Potez 4D
A Potez 4D on display at the Wings Over the Rockies Air and Space Museum
Type	4-cyl. inverted air-cooled piston engine
National origin	France
Manufacturer	Société des Avions et Moteurs Henry Potez
Major applications	Nord 3202

The Potez 4D was a four-cylinder, inverted inline aircraft engine. It was first built shortly before World War II, but did not enter full production until 1949. Like the other D-series engines, the cylinders had a bore of 125 mm (4.9 in) and a stroke of 120 mm (4.7 in). Power for different models was in the 100 kW-190 kW (140 hp-260 hp) range.

Variants

4D-00

127 kW (170 hp)

4D-01

119 kW (160 hp)

4D-30

179 kW (240 hp)

4D-31

164 kW (220 hp)

4D-32

179 kW (240 hp)

4D-33

119 kW (160 hp)

4D-34

194 kW (260 hp)

4D-36

194 kW (260 hp) 4D-34 with aerobatic oil system

Applications

• Morane-Saulnier MS.570
• Morane-Saulnier MS.700 Petrel
• Max Holste MH.52
• Nord 1202 Norécrin
• Nord 3202
• Nord 3400
• SIPA S.70
• S.N.C.A.C. NC-840 Chardonneret

Specifications (Potez 4-D 01)

Data from Jane's All The World's Aircraft 1953-54.^[1]

General characteristics

• Type: Four-cylinder air-cooled inverted inline engine
• Bore: 125 mm (4.92 in)
• Stroke: 120 mm (4.72 in)
• Displacement: 5.85 L (352 in³)
• Length: 1,207.5 mm (47.5 in)
• Width: 510 mm (20.1 in)
• Height: 668.5 mm (26.3 in)
• Dry weight: 143 kg (314.6 lb)

Components

• Valvetrain: Two valves per cylinder with sodium cooled exhaust valves
• Fuel system: One Zenith carburettor
• Fuel type: 80 octane minimum
• Oil system: Dry sump with one pressure and two scavenge pumps
• Cooling system: air-cooled

Performance

• Power output: 119 kW (160 hp) at 2,520 rpm (take-off), 97 kW (130 hp) at 2,360 rpm (Max cruise)
• Compression ratio: 7:1
• Specific fuel consumption: 245 gram/hp/hour (take-off)
• Power-to-weight ratio: 0.83 kW/kg (0.51 hp/lb) (take-off)