Because Diesels are a different breed of internal combustion engine, the common practice was to purchase a used engine from the local salvage yard instead of rebuilding one. But this has become a much harder task. Salvage engines were an easy replacement but they have become scarce. Not only are they getting harder to find but also the condition and mileage of the used engine may become a factor. Over the years of production, aftermarket companies have begun manufacturing parts necessary for their rebuilds.
To rebuild your Power Stroke, you will need some basic hand tools such as sockets and wrenches and also some specialty tools. Most of the hand tools are metric— 8, 10, 13, 15, 16, and 18 mm—and include sockets for 1/4-, 3/8-, and 1/2-inch-drive ratchets. Tool suppliers like Mac Tools, Snap-on, and Matco may have the specialty tools required to properly rebuild a Power Stroke.
This Tech Tip is From the Full Book, HOW TO REBUILD FORD POWER STROKE DIESEL ENGINES 1994-2007. For a comprehensive guide on this entire subject you can visit this link:
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For the 7.3 engine removal and disassembly, an older body style (1994 to 1997) was chosen for the step-by-step coverage in this book. Plenty of these trucks are still on the road today and many of them are in need of a rebuild or are certainly approaching that point. The only major issue in the engine removal of these year models is the radiator support. From 1999 to present, the radiator supports can be removed for easier access. But in the earlier 1994 to 1997 models, you simply have to work around the radiator support. The following step-by-step photos give you an idea of what is involved.
Step-1: Disconnect Battery
The first and most important thing to do is to disconnect the battery. The passenger side is exposed so start with this battery first. Remember to isolate the positive battery cable away from other metal objects until you can disconnect the driver side.
Step-2: Remove Intake Scoop
In order to disconnect the driver-side battery you have to remove the air cleaner intake scoop. This is usually held in place by a bolt with an 8-mm socket head.
Step-3: Drain Oil
Use a 3/4-inch wrench and drain the oil. If you perform your own oil changes this shouldn’t be a problem.
Step-4: Drain Antifreeze (Professional Mechanic Tip)
Drain the antifreeze. To keep it from dripping along the bottom of the lower radiator support, I install a small piece of 3/8-inch rubber fuel line to the drain nipple. This makes it easier and less messy to aim for the drain pan.
Air Inlet System
Step-1: Remove Air Cleaner Lid Bolts
Use a 1/4-inch-drive rachet with an extension to remove the plastic bolts that hold the top of the air cleaner lid in place. The 1/4-inch extension fits into the top of the plastic bolts.
Step-2: Loosen Hose Clamp
Loosen the clamp on the rubber hose coming from the turbo inlet pipe to the air cleaner assembly.
Step-3: Remove Bolts
Use a 10-mm socket to remove the bolts that hold the lower air cleaner box to the inner fender.
Step-4: Disconnect IAT Sensor
Disconnect the intake air temperature (IAT) sensor and remove the lower air cleaner assembly.
Step-5: Remove Battery Hold-Downs
Use an 8-mm socket to remove the battery hold-down bolts. Remove both batteries.
Step-6: Remove Radiator Hose
Remove the upper radiator hose by squeezing the top of the clamp together with a pair of pliers.
Front Belt Drive Accessories and Radiator
Step-1: Loosen Clutch Fan
While the serpentine belt is on the motor, take this opportunity to loosen the clutch fan from the water pump. The belt serves as an extra hand in the loosening process. (Remember, this should be done with a special wrench you can obtain from the local parts store for this application.) At this time do not fully remove the clutch fan from the water pump.
Step-2: Turn Belt Tensioner Pulley(Professional Mechanic Tip)
After loosening the clutch fan from the water pump, you can remove the drive belt by turning the belt tensioner pulley. The tensioner pulley is on a spring-loaded cam that applies tension to the belt. Place a 1/2-inch-drive rachet with a 15-mm socket on the bolt in the center of the pulley and turn.
Step-3: Loosen Belt
This is a view from the top of the radiator with the rachet and socket in position to loosen the belt.
Step-4: Remove Coolant Hoses
Use a pair of pliers to remove the clamps on the hoses at the coolant degas bottle. Remove the coolant hoses from the degas bottle.
