Because of the design of the rotary engine, it is not practical
to attempt component removal and installation. It is best to disassemble and
assemble the entire engine, or go as far with the disassembly and assembly
procedure as needed.
CARBURETED ENGINE
Remove the engine from the vehicle and mount on a suitable stand or
holding fixture.
To simplify reassembly, mark or label all components before
disassembly.
Remove the oil hose support bracket from the front housing.
Disconnect the vacuum hoses and air hoses, then remove the decel valve.
Remove the air pump and drive belt. Remove the air pump adjusting bar.
Remove the alternator and drive belt.
Disconnect the metering oil pump connecting rod, oil tubes and vacuum
sensing tube from the carburetor.
Remove the exhaust manifold cover, if equipped. Remove the carburetor and
intake manifold as an assembly.
Remove the gasket and two rubber O-rings.
Remove the thermal reactor/exhaust manifold and gaskets. Remove the engine
mount.
Remove the distributor.
On 1984-85 models, disconnect and remove the oil cooler assembly, as
described earlier in this section. Do not remove the oil filter from the
cooler housing unless replacement is desired.
Unbolt the A/C compressor pulley and remove the water pump.
FUEL INJECTED ENGINE
Non-Turbo
Remove the engine from the vehicle and mount on a suitable stand or
holding fixture.
To simplify reassembly, mark or label all components before
disassembly.
Remove the air conditioning compressor and the power steering pump
bracket.
Remove the left engine mount, spark plugs, oil level dipstick, oil filler
pipe, oil filter and filter body.
Remove the oil pressure gauge and distributor/crank angle sensor.
Remove the air pump, drive belt, and air pump bracket.
Remove the alternator and drive belt.
If so equipped, remove the clutch cover and clutch disc.
Remove the metering oil connecting rod, second vacuum piping, and
throttle/dynamic chamber.
Remove the primary fuel injector and distribution pipe.
Remove the air control valve, switching actuator, water pipe and air hose.
Remove the housing oil nozzle and manifold oil nozzle, intake manifold,
exhaust manifold and insulator.
Remove the metering oil pump, eccentric shaft pulley, and water pump.
Remove the dynamic chamber bracket, engine harness and vacuum piping, and
finally, the oil inlet pipe.
Turbo
Remove the engine from the vehicle and mount on a suitable stand or
holding fixture.
To simplify reassembly, mark or label all components before
disassembly.
Remove the air conditioning compressor and the power steering pump
bracket.
Remove the left engine mount, spark plugs, oil level dipstick, oil filler
pipe, oil filter and filter body.
Remove the oil pressure gauge and crank angle sensor.
Remove the air pump, drive belt, and air pump bracket. Remove the
alternator and drive belt.
If so equipped, remove the clutch cover and clutch disc.
Remove the metering oil pump connecting rod, secondary vacuum piping, and
throttle/dynamic chamber.
Remove the primary fuel injector and distribution pipe. Remove the air
control valve, switching actuator, water pipe, turbocharger with insulator,
and the air hose. Cover the intake and exhaust port openings of the
turbocharger with masking tape to prevent the entry of dirt and foreign
matter.
Remove the housing oil nozzle and manifold oil nozzle, intake manifold,
exhaust manifold and insulator.
Remove the metering oil pump, eccentric shaft pulley, water pump, dynamic
chamber bracket, engine harness and vacuum piping, and finally, the oil inlet
pipe.
Disassembly of Internal Components
ALL ROTARY ENGINES
Invert the engine.
Remove the oil pan retaining bolts. Remove the oil pan and the oil
strainer. It may be necessary to drive a scraper with a blade at least 1.2 in.
(30mm) wide and 0.06-0.08 in. (1.5-2.0mm) thick between the pan and the rear
housing to free the pan. Be very careful not to damage the housing or the pan
while removing.
Remove the oil strainer and gasket.
Oil pressure control valve
assembly
Front cover assembly
Oil pump drive assembly
Balance weight and bearing housing assembly-1979-85
RX-7
Balance weight assembly-1986-89
RX-7
Rotary engine tension bolt loosening
sequence
It will be necessary to lock the flywheel/flexplate to remove the pulley
from the front of the eccentric shaft. For manual transmissions, Mazda offers
a brake device (tool number 49-1881-060 or equivalent for earlier models, and
tool number 49-FO11-101 or equivalent for later models). For automatic
transmissions, Mazda offers a stopper which fits on the counterweight (tool
number 49-1881-055 or equivalent). With the flywheel/flexplate locked, remove
the bolt from the eccentric shaft pulley and remove the pulley.
Identify the front and rear rotor housings with a felt tip pen. These are
look-alike parts and must be identified to be assembled in their respective
locations.
Turn the engine on the stand so that the top of the engine is up.
Remove the engine mounting bracket from the front cover.
Remove the eccentric shaft pulley. On 1986-89 models, remove the eccentric
shaft bypass valve and spring. On 1985-89 models, remove the O-ring from the
eccentric shaft lockbolt and discard it. Remove the eccentric shaft pulley
boss (1986-89). Turn the engine on a stand so that the front end of the engine
is up.
On 1986-89 models, unscrew and withdraw the oil pressure control valve and
actuating spring from the bore in the front cover. Unbolt and remove the front
cover with the gasket. Slide the distributor drive gear from the eccentric
shaft. The gear is retained with a key. Remove the key from the keyway and
tape it to the gear.
Remove the O-ring from the oil passage on the front housing.
Remove the oil slinger and distributor drive gear from the shaft.
Unbolt and remove the chain adjuster.
