Here you can find information regarding the assembly of the Ford 4.6L Modular engine. In this guide we will
start from the inside of the engine including the
crankshaft, connecting rods, and piston ring installation and then move outwards all the way to the pulley belt
system. Along the way correct procedures and torque specs
will be given to aid in the assembly of the engine. Feel free to start from the beggining and work your way
outwards or skip ahead to your current position in the engine for what you may need.
Crankshaft Main Caps Installation
The 4.6L modular engine block has 2 different methods of main cap fasteners. One of which is the Romeo styled
that uses jackscrews that screw into the caps from the side of the engine. The other
is a Windsor style that uses tapered dowel pins to fasten the main caps. It is important to know which ones your
engine has before assembly as there are differences between the two. The most significant
one being the thrust bearing washers.
Romeo Styled Main Caps
To install the Romeo main caps you must first install the caps and start by torquing them to 30 ft-lbs and then
an additional 90 degrees. Afterwards you can torque the jackscrews to 7 ft-lbs, then
the cross bolts to 15 ft-lbs starting from the center bolt and moving outwards.
Mustang Romeo Main Cap Torque Specs : 30 ft-lbs + 90°
To install the Windsor main caps you must first torque the main caps the same as the Romeo's being 30 ft-lbs and
then an additional 90 degrees. Afterwards you can hammer in the dowel pins into place
and then install the side cross bolts and torque to 24 ft-lbs and then an additional 90 degrees. All bolts
should be lubricated with oil before installing.
Mustang Windsor Main Cap Torque Specs : 30 ft-lbs + 90°
To install the pistons and connecting rods you must first install the piston rings into each piston. Be careful
not to stretch the rings or break them during installation. Make sure to put the correct rings in the correct
positions, this can be determined by looking at
the instructions given with the new rings. Each ring manufacturer is different so be sure to check for your
specific rings. Once the rings have been installed you can now fit the connecting rod bearings into the end caps
and lube them up with oil or lithium grease. The piston can now be lowered into the cylinder, make sure the dot
or mark is facing the front of the engine and that you don't scratch the cylinder.
Once installed you can match the connecting rod caps with the correct rods and start to torque the connecting
rod bolts to 25 ft-lbs and then an additional 90 degrees. After all are done rotate the crank
to ensure all pistons move smoothly in and out of their cylinders.
Mustang Connecting Rod Torque Specs : 25 ft-lbs + 90°
Oil Pump Installation
When installing the oil pump be sure to use the proper sealant around the pump base to ensure that oil pressure
doesn't drop due to leakage. After preparing the contact surfaces carefully
install the oil pump onton the crankshaft by aligning the crankshaft flat points with the pumps own points. Once
installed install the bolts and torque them to 8 ft-lbs. After torqueing the bolts be
sure to prime the pump with the proper engine oil, this ensures that when the engine is initially started that
oil is already present in the pump and that the engine doesn't start without any oil flowing
inside of it.
Mustang Oil Pump Torque Specs : 8 ft-lbs
Cylinder Head Installation
The first thing you must do when installing cylinder heads is to ensure both the block and head surfaces are
completely clean from dust, oil, and any debris. The next thing you must to is
to set the camshafts to their correct positions to prevent any valves from hitting pistons during installation
and torquing of the head bolts. Much the same you have to set the pistons to their correct
locations, typically this means putting the #1 piston to TDC or Top Dead Center. Once everything is ready you
can install the head gasket onto the engine block by aligning the alignment dowels.
Something I usually do is spray down the head gasket with some engine copper spray from permatex which you can
find here, this ensures that any gaps that could be present between the 2 surfaces gets filled with the
spray. It
also helps to transfer heat between the 2 metals. With the gasket in place you can set the cylinder head onto
the gasket and block, if needed have someone assist with this process as the head can be heavy
and you don't want to scratch anything or drop it! Once the head has been placed you will want to start
installing the head bolts to make sure it doesn't move. Be sure to buy new head bolts as many manufacturers
use TTY or Torque to Yield head bolts meaning they stretch during torqueing and cannot be used twice. Also make
sure to lubricate the bolts in clean engine oil before installing them into the head.
