TELEDYNE CONTINENTAL AIRCRAFT ENGINE SERVICE INFORMATION LETTER Contains Useful Information Pertaining to Your Aircraft Engine Category 5 SIL 04-1 Technical Portions are FAA Approved SUBJECT: PURPOSE: Installation of the Altitude-Compensating Fuel Pump on IO-240-B Series Engines. To provide instructions for the installation of the altitude compensating fuel pump on IO-240-B series engines. COMPLIANCE: Optional MODELS AFFECTED: All IO-240-B series engines GENERAL Teledyne Continental Motors has approved the altitude compensating fuel pump for installation on the IO-240 series engines. This installation is at the owner/operators discretion and is not mandatory, however it is recommended for aircraft used at high density altitude airports. The following installation and fuel system set-up procedures must be followed when installing the altitude compensating fuel pump. INSTALLATION INSTRUCTIONS 1) Referring to the airframe manufacturers maintenance instructions: (a) Remove the upper and nose engine cowlings from the aircraft. WARNING Magnetos must be verified to be grounded and fuel to be selected to the off position when moving the propeller by hand, or personal injury may result. (b) Remove electrical power from the aircraft. (c) Shut off the fuel supply to the engine by closing the fuel shutoff valve. (d) Remove the forward baffle assembly. If a belt driven standby alternator is installed, removal of the alternator will be required to facilitate removal of the baffle assembly. CAUTION Attempting to remove the forward baffle assembly without removing the standby alternator, or attempting to replace the fuel pump assembly without completely removing the forward baffle assembly, may result in damage to the forward baffle assembly. 1 of 5 2003 TELEDYNE TECHNOLOGIES, INC.
INSTALLATION INSTRUCTIONS con t 2) Remove the standard fuel pump assembly using the instructions contained in the IO-240 Overhaul Manual Form X30622A Section 9. Remove and retain the fuel pump drive shaft for installation, if serviceable. 3) Install the altitude compensating pump assembly P/N 649368-49A1 in accordance with the instructions contained in the IO-240 Overhaul Manual Form X30622A section 19-5. 4) Contact the airframe manufacturer for rework or replacement instructions for the front baffle assembly. After replacement or rework, reinstall the baffle assembly (and standby alternator, if installed) using the airframe manufacturers maintenance instructions. 5) Contact the airframe manufacturer for replacement mixture control cable or the appropriate mixture control cable rework instructions. After rework or replacement, connect and rig the mixture control cable in accordance with the airframe manufacturer s maintenance instructions. 6) Open the fuel shutoff valve and static leak check the fuel pump assembly. Correct any defects noted before proceeding to the next step. 7) Restore electrical power to the aircraft. Using the fuel boost pump, leak check the fuel system. Correct any defects noted before proceeding to the next step. WARNING Over priming can cause a flooded intake resulting in a hydraulic lock condition and subsequent engine damage or failure. If the engine is over primed, or flooded, make sure that all fuel has drained from the intake and cylinders prior to attempting engine start. 8) Perform the fuel system setup in accordance with the procedures contained in TCM bulletin SID97-3B. NOTE Pressure altitude must be used for the figures below when determining fuel system set-up values. To determine pressure altitude prior to take-off, set your altimeter to 29.92 in hg, and the altimeter will indicate your pressure altitude. 2 of 5
Idle Set unmetered pump pressure at 1000 +/- 25 rpm to 9.6 +/- 0.2 psi (Sea Level, Standard Day). For other pressure altitudes, determine required unmetered pressure setting from the plot below. NOTE: Pressure altitude must be used for the figures below when determining fuel system set-up values. To determine pressure altitude prior to take-off, set your altimeter to 29.92 in hg, and the altimeter will indicate your pressure altitude. IO240B Idle Unmetered Pressure Altitude Plot @ 1000 RPM Unmetered Pressure (psi) 10 9.8 9.6 9.4 9.2 9 8.8 8.6 8.4 8.2 8 7.8 7.6 7.4 7.2 7 6.8 6.6 6.4 6.2 6 5.8 5.6 5.4 5.2 5-500 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 10000 Figure 1 Unmetered fuel pressure adjustment Adjust idle mixture screw to set RPM rise during mixture check at 1000 RPM to 20 to 50 RPM rise. 3 of 5
Full Throttle Ground Check Adjust the aneroid rod to obtain the metered nozzle pressure at pressure altitude and rpm per the chart below. Turn clockwise to decrease pressure and counter-clockwise to increase pressure. After adjustment, recheck idle unmetered pressure setting 13.0 12.5 12.0 11.5 Full throttle ground fuel pump set-up Full Rich mixture setting Metered Nozzle Pressure (psi) 11.0 10.5 10.0 9.5 9.0 8.5 8.0 7.5 7.0 2250 rpm 2300 rpm 2350 rpm 2400 rpm 2450 rpm 6.5-1000 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 NOTE: Pressure altitude must be used for the figures below when determining fuel system set-up values. To determine pressure altitude prior to take-off, set your altimeter to 29.92 in hg, and the altimeter will indicate your pressure altitude. Note: If full throttle was readjusted, idle setting must be rechecked and adjusted, if required. After all adjustments are completed, reset idle to 850 RPM +/- 25 RPM and verify mixture rise, acceleration / deceleration without excessive idle speed dip, and idle stability. FIGURE 2 Metered Fuel Pressure Verification 4 of 5
IO-240-B Engine with Aneroid Fuel Pump, Full Throttle, Full Rich Mixture @ 2450 RPM Pressure Altitude (Set Altimeter at 29.92 in. Hg) Fuel Flow (lbs/hr) Fuel Flow (gals/hr) Metered Fuel Pressure PSID (feet) Minimum Maximum Minimum Maximum Minimum Maximum Sea Level 53.5 60 9.1 10.2 11.4 13.3 1,000 50.3 55.5 8.6 9.5 10.7 12.3 2,000 47.5 52 8.1 8.9 10.2 11.4 3,000 45.1 48.7 7.7 8.3 9.7 10.7 4,000 43 46.1 7.3 7.9 9.3 10.1 5,000 41.3 44 7.0 7.5 9 9.6 6,000 39.8 42.1 6.8 7.2 8.8 9.3 8,000 37.7 39.5 6.4 6.7 8.5 8.8 10,000 36.1 37.9 6.1 6.5 8.3 8.5 12,000 35.1 36.9 6.0 6.3 8.2 8.4 14,000 34.4 36 5.9 6.1 8.1 8.3 Typical IO240B (with altitude compensating fuel pump) fuel flow leaning curve during flight test. Note: Actual RPM may vary due to constant speed prop operation at full throttle. 65 IO240B Altitude Leaning Schedule @ 2450 rpm, full rich mixture 60 55 MAX Fuel Flow (pph) 50 45 MIN 40 35 30 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000 Figure 3 Altitude Performance Verification 5 of 5