Mitsubishi 4G91 engine
Content
The Mitsubishi 4G91 engine has established itself as one of the most reliable automotive components. This unit has been used in the construction of vehicles for over 20 years.
The equipment has gained fame due to its resistance to heavy loads.
Engine description
Mitsubishi 4G91 saw the light in 1991 as part of the design of the fourth generation Mitsubishi car. The engine was produced until 1995 for specific models, after which it began to be manufactured for Mitsubishi (station wagon). As part of this vehicle, production was carried out until 2012. The engine was produced at factories located on the territory:
- Japan
- The Philippines;
- USA.
Initially, the power of the equipment was 115 horsepower. The engine was used for Lancer and Mirage modifications. Later, a model of this engine was released, having a power of 97 horsepower, which included a carburetor.
Technical specifications
The basic technical characteristics of the engine are determined by its name. Each letter and number indicates certain design features of the device:
- the first digit indicates the number of cylinders;
- the next letter indicates which engine is used;
- the two digits at the end are the aggregate series.
This interpretation applies exclusively to engine models up to 1989. Thus, the Mitsubishi 4G91 engine has four cylinders and is type G. This letter is an abbreviation for the word "Gasoline", which translates as "gasoline". Series 91 indicates that the production of the device started in 1991.
The volume of the device is 1496 cubic centimeters. Power varies from 79 to 115 horsepower. A feature of the four-cylinder engine is the presence of a DOHC - gas distribution device (based on a toothed belt). This system involves equipping each cylinder with four valves.
Each cylinder block has a drive connected to a camshaft. The diameter of one cylinder is from 71 to 78 millimeters. The cylinder head is made of aluminium. In total, the scheme has 16 valves. 8 valves are responsible for intake, and 8 for exhaust. Cooling is done by liquid method.
The engine has an ordinary shape and a transverse arrangement. The device works on 92 and 95 grades of gasoline. The combustible mixture is supplied by injection through the injector into the intake manifold. Fuel consumption depends on the type of driving, and can range from 3,9 to 5,1 liters per 100 kilometers. Depending on the modification, the vehicle can be refueled with 35-50 liters of fuel.
The highest torque indicator reaches 135 H * m at 5000 rpm. The compression ratio is 10. The piston stroke is from 78 to 82 millimeters. The design assumes the presence of 5 crankshaft bearings. The suction device acts as a turbine.
Motor reliability
The 4G91 engine features low fuel consumption compared to analogues, and quick response, has a wear-resistant starter, and a distributor that can withstand heavy loads. This model is able to withstand 400 thousand kilometers, but this figure depends on the specific device. The engine is designed for the European market, and is adapted for use in difficult conditions.
In terms of reliability, the 4G91 internal combustion engine is one of the Mitsubishi engines with the lowest breakdown rate. The most common failure of this device is the chirping of hydraulic valve lifters. Due to the automatic transmission, the engine is difficult to accelerate to maximum power. For fans of a quiet ride, this drawback does not play a significant role.
Reviews say that one drawback of the 4G91 engine is its use on right-hand drive Lancer models. This feature does not affect the reliability of the engine, but creates additional inconvenience for the driver.
In addition, in Russia and other CIS countries there are restrictions on the use of right-hand drive vehicles. Despite this, the engine is popular because it has a high reliability index.
Maintainability
The 4G91 engine rarely fails, which is both a plus and a minus. The advantage lies in the long operating period of the equipment. The disadvantage is associated with a small amount of information, which is why self-repair and timing replacement are quite difficult. At the same time, the engine has a high maintainability ratio.
If necessary, individual interchangeable components can be replaced in the 4G91 model, or mechanical manipulations can be carried out in violation of the integrity of the structure, but without causing harm and reducing productivity.
Repairs, adjustments and maintenance are recommended to be carried out at service centers. New models of this engine cost from 35 thousand rubles.
The advantage of the 4G91 engine is that, if necessary, it can be converted into a 4G92 modification. The result is a slightly modified design and layout of the carburetor. In this case, the power of the device will increase significantly.
List of cars on which this engine is installed
The 4G91 engine is used on fourth generation Mitsubishi models. The device can be installed on Lancer sedans manufactured during:
- from 1991 to 1993;
- from 1994 to 1995 (restyling).
The unit also works on Mirage models, let in:
- from 1991 to 1993 (sedan);
- from 1991 to 1995 (hatchback);
- from 1993 to 1995 (coupe);
- from 1994 to 1995 (sedan).
Engine runs on: Mitsubishi Colt, Dodge/Plymouth Colt, Eagle Summit, Proton Satria/Putra/Wira, Mitsubishi Libero (Japanese only). On other models not listed, the 4G91 engine cannot be used. Installation and configuration is possible only in theory, and can lead to negative consequences.