Once all the head bolts have been installed and finger tightened you can start the torqueing process, almost all
head bolts have a multi-step process for torqueing. The 4.6L starts off with 30 ft-lbs and
then an additional 90 degrees then requires you to back them off a full turn. Then you must again torque them to
30 ft-lbs and add 90 degrees then an additional 90 degrees for a total of 180 degrees after the
30 ft-lbs but by going through each bolt with each step. After torquing the heads are completely installed and
you can now move to intalling the timing.
To start with the timing chain installation you must first locate and install the timing gears in their correct
locations. In total you should have 5 gears included with the timing set. We will
start with the smaller 2 of the 5, the crankshaft timing gears. These gears slide onto the crankshaft starting
with the larger of the 2 with the shoulder side of the gears facing away from the engine or
towards the timing cover as shown in the picture. The next gears to install are the camshaft timing gears if you
haven't already when installing the cylinder head. The cam timing gears have a key slot cut
into them to ensure they are installed in the correct location. They are also marked L and R for left and right
and can be installed accrodingly onto the camshafts with the L one on the left hand side and
the R on the right hand side. Once placed you can install the retaining bolts into the camshafts and torque them
to 85 ft-lbs if they are M12 or 30 ft-lbs and then 90 degrees if they are M10's while also
holding onto the camshaft with a large wrench or crescent wrench to avoid it from moving. With the gears
installed you can now place the timing chains onto the gears starting with the further back one.
Be sure to align the painted marks on the chain to the dotted marks on the gears. Once you have both of the
chains installed correctly you can now install the timing chain guides in their correct
positions with the adjustable one on the tensioner side as shown in the picture. The chain guides torque specs
are 18 ft-lbs, with all the guides installed you can now preload the tensioner and install it
onto the engine block. The tensioners torque specs are the same as the guides being 18 ft-lbs. With them torqued
into place you can now release the preloaded spring and allow it to tension the chains.
Now you can install the 5th gear or the reluctor wheel onto the crankshaft. This is an important step of the
process as it tells the sensors which position the crank is currently in.
The timing cover on the 4.6L is rather large and is a very important component that keeps the oil insdie the
engine rather than leaking out onto the ground. For this reason I recommend using a new
gasket along with some silicone sealant to ensure the cover does it's job. Another important thing about the
timing cover is that it holds the crankshaft seal into place. Be sure to check out your seal
for any defects and or cracks. If your seal looks to be in good condition then you can reuse it without a
problem as long as you coat it with some clean engine oil before installing the cover. To prepare
the cover for installation you should clean both the cover's surface as well as the engine blocks surface. Next
you can install the new gasket onto the cover and follow it up with some silicone sealant.
I always use permatex's ultra black silicone sealant as it has an advance formula to resist engine oil. Once the
gasket and silicone has been placed onto the cover you can carefully place it onto the block
and start to install the cover bolts. If you used sealant be sure to follow the instructions included with the
product for the best results! There are two types of cover bolts, the ones that screw into the
engine block and the ones that screw into the cylinder head. The ones that go into the block torque to 20 ft-lbs
while the ones that go into the cylinder head torque to 35 ft-lbs.
Mustang Timing Cover to Block Torque Specs : 20 ft-lbs
Mustang Timing Cover to Head Torque Specs : 35 ft-lbs
Oil Pan Installation
Much like the timing cover on the 4.6L the oil pan plays an important role in keeping the engine oil inside the
engine. For this reason I recommend using a new gasket as well as some silicone sealant
during installation. Using the same technique as before with the cover you clean the surfaces of both the oil
pan and the engine block and then install the new gasket onto the block and then follow
it up with some silicone sealant. Be sure to follow your sealants instructions to ensure you get the best seal
from your application. The oil pan bolts torque to 15 ft-lbs and then an additional 60 degrees in a cross
patterns design.
Along with the pan is the oil pan drain plug, this gets removed and reinstalled quite frequently and can be
torqued down to 10 ft-lbs.
Mustang Oil Pan Torque Specs : 15 ft-lbs + 60°
Mustang Oil Drain Plug to Head Torque Specs : 10 ft-lbs
Valve Covers Installation
The valve cover installation is rather simple, there are rubber seals for each bolt hole and a silicone gasket
that prevents oil from leaking out of the engine. It is recommended to replace both the seals
and the gaskets although if they are in good condition you can reuse them. If you do choose to reuse them I
would use some silicone sealant along with the silicon gasket to ensure it does not leak.
