Ford Power Stroke engine

Ford Power Stroke engine
Overview
Manufacturer	Ford Motor Company (2010-Present)
Also called	Ford diesel
Production	1994-present
Layout
Configuration	OHV 90° V8 Diesel
Chronology
Predecessor	International Engine Corporation 1994-2010

PowerStroke 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. These engines were produced by Navistar for Ford until 2010, when Ford released a newly designed 6.7 Liter Powerstroke engine (codenamed the Scorpion and built in house by Ford in their Chihuahua, Mexico facility along with a newly redesigned interior and exterior. These engines primarily compete in the United States full-size pickup truck market with the Duramax V8 from General Motors/Isuzu DMAX and the B series straight 6 from Cummins.

7.3 Power Stroke

Main article: Navistar T444E engine

7.3 Power Stroke
Overview
Manufacturer	Navistar International
Production	1994.5-2003.5
Layout
Configuration	V8
Displacement	7.3 L, 444 cu³
Cylinder bore	4.11 inches
Piston stroke	4.18 inches
Cylinder block material	Iron
Cylinder head material	Iron
Valvetrain	OHV
Combustion
Fuel type	Diesel
Output
Power output	185-225 hp
Torque output	350-375 lb-ft
Dimensions
Dry weight	≈920 lbs (Dry)
Chronology
Predecessor	7.3 L IDI Ck
Successor	6.0 Power Stroke

In mid 1994, the 7.3L Power Stroke diesel was introduced. Although the previous 7.3L had the same displacement, there weren't any other similarities between the two.

The Power Stroke is an electronically controlled, direct injection engine with a 4.11 in (104 mm) bore and 4.18 in (106 mm) stroke creating a displacement of 444 cu in (7.3 L). It has a 17.5:1 compression ratio, and has a dry weight of approximately 920 lb (420 kg). This engine produced up to 250 hp (190 kW) and 505 lb⋅ft (685 N⋅m) of torque in automatic trucks during the last years of production, and 275 hp (205 kW) and 520 lb⋅ft (705 N⋅m) of torque in manual trucks.

The 1994.5 to 1996/97 DI Power stroke had "single shot" HEUI (hydraulically actuated electronic unit injection) fuel injectors and ran a high pressure oil pump (HPOP) to create the necessary oil pressure to fire the fuel injectors, with a 15° timing value. 1994.5-1997 trucks used a cam driven fuel pump, whereas the 1999-2003 trucks used a frame rail mounted electric fuel pump. The California trucks in 1996 and 1997 had split shot fuel injectors whereas the rest of the trucks didn't get split shots until 1999. The difference between the split shot and single shot are the single shot only injects one charge of fuel per cycle, whereas the split shot releases a preliminary light load before the main charge to initiate combustion in a more damped manner. This controlled injection helps reduce the sharp combustion 'knock'.

It utilizes a single turbocharger with a turbine housing size of 1.15 A/R. In 1999, an air to air intercooler was added to cool the charged air from the turbo making it more dense. The cooler, denser air would increase the horsepower potential of the engine, while also reducing exhaust gas temperatures (EGTs). Eventually, the turbine housing was changed to a .84 A/R housing and a wastegate was added. With larger injectors, the HPOP was advanced to 17° to change fueling characteristics.

The 7.3 L DI Power Stroke was in production until the middle of model year 2003 when it was replaced by the 6.0L because of its inability to meet newer emission requirements. Due to its popularity,nearly 2 million 7.3s were produced from International's Indianapolis plant.

6.0 Power Stroke

Main article: 6.0L Power Stroke

The 7.3 L (444 CID) Power Stroke was replaced by the 6.0 L (365 CID) midway through the 2003 model year. The 6.0L Power Stroke was used in Ford Super Duty trucks until the 2008 model year but lasted until 2009 in Ford Econoline vans (Model year 2010). The engine has a 3.74 in (95 mm) bore and 4.13 in (105 mm) stroke creating a displacement of 365 cu in (6.0 L) or 5954 cc. It utilizes a variable geometry turbocharger and intercooler, producing 325 hp (242 kW) and 570 lb⋅ft (773 N⋅m) with an 18:1 compression ratio, with fuel cutoff at 4200 rpm, but having a redline of 4500 rpm only attainable with aftermarket performance programming.