Step-5: Remove Degas Bottle
Remove the bolts that hold the degas bottle to the passenger-side inner fender wheel using a 10-mm socket.
Step-6: Remove Clutch Fan and Fan Shroud
With an 8-mm socket, remove the two bolts at the top of the radiator that hold the fan shroud to the radiator. After removing these bolts, finish loosening the clutch fan from the water pump. Then remove the clutch fan and fan shroud together at one time.
Step-7: Remove Lower Radiator Hose
Remove the lower radiator hose from the water pump housing.
Step-8: Remove Radiator
Now the radiator can be removed. Using a 10-mm socket, remove the four bolts (two on each side) that hold the radiator to the radiator support.
Step-9: Disconnect and Remove Alternator
With the radiator removed, more engine components are exposed. Disconnect the wiring from the alternator. Using a 13-mm socket, remove the alternator from the engine bracket.
Step-10: Remove Pulley Bolt (Special Tool)
Remove the idler pulley below the alternator on the engine bracket. This is done by removing the bolt in the center of the pulley using a size-50 Torx bit socket.
Step-11: Remove Pulley
Next, the pulley from the tensioner can be removed. Using a 15-mm socket, turn the bolt in the pulley as though you were tightening it. The bolt in the pulley has a left-handed thread, so you are actually loosening the bolt.
Step-12: Remove Tensioner
Using the same size-50 Torx bit used to remove the idler pulley, you can now remove the tensioner from the engine bracket.
Step-13: Remove Engine Bracket
With the accessories and pulleys removed from the passenger-side engine bracket, you can now remove the engine bracket by removing the bolts with a 13-mm socket.
Step-14: Separate Connector
The engine wiring harness connector is on top of the driver-side valve cover. The connector is held together with a bolt in the center. As you loosen the bolt in the center with an 8-mm socket, the connector separates but the bolt does not fall out; the bolt is encased in the connector.
Step-15: Remove Vacuum Pump
The vacuum pump is on top of the driver-side engine bracket. Disconnect the vacuum line and remove the pump by removing the bolts that are located behind the pulley.
Step-16: Remove Pulley
Use a power steering pulley remover and installer tool to remove the pulley so you can gain access to the bolts that hold the power steering pump to the engine bracket.
Step-17: Remove Pump
Once the pulley is removed from the power steering pump, use a 13-mm socket to remove the bolts from the front of the pump. At this time you can lay the pump to the side without disconnecting any lines.
Step-18: Remove Bracket Bolts
Use a 13-mm socket to remove the bolts that hold the driver-side engine bracket to the engine.
Step-19: Remove Down Pipe Clamp
The exhaust down pipe that attaches to the turbo is right next to the firewall. At this time remove the clamp that holds the down pipe to the turbo and let it lay there.
Step-20: Loosen Down Pipe
This is how close the down pipe is to the firewall. At this time the pipe does not need to be removed, just loosened.
Step-1: Remove Ground Cable
At the front of the engine on the passenger’s side near the bottom of the block is a stud that supports the positive battery cable bracket and the ground cable. Using a 15-mm socket, remove the nut from the stud for the bracket. Once the bracket is off you can pull the stud and remove the ground cable.
Step-2: Remove Inlet Tube
The aluminum air inlet tube of the turbo is attached to a bracket that mounts to the driver-side valve cover. Use a 10-mm socket to remove the inlet tube from the bracket.
Step-3: Remove Rubber Tube (Professional Mechanic Tip)
Loosen the clamp of the rubber inlet tube at the turbo and remove the rubber tube. Here, where the rubber tube attaches at the turbo it has started to deteriorate and has started to come apart. After years of service, oil residue from the turbo tends to form a puddle in this bend of the inlet tube causing delamination.
Step-4: Remove Motor Mount Studs
Looking underneath (inside) the crossmember, use a 19-mm socket to remove the nuts from the studs of the motor mounts.
Step-5: Remove Starter
Remove the wires from the starter and, using a 17-mm socket, remove the starter.
Step-6: Remove Bellhousing Bolts
The exhaust pipe from the turbo tightly fits between the transmission and the body. Notice that the factory squeezed the pipe to gain clearance.
