TCDS TC 221

FRANKLIN ENGINE COMPANY MODELS: Aircooled Motors Franklin 4AC-176 Series T.C. NUMBER: T.C. 221 Model- Franklin 4AC-176 B2, B3 BA2 (O-175- 1), BA3 C2, C3 D2, D3 F2, F3 Type 4HOA - - - - - - - - - - - - - - - - Rating: Maximum continuous, hp, rpm, at S.L. press. alt. 65-2200-S.L. 65-2300-S.L. 75-2500-S.L. 80-2650-S.L. 80-2500-S.L. Take-off, hp, rpm, full throttle 65-2200 65-2300 75-2500 80-2650 80-2500-S.L. Fuel (minimum octane aviation gasoline) 73 - - - - 80 - - - - - - - - Bore and stroke, in. 4.0 x 3.5 - - - - - - - - - - - - - - - - Displacement, cu. in. 176 - - - - - - - - - - - - - - - - Compression ratio 6.3: 1 6: 1 6.3: 1 - - - - 7: 1 Weight (dry), lbs. 182; 189 - - - - - - - - - - - - 183; 190 C.G. location (with all accessories) Forward of rear mount C.L., in. 5.7; 3.7 - - - - - - - - - - - - - - - - Propeller shaft Special with integral flanged hub, 6-3/8 in. bolts - 4 in. circle - - - - - - - - - - - - - - - - Carburetion Marvel MA-3 or MA-3A carburetor with 1-9/64 in. venturi Marvel MA-3P or MA-3SPA carburetor with 1-5/16 in. venturi Marvel MA-3 or MA-3A carburetor with 1-5/16 in. venturi - - - - - - - - Ignition, dual Eisemann AM- 4 (unshielded) or LA-4 (shielded) magnetos with impulse coupling (retard 25 degrees) - - - - - - - - - - - - - - - - Ignition timing, deg. BTC 26 or 28 - - - - - - - - - - - - - - - - Spark plugs Champion C- 10S, AJ-66, 78S; Simmonds- Benton 4D3- S; AC SA- - - - - - - - - - - - - - - - - 47; Auto-Lite A5-B or A4- S Oil sump capacity, quarts 4 or 5 - - - - - - - - - - - - - - - - Certification basis Type Certificate No. 221 (See NOTE 2) NOTE 1. Maximum permissible cylinder head, cylinder barrel and oil inlet temperatures, 500 degrees F., 335 degrees F., and 240 degrees F., respectively. NOTE 2. Approval expired 11/5/50. No engines of these models manufactured after the date shown below or with serial numbers above those noted are eligible for use in certificated aircraft. Date Model Serial No. Date Model Serial No. 4/1/42 4AC-176B2 101706 7/10/45 4AC-176BA3, C2, C3 102172 4/1/42 4AC-176B3 100306 7/10/45 4AC-176D2 125356 9/29/50 4AC-176BA2 102234 9/4/41 4AC-176D3 125356 5/15/41 4AC-176F2 125128 5/18/41 4AC-176F3 125351 NOTE 3. The following accessories are eligible for use on the specified engine models at the indicated additional weights: Accessory Weight (lbs.) Optional Accessories Housing for F2 only With drives for two generators, starter, hydraulic and vacuum pump 12 Generator Auto-Lite GDY or GAS (6 or 12 volts, Models B3, C3, D3, F3, BA3 only) 12 Auto-Lite No. 10621 and 10622 (both used, F2 only) 26 Starter Auto-Lite MBG or MZ (6 or 12 volts, Models F2, B3, BA3, C3, D3, F3 only) 16 Fuel Pump AC No. 10551 3 Hydraulic Pump Pesco 194-C (F2 only) 3 Vacuum Pump Pesco 194-C (F2 only) 4 Miscellaneous Fram P-1/2 or PB-1/2 oil filter 2 8 quart finned oil sump -- AC air cleaner, No. 1529265 (65 hp models only) The following drives are provided: Accessory Nearest AN Pad Designation Direction of Rotation, C = Clockwise CC = Counter- clockwise Drive Speed I Crankshaft RPM Maximum Torque (in. - lbs.) Continuous Static Maximum Overhang Moment (in. - lbs.) Starter None CC 11.444: 1 - - 240 30 Generator None CC 1.000: 1 8 15 45 Tachometer AND 10005 CC 0.500: 1 20 60 2 NOTE 4. Military model C-175-1 is identical to Model 4AC-176BA2. The corresponding model designation and T.C. No. 221 should be incorporated on the engine nameplate when used in certificated aircraft.