International Harvester IDI
Encyclopedia
The International Harvester IDI (from Indirect Injection) engine is a 4-stroke 8-cylinder Diesel engine used in International Harvester
trucks and Ford F-Series
pickups from 1982 to 1994. The engine had two displacements: 420 cubic inches (6.9 litres), which was used in Ford trucks from 1983 until 1987, and 444 cubic inches (7.3 litres), which was used in Ford trucks from 1987 until 1993 (naturally aspirated
) and in 1993 and 1994 (turbocharged
). These engines were replaced in 1995 by the Navistar T444E (7.3L) engine, which was also marketed under the Ford Power Stroke
name.
Inc. purchased in the "Harvester" division of International Harvester which was moved within their Case
heavy equipment line. The remainder of what was International Harvester was renamed Navistar, which concentrated on engine and medium/heavy truck development. Consequently, these are actually International-Navistar IDI engines.
The engine is very loosely based on the MV446 gasoline engine, in a similar fashion to the Oldsmobile 350 c.i. V8 diesel being based on the Oldsmobile 350 c.i. gasoline engine. In both cases, while based on their gasoline cousins, the components were designed with the stresses of a diesel in mind. Unlike the failed GM diesels, these engines were completely reworked, with piston oil injection, a hardened nodular iron crankshaft, four bolt main crank caps, and roller lifters.
Finally, in 1993 Ford made available a turbocharged edition of the 7.3. The turbocharging system was produced by ATS
, which produced three turbocharging systems for the International-Navistar IDI engine; The ATS 085 and 088 turbo kits, both of which are wastegate-less designs, and the ATS 093, which included a wastegate. The Ford factory turbo system utilized the 093 and was detuned from the ATS kit. ATS formerly sold a turbine housing upgrade kit but this appears to have been discontinued. This detuning job is believed to have been due to Ford's impending use of the T444E (Power Stroke) engine. A 7.3 liter IDI in good tune with an ATS 088 turbo kit makes approximately the same power as the T444E, though it makes it at higher RPMs due primarily to turbocharger design. Factory turbo vehicles received numerous additional improvements. Pistons had an enlarged ring, added intermediate rings, an enlarged ring land and wrist pin, as well as an anodized piston face; other improvements included tweaks to the injection pump and injectors, and an upgraded oil-coolant heat exchanger.
which made it quieter than its predecessor. The indirect injection fuel system makes this popular among drivers who choose to run vegetable oil rather than petroleum fuel (the dual fuel tanks that some Ford trucks are equipped with further makes running vegetable oil easier). Both 6.9 and 7.3 liter engines use the Stanadyne DB-2 injection pump fed by a cam-driven lift pump.
International Harvester
International Harvester Company was a United States agricultural machinery, construction equipment, vehicle, commercial truck, and household and commercial products manufacturer. In 1902, J.P...
trucks and Ford F-Series
Ford F-Series
The F-Series is a series of full-size pickup trucks from Ford Motor Company which has been sold continuously for over six decades. The most popular variant of the F-Series is the F-150...
pickups from 1982 to 1994. The engine had two displacements: 420 cubic inches (6.9 litres), which was used in Ford trucks from 1983 until 1987, and 444 cubic inches (7.3 litres), which was used in Ford trucks from 1987 until 1993 (naturally aspirated
Naturally-aspirated engine
A naturally aspirated engine is one common type of reciprocating piston internal combustion engine that depends solely on atmospheric pressure to counter the partial vacuum in the induction tract to draw in combustion air...
) and in 1993 and 1994 (turbocharged
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
). These engines were replaced in 1995 by the Navistar T444E (7.3L) engine, which was also marketed under the Ford Power Stroke
Ford Power Stroke engine
Power Stroke is the name given to the diesel engines found in Ford Super Duty trucks, Ford Excursion SUVs, Ford Econoline vans, and Ford LCF commercial vehicles. Production by Navistar International Corporation for Ford Motor Company began in mid 1994, in Indianapolis, Indiana, Huntsville,...
name.
History
In 1981 Ford signed an agreement with International Harvester to produce diesel engines for their light truck line. This led directly to the production of the 6.9 liter IDI diesel. The engine was developed as a low cost, light weight diesel that fit where a V8 gas engine would, to try to convert their gas engine customers to diesel and to sell to Ford for use in F-Series light duty trucks and E-Series/Econoline vans. Before it could be sold to Ford however, TennecoTenneco
Tenneco is a $6.2 billion Fortune 500 company that has been publicly traded on the NYSE since November 5, 1999 under the symbol TEN...
Inc. purchased in the "Harvester" division of International Harvester which was moved within their Case
Case
-Academia and education:* Campaign for Science and Engineering , a non-profit organization which promotes science and engineering research in the UK* Case analysis, division of a problem into separate cases...
heavy equipment line. The remainder of what was International Harvester was renamed Navistar, which concentrated on engine and medium/heavy truck development. Consequently, these are actually International-Navistar IDI engines.
The engine is very loosely based on the MV446 gasoline engine, in a similar fashion to the Oldsmobile 350 c.i. V8 diesel being based on the Oldsmobile 350 c.i. gasoline engine. In both cases, while based on their gasoline cousins, the components were designed with the stresses of a diesel in mind. Unlike the failed GM diesels, these engines were completely reworked, with piston oil injection, a hardened nodular iron crankshaft, four bolt main crank caps, and roller lifters.
7.3
In 1987, the 6.9 liter engine was supplanted by the 7.3 liter upgrade, with over 300,000 6.9s shipped to Ford and countless numbers installed into medium-duty trucks, school buses, and the like. This engine features numerous improvements over the 6.9 liter, with most of the changes located in the heads; the block received an increase bore and select-fit pistons, while the heads received an enlarged prechamber, enlarged valve stem shields, harder valves, and other minor upgrades. The front cover was revised to reduce seepage.Finally, in 1993 Ford made available a turbocharged edition of the 7.3. The turbocharging system was produced by ATS
ATS
-Societies:*Adventist Theological Society*American Temperance Society, an early American civic organization promoting temperance*American Thoracic Society, a society for lung physicians, health related professionals and researchers-Systems:...
, which produced three turbocharging systems for the International-Navistar IDI engine; The ATS 085 and 088 turbo kits, both of which are wastegate-less designs, and the ATS 093, which included a wastegate. The Ford factory turbo system utilized the 093 and was detuned from the ATS kit. ATS formerly sold a turbine housing upgrade kit but this appears to have been discontinued. This detuning job is believed to have been due to Ford's impending use of the T444E (Power Stroke) engine. A 7.3 liter IDI in good tune with an ATS 088 turbo kit makes approximately the same power as the T444E, though it makes it at higher RPMs due primarily to turbocharger design. Factory turbo vehicles received numerous additional improvements. Pistons had an enlarged ring, added intermediate rings, an enlarged ring land and wrist pin, as well as an anodized piston face; other improvements included tweaks to the injection pump and injectors, and an upgraded oil-coolant heat exchanger.
Fuel system
These engines are unusual today in that the fuel system is entirely mechanical, though this was the standard for diesels of the day and indeed for the earliest fuel-injected gasoline vehicles. The fuel system also utilizes indirect injectionIndirect injection
In an internal combustion engine, the term indirect injection refers to a fuel injection where fuel is not directly injected into the combustion chamber...
which made it quieter than its predecessor. The indirect injection fuel system makes this popular among drivers who choose to run vegetable oil rather than petroleum fuel (the dual fuel tanks that some Ford trucks are equipped with further makes running vegetable oil easier). Both 6.9 and 7.3 liter engines use the Stanadyne DB-2 injection pump fed by a cam-driven lift pump.