Using a 13-mm socket, remove the bolts from the transmission bellhousing. Remove torque converter bolts (automatic transmission). Use a floor jack to support the transmission while the engine is being removed.
Step-7: Remove Inlet Tube
Loosen the clamps that hold the inlet tube from the turbo compressor housing to the intake of the engine. Remove the tube and at this time attach a chain to the engine lift brackets.
Step-8: Remove Pedestal Bolts
Remove the two bolts in the front of the turbo-mounting pedestal with a 10-mm socket.
Step-9: Disconnect EBV
Disconnect the exhaust backpressure valve (EBV) electrical connection on the driver’s side at the bottom of the turbo compressor housing.
Step-1: Remove Front Turbo Housing Bolts (Professional Mechanic Tip)
Remove the bolts that connect the turbine housing of the turbo to the exhaust up-pipe manifold. This can be tricky! In order to make things easier, it may be in your best interest to remove the transmission because the bolts are nearly impossible to get out without breaking.
Step-2: Remove “Y” Manifold
Here’s a big challenge: The “Y” manifold has to come loose from the turbo before the turbo can be removed. The turbo has to come out before the engine can clear the windshield cowl panel.
Step-3: Remove Rear Turbo Housing Bolts
After the “Y” manifold has been removed from the turbo, remove the bolts from the rear of the turbo-mounting pedestal. Then the turbo can be removed from the engine.
Step-1: Remove Engine
For 1994 to 1997 models, removal and installation of the engine is a tight squeeze due to the design of the engine compartment. This doesn’t pose a real problem; just a little aggravation.
With a suitable hoist, remove the engine from the engine bay. Also, use a piece of 2 x 4 to wedge between the frame rails to support the transmission after the engine is removed.
Step-2: Place Engine on Stand (Save Money)
These engines weigh approximately 1,000 pounds. In order to support that kind of weight, you need a suitable engine stand rated for the appropriate capacity. This kind of stand can be very expensive because you have to be able to rotate the engine. An option is to build a support out of wood similar to this one so you can cradle the engine and remove many of the essentials, then move it to a budget engine stand to complete the teardown.
Step-1: Remove Lower Pipe Plugs
Once the engine is removed and still on the engine hoist, remove the pipe plugs in the lower portion of the block to drain the antifreeze. Do this before placing the engine on a cradle or appropriate engine stand. It will make the teardown less messy especially when removing the cylinder heads.
Step-2: Remove Oil Cooler Pipe Plug
In order to drain the antifreeze from the driver’s side of the block, you need to remove the pipe plug at the rear of the oil cooler using a 5/16-inch square-headed socket.
Step-3: Remove Wiring Harness
Remove the wiring harness from the engine.
Step-4: Disconnect Sensors
Remove the bolt from the harness clamp at the lower portion of the water pump on the passenger’s side. Disconnect the EBV sensor connectors and temperature sender connectors.
Step-5: Remove Relay Bracket Bolts
Remove the bolts that hold the glow plug relay bracket to the passenger-side cylinder head.
Step-6: Remove Engine Harness (Professional Mechanic Tip)
Unplug the rest of the sensors and remove the engine harness. With the engine harness removed, the highpressure hoses and fuel lines are now exposed and easier to access.
Step-7: Remove Oil Hoses From Cylinder Head
Remove the high-pressure oil hoses from the fittings of the cylinder heads.
Step-8: Remove Hose Clamp
On the driver-side cylinder head, remove the high-pressure hose clamp at the cylinder head underneath the fuel filter restriction sensor.
Step-9: Remove Oil Hoses From HPOP
Remove the high-pressure oil hoses from the HPOP.
Step-1: Remove Fuel Hoses
At the front of each of the cylinder heads are the fuel return hoses. Remove them from the fittings in the cylinder head.
Step-2: Drain Fuel from Filter Basket (Professional Mechanic Tip)
Below the passenger-side cylinder head near the oil pan is the metal line from the fuel filter basket for the water separation drain. Place a drain pan under the metal pipe and open the water separator valve on the fuel filter basket. This allows the fuel to drain from the filter basket.
