of low oil supply may be obtained if the level is checked after the engine has remained shut down for a length of time. Approved Oils (Model 23, 24, 25 & 28/29 Series) Type 1 or Type 2 oils are approved. (Refer to the FAA Approved Airplane Flight Manual for a list of approved oils). NOTE: It is recommended that the engine lubrication system be serviced only with the approved Type 2 oils, since they are capable of withstanding higher operating temperatures than Type 1 oils and have improved anti-coking characteristics. Approved Oils (Model 31 & 35/36 Series) Type 2 oils conforming to Garrett Specification EMS 53110, are approved. (Refer to the FAA Approved Airplane Flight Manual for a list of approved oils). Adding Oil NOTE: Model 23, 24, 25 & 28129 series, if preflight inspection reveals that oil level in the tank is low, motor engine with starter for 30 seconds and recheck oil level. Add oil as required. If there is no oil level indication on the dipstick, add enough oil to obtain an indication, then motor with starter. Do not motor engine unless there is a positive indication of oil in the tank. Model 31 & 35/36 series, if preflight oil level checks low, start and run engine until stabilized at idle. Shut down engine and recheck oil level. If there is no oil level indication, add enough oil to obtain an indication before starting engine to recheck oil level. 1. Remove oil tank filler cap. 2. Check oil level on the dipstick and add oil (which has been passed through a 10-micron filter) to bring the oil level to the FULL mark on the dipstick. Replace and lock filler cap. NOTE: The RH engine on Model 31 and 35/36 series aircraft has a sight gage in lieu of a dipstick for checking oil level.

External Power Receptacle A standard AN power receptacle is located on the lower side of the tailcone near the tailcone access door. The receptacle provides for connecting a 28-volt DC external power unit. CAUTION: Limit external power output to a maximum of 1000 amps (1100 amps 35/36 series) when connected to this aircraft. NOTE: On aircraft with dual Battery Switches, at least one Battery Switch must be on in order to use external power.

BATTERIES Battery power is supplied by two nickel-cadmium or lead-acid batteries located in the tailcone equipment section. The batteries are of sufficient capacity to accommodate the normal electrical requirements of the airplane including starting. Normally, the batteries should not be removed in transient maintenance; however, if this should be required, adhere to the following: WARNING: Disconnect both battery quick-disconnects even though only one battery is being removed. If only one QD is disconnected, battery voltage will feed back from the connected battery and arcing will occur if the disconnected QD is inadvertently shorted to the aircraft structure. CAUTION: Do not allow any item used on or with lead-acid batteries to come into contact with nickel-cadmium batteries. Even acid fumes can damage a nickel-cadmium battery.

Battery Charging With Batteries Installed LEARJET Inc. does not recommend that batteries be charged while in the aircraft. However, if charging batteries in the aircraft becomes absolutely necessary, they may be charged using external power as follows: 1. Plug in and turn on power source. 2. Regulate output from power source to 28 volts and 1000 amps. 3. On aircraft with only one battery switch, assure switch is OFF. On aircraft with two battery switches, assure both switches are ON. 4. If batteries were discharged, do not attempt engine start until batteries have charged at least 15 minutes.

SERVICING TIRES The aircraft tires on both dual main gear and the nose gear are tubeless. They should be serviced with dry air or nitrogen to the following pressures. NOTE: +5 PSI Allowable Tolerance All Pressures. Add 4% for Loaded Tire Pressures 23,24

25

35/35A 36/36A

115

24B/D/E/F 31/31A 25B/C/D/F & 28/29 115 1400

MAIN - PSI

1150

NOSE - PSI

0

0

105

105

MODEL

105

8-Ply Rated Main Tire - 105 Standard Tire - 65; Chined Tire - 105 Standard Tire - 65; Chined Tire - 115 Aircraft Certified for 15,500 Lb TOGW –135 Aircraft Certified for: 17,000 Lb TOGW - 145 18,000 Lb TOGW - 156 18,300 Lb TOGW - 160

SERVICING OXYGEN SYSTEM The oxygen bottle is located in either of two locations: the RH nose compartment or the empennage dorsal fin. Access to the filler valve is gained either through a filler door on the RH side of the nose compartment or through a filler door on the RH side of the dorsal fin. To service the bottle, use only dry breathing oxygen, Federal Specification MIL-O-27210, Type 1, from a green-colored cylinder. Filling instructions are as follows: WARNING: Standard maintenance practices utilized for any aviation oxygen system should be followed. Precautions against oil, grease, and organic matter should be observed. 1. Close oxygen cylinder manual shutoff valve. 2. Connect recharging cylinder to aircraft filler port. 3. Open oxygen cylinder manual shutoff valve. WARNING: Slowly charge cylinder to 1750 to 1850 psig. Rapid charging will create a dangerous overheat condition. 4. Close oxygen cylinder manual shutoff valve. 5. Disconnect recharging cylinder from aircraft filler port. 6. Install filler cap on filler port and tighten. 7. Open oxygen cylinder manual shutoff valve assembly. WARNING: The oxygen cylinder manual shutoff valve must be open at all times except when servicing. Oxygen will not be available to passengers or crew if valve is left closed.