The Mitsubishizaibatsu had been broken up into three companies by the US occupying forces. Automobile and truck engines were mainly built by three branches of one of these companies, Central Heavy Industries (Shin-Mitsubishi Heavy Industries from 1952). These three branches (Mizushima, Nagoya, and Kyoto Engineering Works) were established as clusters of the many small aircraft factories built during the war.[1] Thus, Mizushima developments gained theME code, followed by a numerical, while engines developed in Nagoya became theNE-series and Kyoto-developments were namedKE. The numbers do not in any way relate to each other or across letter codes and were purely issued in order of development. In 1964 the three companies were merged intoMitsubishi Heavy Industries and eventually a new naming system emerged.
Since the introduction of the2G10 engine in October 1968, Mitsubishi engines use a four-digit naming convention:
The second (letter) formerly referred to the fuel type; "D" = diesel, "G" = gasoline. However, since the 1980s, this has changed. Two engine families were introduced using the letter "A" to denote that all the engines in the family had analloycylinder head. Their latest engines, however, do not follow any previous conventions (e.g.4M4,3B2, etc.).
The third (digit) previously denoted the engine family. Five of the "4G" straight-four engine families had distinct names; "4G1" = Orion, "4G3" = Saturn, "4G4" = Neptune, "4G5" = Astron, and "4G6" = Sirius.
The fourth (digit) is the specific engine model within the family, issued in order of development. It is not a guide to its placewithin that family, nor is it a guide to the capacity of the engine.
There may also be supplementary letters after the initial four characters. "T" can indicate that the engine is turbocharged (e.g.4G63T), "B" that this is the second version of the engine (e.g.4G63B). Where engine codes are used which include the supplemental letters, the first digit denoting the number of cylinders may be omitted, so4G63T may be seen asG63T.
These were used in Mitsubishi's very first vehicles,motor scooters and three-wheelers.
A-series — A 744 cc air-cooled OHV engine installed as the 3A in the 1947 Mitsubishi TM3A three-wheeled truck. The TM6 three-wheeler of 1955 was equipped with an improved6A engine.
1952-196? —ME10/12 — A development of the A family engine ("Mizushima Engine"). ThesidevalveME10 displaces 886 cc (TM4 and TM5 three-wheeled trucks), while the later,OHVME12 is of 851 cc.
As fitted to the 1.25-tonne (2,760 lb)Mitsubishi "Mizushima" TM14G three-wheeled truck, the ME12 developed 27 PS (20 kW) at 3600 rpm.[2]
NE/NE1 — "Nagoya Engine," First introduced as the 112 ccside-valve,air-cooled 1.5 hpNE10 for the famousSilver Pigeon scooter. Later iterations included theNE7, the enlarged 192 ccNE9, and theOHV 125 ccNE8 and 175 ccNE13.
ME20 — This 309 air-cooledOHV engine served in the three-wheeledLeo.
Mitsubishi's smallest powerplants, most commonly found in their earliest models in the 1960s:
1955-1962 —ME7/15/18 — This was Mitsubishi's first air-cooled OHV engine over one liter's displacement. In 1955, the 1276 ccME7 was developed for the 1.5-tonne (3,310 lb)Mitsubishi TM7. The 1145 ccME15 and the 1489 ccME18 were premiered in 1958 for the TM15/16 and TM17/18 trucks; production of this engine series ended when Mitsubishi discontinued heavier three-wheeled trucks.
1960-1962 —NE19A — 0.5 L — The air-cooled 493 ccOHV twin-cylinder engine in theMitsubishi 500, the first passenger car built by the company after theSecond World War. Bore and stroke were 70.0 x 64.0 mm
1961-1965 —NE35A — 0.6 L — a 594 cc iteration of the NE series, 72.0 x 73.0 mm. This engine was used in theMitsubishi 500 Super DeLuxe andMitsubishi Colt 600.
1968-1976 —2G1 — 0.36 L — First introduced in late first generationMinicas in October 1968 to gradually replace theair-cooledME24 powerplant. The water-cooled2G10 was atwo-stroke engine like its predecessor.
1972-1988 —2G2 "Vulcan" — 0.36-0.8 L — a newfour-strokeOHC design introduced in 1972 to succeed the 2G1, fitted to Minicas andMinicabs. 359 cc, 471 cc, 546 cc, 644 cc and 783 cc versions were produced. It also equipped theMazda Porter Cab.
Two 2659 ccstraight-4 normally aspirated andturbodiesels,4DR5 and4DR6, fitted to some Canter light trucks, and also fitted to the company'sJeep which it built under licence fromWillys between 1953 and 1998. Also used in some larger forklift trucks.
4DR5: Bore x stroke 92.0mm x 100.0mm. Capacity 2659cc. Compression ratio 20.0:1. Naturally aspirated power output 80PS @ 3,800rpm. Torque output 18.0 kg/m @ 2,200rpm. The indirect injected 4DR5 produced from naturally aspirated 75 to 80 PS (55 to 59 kW), while the turbocharged and intercooled versions produced a torque of 22.5 kg/m (220.65 Nm) at 2000 RPM and had a compression ratio of 21.5:1, with a maximum power of 100 PS (74 kW) at 3,300 rpm.
4DR6 with direct injection has a lower compression ratio of 17.5 producing a torque of 21.0 kgm (205.94 Nm) at 2000 rpm with a maximum power of 94 PS (69 kW) at 3,500 rpm[1]
1980–present —4D5 — 2.3-2.5 L — diesel versions of the"Astron" engine
1983-2008 —4D6 — 1.8-2.0 L — diesel versions of the"Sirius" engine
1999-2008 —8A8 — 4.5 L — For its Japan-onlyProudia andDignity models, Mitsubishi built an alloy-headed 4.5 LV8 withGDI. The vehicles proved unsuccessful, and were quickly discontinued. However, the range had been developed in conjunction with theHyundai Motor Company, whoseHyundai Equus fared much better.
^Toma, Setsuo (2019-08-27)."「モーターファン」誌1952年1月号に載った広告" [Advertising in the January 1952 issue of "Motorfan" magazine].M-Base (in Japanese). Miki Press. Archived fromthe original on 2019-12-19.
^路畑寺夜村 (1994-10-01). "三菱号三輪トラックTM14G「みずしま」が生んだ単気筒小型トラックの絶巓" [The single-cylinder small three-wheeled TM14G "Mizushima" mountain truck produced by Mitsubishi].Old-timer (in Japanese). Vol. 4, no. 5,18. YAESU Publishing co.ltd. [八重洲出版]. p. 39.