Step-3: Remove Fuel Inlet Tubes
At the back of each of the cylinder heads are the fuel inlet tubes that branch together and join at a banjo fitting in the back of the fuel pump. Remove the fuel inlet tubes from the rear of each of the cylinder heads.
Step-4: Remove Fuel Inlet Branch
Now you can remove the fuel inlet branch from the back of the fuel pump by removing the banjo fitting.
Step-5: Remove Fuel Supply Hoses
Loosen the clamps of the rubber fuel supply hose at the fuel pump and rubber fuel return hose at the regulator attached to the fuel filter basket and remove the hoses.
Step-6: Remove Rubber Hose
Remove the rubber hose at the bottom of the fuel filter basket that connects the water separation drain to the metal tube.
Step-7: Remove Fuel Filter Basket Bolts
Remove the two bolts (one on each side) that hold the fuel filter basket to the engine block.
Step-8: Remove Fuel Pump and Fuel Basket (Important!)
Using a pry bar, gently lift up on the bottom of the fuel pump. Be careful, the fuel pump actuator rod that runs on the camshaft is sealed by an O-ring that can be stubborn to break free. If you get in too big of a hurry, the bottom of the fuel pump breaks off. Once the fuel pump is loose from the block, remove the fuel pump and fuel basket together at the same time.
Step-9: Remove Fuel Lines
Now you can remove the fuel supply and return metal lines that are fastened to the cylinder head with a clamp.
Step-10: Remove Crankcase Breather
Take a Phillips screwdriver and remove the screws that attach the engine crankcase breather to the valve cover.
Step-1: Remove Valve Cover Bolts
On the driver side valve cover, remove the two nuts that hold the wiring harness support bracket to the valve cover. Then remove the rest of the bolts that hold the valve cover to the cylinder head.
Step-2: Remove Valve Cover Gasket
The valve cover gasket of the 7.3 has the wiring harness for the injectors and glow plugs integrated into the gasket. In order to remove the gasket you need to disconnect the injector and glow plug harness.
Step-3: Remove Fuel Plug From Cylinder Head
Before the injectors are removed, there are several preventative things to do to create less mess. At this time the cylinder head still has oil in the high-pressure gallies and fuel surrounding each injector. Start by removing the fuel plug in the rear of the cylinder head with a 1/4-inch ratchet to drain the fuel from the cylinder head.
Step-4: Drain Oil Reservoir (Professional Mechanic Tip)
The easiest way to drain the high-pressure oil reservoir from each cylinder head is to remove the plugs in the reservoir from the front and rear of the cylinder head. You can accomplish this with a 1/2-inch-drive ratchet, but be warned. Most of these plugs cannot be removed unless you apply some heat to the cylinder head first. Before removing the plug have a drain bucket handy, because there will be quite a bit of oil that is going to come out from the reservoir of each cylinder head.
Step-5: Remove Injector Bolts
Using an 8-mm socket, remove the bolt in the center of the rocker arms below the injector. This bolt holds the injector to the cylinder head.
Step-6: Push Up on Injector Retaining Ring
Once the bolt is removed, push up on the injector retaining ring. This frees the retaining ring from the other bolt in the retaining ring in the upper cylinder head. The retaining ring is made to slide on this bolt once the bottom bolt is removed.
Step-7: Remove Injector
Now take a small pry bar under the retaining ring of the injector and pry up to remove the injector. Something I do is to mark which cylinder the injector came from.
Step-8: Store Injector Properly
Protect the injector by placing it in a gallon storage bag rather than just putting it into a box.
Step-9: Inspect Injector Hold-Down (Critical Inspection)
Look closely and you will notice how the upper bolt of the injector hold-down has fewer threads and more of a shoulder than the lower retaining bolt. Remember this when it is time to reassemble the engine.
Step-10: Remove Intake Manifold
At this time, you can remove the intake manifold from the driver-side cylinder head.
Driver-Side Cylinder Head
Step-1: Remove Rocker Arm
Using an 8-mm socket, remove the rocker arms from the cylinder heads and the pushrods (left). Use caution when removing the rocker arm. In the lower part of the rocker arm is the pivot ball (right), which can be easily lost.