Some of the 6.0 L PowerStroke engines have proven to be problematic, and speculated to have cost Ford millions of dollars in warranty repairs and buy backs. They led to many recalls and the repurchase of at least 500 trucks, particularly in the first year. However, aftermarket parts exist to address these issues and, with them installed, the 6.0L engine's reliability improves greatly.

Key specifications

• Fuel Injection system: Split Shot HEUI (Hydraulic Electronic Unit Injectors)
• Valve Train: OHV 4-valve
• Turbo configuration: Single Variable Vane Geometry (VGT)

Design problems

Intake & Exhaust

Some of the problems encountered, was the possibility of the variable geometry turbo charger to stick due to carbon deposits and/or rust buildup. This could potentially cause over boost and under boost conditions, which could lead to headgasket failure. Other problems include sticking exhaust gas recirculation valves, restricted oil coolers, which lead to leaking EGR coolers, and in turn blown headgasket.

• Carbon deposits can be an issue with any engine with EGR, but had a tendency to lead to a domino effect of problems for the 6.0.
• Most of the problems with the 6.0 were all caused by the domino effect. For example, Ford uses sand cast molds; the residual sand in the system would clog the oil cooler, in turn taking out the EGR cooler with it because both use coolant in their design to function properly. When the EGR cooler failed, it would pump coolant through the engine. If enough coolant entered the engine, it would stretch the head bolts allowing the head gaskets to blow. These trucks mainly got a bad reputation because of repeat failures. These repeat failures were due to improper service bulletins. When Ford first started experiencing problems with the EGR coolers, it was not standard procedure to also replace the oil cooler. This led to many repeat failures until Ford found the domino effect and implemented new standards for fixing the trucks.

Cylinder heads

The major problem with the 6.0L was the torque-to-yield head bolts, which in an overboost condition would lead to a blown head gasket, and eventually a cracked cylinder head. The 7.3L and 6.7L Power Stroke engines both have 6 head bolts per cylinder (as well as the 6.9L and 7.3L International Harvester IDI engines). By contrast, the 6.0L only has 4 head bolts per cylinder.

Electrical & Fuel

Numerous PCM recalibrations, fuel injector stiction along with several other driveability and QC problems have been problems for the 6.0 as well. The FICM (Fuel Injection Control Module) has been a problem.

6.4 Power Stroke

Main article: 6.4L Power Stroke

The 6.4 L PowerStroke replaced the 6.0 L due to new emission regulations for on-highway diesel engines built after January 1, 2007; in early 2007 Ford introduced its redesigned 2008 Super Duty with the new 6.4 liter engine as an option.

The new engine has a 3.86 in (98 mm) bore and 4.13 in (105 mm) stroke, resulting in a total calculated displacement of 387 cu in (6.3 L) or (6333 cc). Despite having to meet emission regulations, the new engine was able to increase horsepower and torque ratings to 350 hp (261 kW) and torque to 650 lb⋅ft (881 N⋅m) at the flywheel. Horsepower and torque are achieved at 3,000 rpm and 2,000 rpm respectively. It also features a dual sequential turbo system. The main components of this system are a smaller, non-wastegated turbo providing boost to a larger variable geometry turbo. This system is designed to result in reduced turbo "lag" when accelerating from a stop. The series-turbo system is set up to provide a better throttle response while in motion to give a power flow more like a Naturally aspirated engine. The 6.4 liter also has a Diesel Particulate Filter (DPF) and dual EGR coolers which are capable of reducing exhaust gas temps by up to 1000 degrees before they reach the EGR valve and mix with the intake charge. The Diesel Particulate Filter traps soot and particulates from the exhaust and virtually eliminates the black smoke that most diesel engines expel upon acceleration. The engine computer is programmed to periodically inject extra fuel (known as a "regeneration" in F-Series) to burn off soot that accumulates in the DPF. This engine must run on Ultra Low Sulfur Diesel (ULSD) fuel which has no more than 15 ppm sulfur content; using regular diesel fuel will result in emission equipment malfunctions and violate manufacturer warranties.