The valve cover bolts torque down to 106 in-lbs or about 9 ft-lbs in a criss cross order. Be sure not to miss
any bolts to avoid having oil leak out onto the exhaust pipes and cause a lot of smoking.
Mustang Valve Cover Torque Specs : 9 ft-lbs
Intake Manifold and Fuel Rail Installation
When installing the intake manifold you want to make sure you have all the surfaces as well as intake holes
cleaned out before placing the manifold into position. Once cleaned you can then place
the intake manifold gaskets onto the alignment pins. If you want you can also use a little bit of sealant on the
gaskets to help ensure there are no leaks. With the gaskets in place you can now put
the manifold down onto the gaskets and begin to install the bolts. The intake manifold bolts torque to 18 ft-lbs
and can be tightened starting from the inside and going outwards. The COPs or the coils
for the spark plugs get torqued down to 60 in-lbs or about 5 ft-lbs and the spark plugs themselves can be
torqued down to 15 ft-lbs, be careful not to overtorque these as they can snap and cause big problems.
When installing the fuel rail make sure that all the fuel injectors are in good condition and that all the
o-rings are in place and
are in good condition. If everything is good you can place the fuel rail into position and push the injectors
into their holes and start to torque the rail bolts to 90 in-lbs or about 8 ft-lbs.
Mustang Intake Manifold Torque Specs : 18 ft-lbs
Mustang Ignition Coil Torque Specs : 5 ft-lbs
Mustang Spark Plug Torque Specs : 15 ft-lbs
Mustang Fuel Rail Torque Specs : 8 ft-lbs
Exhaust Manifold Installation
The exhaust manifold can be installed by cleaning the surface areas on both the head an the manifold itself and
then by using the exhaust manifold gasket and putting it in place. Once the gasket is in
location you can put the manifold onto the heads and begin to torque the bolts to 18 ft-lbs. I always use some
copper spray from permatex on the exhaust manifold gaskets to ensure I do not end up with
any exhaust leaks once done. When you go to install the engine into the vehicle or if it is already in the
vehicle the torque specs for the exhaust manifold to the exhaust pipes is 25 ft-lbs.
Mustang Exhaust Manifold Torque Specs : 18 ft-lbs
Mustang Exhaust Pipe Torque Specs : 25 ft-lbs
Water Pump and Thermostat Installation
The water pump can be installed by using a new gasket and if desired some silicone sealant to aid it. Once
prepared the pump can be moved into placed and the bolts should be torqued to 20 ft-lbs.
The water pump pulley can be torqued to the water pump itself with 20 ft-lbs as well.
Mustang Water Pump Torque Specs : 20 ft-lbs
Mustang Water Pump Pulley Torque Specs : 20 ft-lbs
Front Dress and Pulley belt Installation
Most of what is left on the engine is just place and tighten objects such as the belt pulleys, belt tensioner,
throttle body, oil filter neck, crankshaft pulley, and motor mounts. If the items have a gasket and hold either
oil or coolant inside the engine then feel free to add some sealant along with the gasket. Always be sure to
inspect your gaskets and replace them if there is any deteriation or flaws with them. Before
installing the belt system you can install the oil filter neck that is used for installing new oil filters. This
part should have a new gasket and can be torqued down to 20 ft-lbs. For the
belt system the crank shaft pulley gets torqued to 35 ft-lbs and then an additional 90 degrees. The belt
tensioner and idler pulley can both be torqued down to 20 ft-lbs. When installing be sure they
both turn smoothly and if they do not then replace them with new ones as the bearings can go bad. The engine
motor mount can be installed onto the engine block if it hasn't been already, the torques for
the mount to the block is 30 ft-lbs and then when installing the mount to the vehicle it can be torqued anywhere
from 95-125 ft-lbs. Finally the throttle body can be installed on top of the intake manifold
with a good gasket and some added sealant using 7 ft-lbs in a criss cross pattern. For installing the belt you
can use a tool to move the tensioner into its springed state and install the belt as shown in the
picture.
