7.3 Power Stroke Valve Cover Removal & Installation

On the 7.3 Power Stroke diesel, valve cover removal is required for various repair and diagnostic procedures. Removing the valve covers gains access to the glow plugs, fuel injectors, and the valve train components. Additionally, the valve cover gaskets incorporate a pass-through connector that connects the engine wiring harness to the glow plug and fuel injector wiring harness housed in the top of the cylinder head.

While such an arrangement may seem to impede simple repairs, such as replacing the glow plugs, the task of removing the valve covers is not terribly difficult. Gaining access to the valve covers is notably more time consuming on late model engines for the simple fact that these intercooled engines have more components. But again, removing the components and gaining access to the valve covers is not terribly difficult.

Keep in mind that an engine will be vulnerable to various forms of contamination while the valve covers are removed. Additionally, sockets and other small tools can easily fall into the oil drain passages cast into the cylinder head, which could prompt major disassembly to retrieve them. Take great care to keep tools secure and dust, grime, and debris out of the top of the cylinder head assemblies.

Valve Cover & Associated Parts List

Hoses, gaskets, vacuum lines, and even wiring components can become brittle and damaged when moved, removed, or repositioned. Thus, inspect components closely and replace parts as necessary. There are not many parts associated with valve cover removal that are required to be replaced, but the chart below identifies many of the commonly replaced components.

[1] - Component can be reused if not damaged; inspect closely
[2] - Clean component thoroughly before reinstallation
[3] - Early engines use use (2) connectors per valve cover, late engines use (1) connector; valve covers, valve cover harnesses, and valve cover connectors are therefore different
[4] - Component should not be reused after removed, highly recommend replacing part(s)
[5] - O-ring serviced in turbocharger reinstall kit
[6] - Highly recommend replacing engine oil and lube oil filter shortly after reinstalling valve covers; oil contamination probable

How to Remove the Valve Covers on a 7.3 Power Stroke Diesel

Note that the order of some of these steps is not important. In these procedures, it has also been assumed that maximum space is desired with no obstructions as not to impede any subsequent repairs; the valve covers can technically be accessed without removing every component outlined herein. The process is significantly easier on early engines (OBS trucks), so we've focused on a late model engine in a Super Duty chassis. On an OBS truck, just remove the intake tube between the turbocharger inlet and the air box.

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• Disconnect both negative battery terminals.
• Disconnect the driver side positive battery terminal.
• Remove the driver side battery from the battery tray.
• If applicable, remove the plastic engine cover

• Disconnect the air filter restriction sensor (filter minder) connector.
• Loosen the hose clamp for the intake tube at the CCV adapter (corrugated intake tube connecting the CCV adapter to the air filter box lid).
• Remove the air filter box lid and tube as one assembly.

• Remove the engine air filter.
• Disconnect the air filter housing air temperature sensor connector.
• Remove the series of mounting bolts at the bottom of the air filter housing.

• Remove the series of battery tray mounting bolts.
• Remove the air filter housing/battery tray assembly from the engine compartment.
• Note - removing the battery tray gives clear access to the cold-side intercooler tube boot at the charge-air-cooler outlet.

• Remove the driver side intercooler tube.
• Cover the intake "Y" plenum opening to prevent foreign objects from entering.

• Disconnect the MAP sensor connector and remove the hose from the sensor.
• Remove the passenger side intercooler tube. Note that the hose clamp(s) at the intercooler are easier to access with the passenger side battery removed, but removing the battery is ultimately optional.
• Cover the intake "Y" plenum opening to prevent foreign objects from entering.

• Completely loosen the primary engine harness connector retaining bolt with a 10 mm socket.

• Loosen the crankcase vent (doghouse) hose clamp at the base of the intake adapter. If the factory locking clamps are still in place, they will need to be cut to remove the hose.

• Remove the green hose from the turbocharger inlet tube by sliding it out of the hole in the tube.
• Remove the (2) crankcase vent adapter mounting bolts from the valve cover bracket.

• Loosen the hose clamp securing the turbocharger inlet tube to the turbocharger compressor inlet.

• Maneuver/rotate the CCV adapter so that the rubber elbow slides out of the barbed fitting on the bottom of the adapter, then remove the entire adapter and inlet hose from the engine compartment.

• Cover of plug the turbocharger compressor inlet to prevent foreign objects from unintentionally entering the housing.
• Disconnect the hose from the wastegate actuator (red hose, above and towards the firewall of the compressor inlet.

• Disconnect the primary engine wiring harness connector (retaining bolt was loosened completely in a previous step).
• Remove the (2) nuts from the valve cover mounting studs for the engine wiring harness connector bracket.

• Tilt and maneuver the connector bracket towards the engine valley and secure it to the driver side engine lift eye with a cable tie. This will keep the connector and bracket from interfering with the removal of the driver side valve cover.

• Disconnect the through valve cover harness connectors on both the driver and passenger sides.

• Remove the dipstick tube mounting stud nut on the passenger side, then slide the bracket over the stud and let it rest away from the passenger side valve cover.

• Optional - remove the oil fill tube from the top of the passenger side valve cover by rotating it counterclockwise until it releases. It tends to get in the way when navigating the valve cover bolts, but it is not required to be removed. Cover the hole in the top of the valve cover to prevent dropping a foreign object into the top of the cylinder head.
• As applicable, position the heater hose(s) traveling across the passenger side valve cover up and away from the valve cover with cable ties.

• The driver side valve cover bolts and studs are now accessible and can be removed with basic hand tools.
• Use compressed air to blow dust and debris from the edges of the valve cover and prevent foreign debris from falling into the cylinder head upon removal.
• Each fastener, whether a stud of bolt, requires a 13 mm socket or wrench.
• While the rearmost (closest to firewall) valve cover bolt is difficult to reach, a 1/4 inch drive ratchet with a shallow 13 mm socket will fit unless the ratchet has a large profile head.

• The passenger side bolts are and studs are now accessible and can be removed with basic hand tools.
• Use compressed air to blow dust and debris from the edges of the valve cover and prevent foreign debris from falling into the cylinder head upon removal.
• The fasteners closest to the heater box will need to be removed with a wrench as a ratchet will not fit. A ratcheting wrench makes quick work of these bolts. Note that the glow plug controller/IAH/glow plug relay bracket is secured with the top row of studs.

Valve Cover Reinstallation

Valve cover installation is exactly opposite the removal procedures. Valve covers and valve cover gaskets should be clean and free of debris before reinstalling. Install and tighten all mounting bolts/studs snug, then torque to 96 in-lbs in an alternating fashion. You will not be able to reach every bolt and stud with a torque wrench; torque what is accessible and tighten the remaining by feel. Note the small torque rating and do not over-tighten any of the fasteners as it may damage the valve cover gaskets.

The brackets for the main engine wiring harness connector (driver side, square plug), glow plug relay/IAH/glow plug controller, and dipstick tube are held in place by studs, not bolts. The correct location of the studs can be interpolated using the location and orientation of these components. There are a total of (10) fasteners for each valve cover. We recommend changing the engine oil and lube oil filter shortly after reinstalling the valve covers. It is probable that some amount of dust or fine debris infiltrated the top of the cylinder head when the valve cover was removed, which will contaminate the engine oil upon startup.