The 6.4L has had one recall (Safety product recall 07S49 was released on March 23, 2007) that addresses the potential for flames to come from the tailpipe of the truck. This problem arises from the DPF which is part of the diesel after-treatment system. A PCM recalibration has been released to eliminate the possibility of excessive exhaust temperatures combined with certain rare conditions resulting from what is becoming known as a "Thermal Event".

Key Specifications

• Fuel Injection System: High Pressure Commonrail
• Valve Train: OHV 4-valve
• Dual sequential turbochargers
• Diesel particulate filter

6.7 PowerStroke

The 6.7 L is the first medium duty diesel designed and built by Ford. It was designed in conjunction with AVL in Austria. During design, Ford engineers codenamed this engine "Scorpion" due to the turbo being mounted right on top of the block. It includes a compacted graphite iron (CGI) block for greater strength while reducing weight, reverse flow aluminum cylinder heads (the exhaust ports are located in the lifter valley) with dual water jackets, six head bolts per cylinder, and 29,000 psi (1,999 bar) a high-pressure common rail Bosch fuel system. The system delivers up to five injection events per cylinder per cycle using eight-hole piezo injectors spraying fuel into the piston bowl. This engine also supports B20 biodiesel (allowing greener fueling options of up to 20 percent biodiesel and 80 percent petroleum diesel). There is also a unique inboard exhaust and outboard intake architecture, an automotive-industry first for a modern production diesel engine. Honeywell’s single-sequential turbocharger features an industry-first double-sided compressor wheel mounted on a single shaft. It combines the benefits of a small turbocharger (faster response) and a large turbocharger (ability to compress and force more air into the engine for more power) in one unit. The connecting rods are made by Mahle.

Emissions controls include exhaust gas recirculation, Denoxtronic based Selective Catalytic Reduction (SCR) solution from Bosch, and a Diesel Particulate Filter (DPF). Output was originally 390 hp (291 kW) and 735 lb⋅ft (997 N⋅m). but shortly after production started, Ford announced that they have made an update to the new 6.7L diesel. The new engine control software makes the engine capable of 400 hp (298 kW) @ 2800 rpm and 800 lb⋅ft (1,085 N⋅m) @ 1600 rpm while achieving better fuel economy and without any physical changes to the engine. All 6.7L engines already shipped to dealerships or purchased by customers can be upgraded to Fords new specifications with a free software update available at Ford dealerships.

Key Specifications

• Fuel Injection System: High Pressure Commonrail
• Valve Train: OHV 4-valve
• Turbo configuration: Single Sequential Variable Vane Geometry (VNT)
• Diesel particulate filter
• Selective Catalytic Reduction

Applications

The Power Stroke engine has been used in the following applications.

F-Series Super Duty/Excursion Applications

• Mid-1994–2003 7.3 L
• Mid2003–Mid2007 6.0 L
• 2008–2010 6.4 L
• 2011– 6.7 L

E-Series Applications

• Mid-1994–2003 7.3 L
• 2004–2010 6.0 L

LCF (Low Cab Forward) Application

• 2005–2010 4.5 L

Other engines with the Power Stroke name

A 3.0L Diesel I4 engine used in South American models of the Ford Ranger uses the Power Stroke name. In the North American version of the 2014 Ford Transit, the 3.2L Duratorq TDCi inline-5 adopts the Power Stroke branding.

See also

• Ford engines
• Ford Triton engine

External links

• Powerstroke Diesel home page
• Navistar International
• Power Stroke Diesel Specs