Step-2: Remove Exhaust Manifolds
Next, remove the exhaust manifolds from the cylinder head using a 13-mm socket.
Step-1: Remove Water Pump Pulley Bolts
Next, let’s work on removing the front structure of the engine. Start by removing the bolts that hold the water pump pulley.
Step-2: Remove Return Pipe
Remove the heater core coolant return pipe from the top of the water pump.
Step-3: Loosen Feed Tube
Use a 9/16-inch wrench to hold the exhaust backpressure sensor while using a 5/8-inch wrench to loosen the tube that feeds the sensor from the passenger-side exhaust manifold.
Step-4: Remove Manifold Feed Pipe
Remove the exhaust backpressure feed pipe from the passenger-side manifold with a 5/8-inch wrench.
Step-5: Remove Exhaust Backpressure Sensor
Using a 1-inch wrench, remove the exhaust backpressure sensor from its bracket.
Step-1: Remove Window Cover Bolts
Remove the bolts to the small window cover using an 8-mm socket.
Step-2: Remove Window Cover
The factory seals this window cover with sealant, so use a small pry bar to remove the cover (left). Now the bolt for the HPOP is exposed (right).
Step-3: Remove Drive Gear Bolt
Use an 18-mm socket and an impact gun to remove the bolt that holds the drive gear to the HPOP.
Step-4: Remove HPOP Bolts
Looking at the rear of the HPOP, you will notice two bolts that hold the HPOP to the front cover (left). Using a 10-mm socket and extension, remove the bolts in the rear of the HPOP (right).
Step-5: Remove HPOP
The HPOP can be removed from the front cover of the engine (left). When the HPOP is removed, oil drains from the HPOP reservoir, which is in the top of the front cover (right).
Step-6: Remove HPOP Reservoir Bolts
On top of the front cover of the engine is the HPOP reservoir. Remove the bolts from the top and remove the reservoir from the front cover.
Step-7: Remove HPOP Drive Gear
After removing the reservoir, you can now remove the HPOP drive gear from the front cover.
Passenger-Side Cylinder Head
Step-1: Remove Dipstick Tube Bracket
Next, work on the passenger side. Start by removing the engine oil dipstick tube from the bracket on the valve cover.
Step-2: Remove Dipstick Tube
Once the dipstick tube is free from the bracket on the valve cover, pull the dipstick tube out of the oil pan.
Step-3: Remove Valve Cover
Now remove the rest of the bolts from the valve cover and remove the valve cover from the cylinder head.
Step-4: Remove Exhaust Manifold
Using an impact gun and a 13-mm socket, remove the exhaust manifold from the passenger-side cylinder head.
Step-5: Remove Glow Plugs
At this time, go ahead and remove the wiring harness, injectors, and glow plugs from the passenger-side cylinder head.
Step-6: Remove Cylinder Head Bolts
Using a 15-mm socket and an impact gun, remove the cylinder head bolts. Then you can remove the cylinder head. Be careful—the cylinder head is very heavy!
Step-7: Inspect Exhaust and Intake Valves (Important!)
After removing the cylinder head, take a look at the combustion side. You will notice that on the 7.3 the exhaust valve and intake valve are the same size. The intake valve is always identified by the “dimple” in the center of the valve. Remember this because the valves are not interchangeable.
Step-8: Remove Lifter Retaining Plate
Remove the lifter retaining plate so the lifters can be removed. Using a 13-mm socket, remove the bolts of the retaining plate carefully. Each bolt usually has a shim underneath it, which can be lost easily.
Step-1: Remove Clutch (Manual Transmission Only)
Now that the cylinder heads have been removed, use an engine hoist to raise the engine so it can be placed on an engine stand. Start by removing the clutch, if the engine is equipped with a manual transmission.
Step-2: Remove Flywheel
Next remove the flywheel or flexplate.
Step-3: Remove Adaptor Plate
At the rear of the engine an adaptor plate was used to adapt the International engine to a Ford transmission. The other way around? Go ahead and remove this also by sliding the adaptor plate off the dowels at the rear of the engine.
Remaining External Accessories
Step-1: Remove Oil Cooler
Using a 10-mm socket, remove the oil cooler from the engine. Two bolts at the front cover and three bolts at the rear of the block hold it on.
