1991 1999 ford explorer chilton User Manual

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If equipped, install the oil baffle.
5. 
Install rocker arm shaft assembly to the cylinder head and guide adjusting screws on to the pushrods.
6. 
Install and tighten rocker arm stand attaching bolts to specification, two turns at a time, in sequence
(from middle of shaft to the end of shaft).
7. 
Adjust the valve lash to the cold specified setting. Refer to Section 1 under Valve Lash Adjustment
for procedures.
8. 
Install the valve rocker arm covers.
9. 
DISASSEMBLY & REASSEMBLY Remove...

Disconnect the heater return hose at the thermostat housing located on the left front lower side of
engine.
2. 
Remove the coolant outlet housing retaining bolts and slide the housing with the hose attached to one
side.
3. 
Remove the thermostat from the outlet.
4. 
Remove the gasket from the engine block and clean both mating surfaces.
5. 
It is good practice to check the operation of a new thermostat before it is installed in an engine. Place
the thermostat in a pan of boiling water. If it does not...

Thermostat installation for the 3.0L engine
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Remove the upper radiator hose.
3. 
Remove the thermostat housing bolts.
4. 
Remove the housing and thermostat as an assembly.
5. 
Remove the thermostat from the housing.
6. 
To install: Clean all gasket material from the housing and engine.
7. 
Turn the thermostat clockwise into the housing until the thermostat bridge is perpendicular to the
mounting holes.
8. 
Position the housing on the engine, using a new gasket coated with sealer. Tighten...

Exploded view of the thermostat housing for the 4.0L engine-2.9L engine is similar
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To remove the thermostat, first remove the upper radiator hose, then the three attaching screws HOW TO USE THIS BOOK
REMOVAL & INSTALLATION 277 

Pull the thermostat housing from the intake manifold ...
... then remove the thermostat
Ensure that the sealing ring is properly seated. Install the thermostat with the release valve facing upwards
Remove the 3 thermostat housing attaching bolts.
5. 
Remove the thermostat housing. You may have to tap it loose with a plastic mallet or your hand.
6. 
Pull the thermostat from the intake manifold.
7.  HOW TO USE THIS BOOK
278 REMOVAL & INSTALLATION 

To install:
WARNING
Do not use a sharp metal tool for scraping. Damage to the sealing surfaces could result and cause a leak.
Clean all mating surfaces thoroughly.
8. 
Make sure that the sealing ring is properly installed on the thermostat rim. Position the thermostat in
the housing making sure that the air release valve is in the up(12 oclock) position.
9. 
Coat the mating surfaces of the housing and engine with an adhesive type sealer. Position the new
gasket on the thermostat and place the housing on...

To install:
WARNING
Do not use a sharp metal tool for scraping. Damage to the sealing surfaces could result and cause a leak.
Align the air bleed hole on the thermostat with the notch in the housing, which is also the 12 oclock position
Clean all mating surfaces thoroughly.
7. 
Position the thermostat in the housing making sure that the air release valve is in the up(12 oclock)
position.
8. 
Coat the mating surfaces of the housing and engine with an adhesive type sealer. Position the new
gasket on the...

Exploded view of the upper and lower intake manifold assemblies on the 2.3L and 2.5L engine
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The intake manifold is a two-piece (upper and lower) aluminum casting. Runner lengths are tuned to optimize
engine torque and power output. The manifold provides mounting flanges for the air throttle body assembly,
fuel supply manifold, accelerator control bracket and the EGR valve and supply tube. A vacuum fitting is
installed to provide vacuum to various engine accessories. Pockets for the fuel...

Disconnect the negative battery cable and secure it out of the way.
2. 
Remove the fuel filler cap to vent tank pressure. Release the pressure from the fuel system at the fuel
pressure relief valve using EFI pressure gauge T80L-9974-A or equivalent. The fuel pressure relief
valve is located on the fuel line in the upper right hand corner of the engine compartment. Remove the
valve cap to gain access to the valve.
3. 
Label and unplug any electrical connectors related to the intake manifold assemblies...

Loosen the clamp on the coolant bypass line at the lower intake manifold and disconnect the hose.
9. 
Disconnect the EGR tube from the EGR valve by removing the flange nut.
10. 
Upper intake manifold removal on the 2.3L and 2.5L engine Click to enlarge
Remove the upper intake manifold retaining nuts. Remove the upper intake manifold and throttle
body assembly.
11. 
If you only need to remove the upper intake manifold, stop at this point. Otherwise, continue with the
procedure to also remove the lower...