Step-2: Remove Motor Mounts
Remove the motor mounts from both sides of the engine using a 15-mm socket.
Step-1: Remove Oil Pan
Now it is time to work on removing the oil pan. There are only twelve bolts that hold the oil pan to the block. The problem is that there is no oil pan gasket, only sealer. This makes the oil pan difficult to remove. Gently pry along the rails of the oil pan the entire length of the block to loosen the sealer so the oil pan does not bend.
Step-2: Remove Oil Pump Pick-up Tube
When removing the oil pan you notice the oil pump pick-up tube. Remove the two bolts from the oil pump at the front cover and the support nut from the main bearing cap to remove the pick-up tube.
Step-3: Identify Each Connecting Rod (Documentation Required)
Before proceeding further, it is important to mark each connecting rod before it is removed from the cylinder. This identifies which cylinder it came from and also helps place the proper connecting rod cap with the right connecting rod. Each cap and rod are machined together, so if these become mixed up it causes a lot of problems. Use a set of machinist stamps and stamp the rod and cap as it faces the oil pan rail of that cylinder.
Step-4: Remove Connecting Rod Cap
The nuts of the connecting rod bolts are a 12-point design. Using a 12-point 11/16-inch socket, remove the nuts from the bolts that hold the cap to the connecting rod. Then remove the connecting rod cap.
Step-5: Remove Piston
Use the wooden handle of a hammer or a rubber mallet to push up on the connecting rod to move the piston out of the bore (left). Be careful not to hit the piston oilers that are placed in the bottom of the bores. This piston (right) had high oil consumption and some smoking. The rings were really stuck in the piston.
Step-6: Remove Harmonic Damper
Using an impact gun and a 15/16” socket, remove the bolt from the center of the crankshaft that supports the harmonic damper (left). After removing the bolt, you need a special tool to remove the damper (right). Remove the damper to gain access to the engine oil pump.
Step-7: Remove Oil Pump Bolts
After removing the damper from the crankshaft the engine oil pump is exposed on the front cover (left). The oil pump used on the 7.3 was a “gerotor” style. Remove the four bolts from the oil pump using a 10-mm socket (right).
Step-8: Remove Camshaft Position Sensor (Professional Mechanic Tip)
The camshaft position sensor is located above the engine oil pump on the passenger side of the front cover. Remove the sensor using a 10-mm socket. Be gentle; these sensors have an O-ring that may become hard and seal itself to the front cover. The best advice would be to remove the bolt and try to rotate the sensor inside the front cover by rotating the bracket while gently prying on the sensor.
Step-9: Remove Water Pump
Remove the bolts from the water pump and remove the water pump from the front cover.
Step-10: Remove Front Cover
There are only four bolts left holding the front cover, remove them with a 10-mm socket and remove the front cover to expose the camshaft.
Step-11: Remove Bypass Plug
The plug above the camshaft in the top of the engine block on the driver side is the oil short-circuit bypass plug. The bypass protects the HPOP reservoir during cold starts. Use a 3/8-inch ratchet and extension to remove the plug. Be careful because the plug is spring-loaded. Once the plug is removed, pull out the spring and the check ball inside the block.
Step-12: Remove Camshaft Bolts
The bolts that hold the cam thrust plate to the block are behind the windows of the camshaft gear. Rotate the engine to expose the cam bolts in order to remove them.
Step-13: Remove Camshaft (Important!)
Using a 15-mm socket, the main caps can now be removed from the engine so the crankshaft can be removed (above). Take note because the main caps come numbered from the factory along with an arrow indicating their location and their direction (right).
Step-14: Remove Piston Oilers
Next, the piston oilers need to be removed from the block. The oilers are located in the lifter valley of the engine. You need a 10-mm socket to remove the bolts that fasten them to the block.
Step-15: Remove Galley Plugs
The final thing that needs to be done is to remove all of the galley plugs before cleaning. There are two plugs above the camshaft at the front and rear of the engine. The rest of the plugs are at the base of the block at the oil pan on the driver’s side of the engine.
Written by Bob McDonald and Republished with Permission of CarTech Inc