Rotor, apex and side seals are identified by a number
which corresponds to the number on each rotor face seal
groove
If a seal sticks to the housing during removal, put it
back on the rotor
Rotor side seals
Removing the rotor from the intermediate
housing
Remove the locknut and washer from the oil pump driven sprocket.
Slide the oil pump drive sprocket and driven sprocket, together with the
drive chain, off the eccentric shaft and oil pump, simultaneously.
Detach the baffle plate from the oil pump (turbocharged engines only).
Remove the keys from the eccentric and oil pump shafts. Remove the oil pump.
Slide the balance weight, thrust washer and needle bearing from the shaft.
Unbolt the bearing housing, then slide the bearing housing, needle
bearing, spacer and thrust plate off the shaft.
Turn the engine on the stand so that the top of the engine is up.
If equipped with a manual transmission, remove the clutch pressure plate
and clutch disc. Remove the flywheel with a puller. Remove the key from the
shaft.
If equipped with an automatic transmission, remove the drive plate. Remove
the counterweight. Block the weight and remove the mounting nut. Remove the
counterweight with a suitable puller. On 1986-89 engines, remove the
counterweight stopper.
Working at the rear of the engine, loosen the tension bolts evenly in
small stages to prevent distortion. Mark the tension bolts to replace in their
original holes during reassembly.
When removing the tension bolts, refer to the appropriate
removal illustration. 1984-85 carbureted engines do not have a No. 6 tension
bolt, so delete that bolt from the illustration if it is not applicable.
Lift the rear housing off the shaft.
Remove the intermediate housing while applying upward
pressure to the eccentric shaft
Use a special tool to remove the rotor outer oil
seal
Remove any seals that are stuck to the rotor sliding surface of the rear
housing and reinstall them in their original locations.
Remove all the corner seals, corner seal spring, side seal and side seal
springs from the rear side of the rotor. Mazda has a special tray which holds
all the seals and keeps them separated to prevent mistakes during reassembly.
Each seal groove is marked with numbers near the grooves on the rotor face to
prevent confusion.
Remove the two rubber seals, two O-rings or oil seal from the rear rotor
housing. Remove the pressure regulator and the rear rotor housing side pieces.
Remove the tubular dowels from the rear rotor housing using puller tool
49-0813-215A or equivalent.
Lift the rear rotor housing away from the rear rotor, being very careful
not to drop the apex seals on the rear rotor. Remove the O-ring from the upper
dowel hole.
Remove each apex seal, side piece and spring from the rear rotor and
separate them accordingly.
Remove the rear rotor from the eccentric shaft and place it upside down on
a clean rag. Do not place the rotor on a hard surface.
Remove each seal and spring from the other side of the rotor and separate
them.
If some of the seals fall off the rotor, reinstall being careful not to
change the original position of each seal.
Identify the bottom of each apex seal with a felt tip pen.
Remove the oil seals and the spring. The outer oil seal is removed with
the use of special tool 49-0813-225 or equivalent. Do not exert heavy pressure
at only one place on the seal, since it could be deformed. Replace the O-rings
in the oil seal when the engine is overhauled.
Hold the intermediate housing down and remove the dowels from it using an
appropriate pulling tool.
Lift off the intermediate housing, being careful not to damage the
eccentric shaft. Slide the intermediate housing beyond the rear rotor journal
on the eccentric shaft, while pushing the eccentric shaft up. Lift out the
eccentric shaft.
Repeat to remove the front rotor housing and front rotor.
CLEANING
Front, Rear and Intermediate Housings
Remove carbon from the housings with extra fine emery paper. If
you use a carbon scraper, be very careful not to damage the finished surfaces of
the housing. Remove the sealant remnants with a cloth or brush soaked in a
solution of ketone or thinner.
Rotor Housing
Remove carbon from the inner surface of the rotor housing by
wiping it off with a cloth. Soak the cloth in a solution of ketone or thinner,
if the carbon is difficult to remove. Rust deposits should be carefully removed
from the cooling water passages on the housing. Remove sealant remnants with a
cloth or brush soaked in ketone or thinner. Be careful not to remove the felt
tip pen marks made while disassembling the engine.
Clean the rotor housing using a clean cloth which has
been soaked in solvent
Rotor
Remove carbon with a carbon remover or extra fine emery paper.
Clean the rotor in a standard cleaning solution and blow dry with compressed
air.
WARNING
Do not use emery paper on the apex or side seal
grooves. The side surfaces are coated with a very soft material. Do not
use excessive pressure on these surfaces while cleaning. Lightly polish
them.
Seals and Springs
Gas seals can be cleaned in a standard cleaning solution. Never
attempt to clean seals with emery paper or you will ruin them. Be careful not to
damage the seals or springs while handling them. Do not mix up the seals and
springs when cleaning.
Eccentric Shaft
Immerse the shaft in cleaning solution and blow the oil passages
dry with compressed air. Apply a light film of clean engine oil to the shaft to
prevent rusting.
INSPECTION AND COMPONENT REPLACEMENT
Front, Intermediate and Rear Housings
Check the housing for signs of gas or water leakage.
Remove the sealing compound from the housing surface with a cloth or brush
soaked in solvent or thinner.
Remove the carbon deposits from the front housing with extra fine emery
cloth. When using a carbon scraper, take extra care not to damage the surface
of the housing.
Check for distortion by placing a straightedge on the surface of the
housing. Measure the clearance between the straightedge and the housing with a
feeler gauge. If the clearance is greater than 0.0016 in. (0.04mm) at any
point, replace the housing.
Check the rotor housings for warpage along these
lines
Checking for housing wear with a dial indicator and
gauge body
Measuring stepped wear at the sides of the
housing
Measuring stepped wear across the middle of the
housing
Measuring stepped wear caused by the oil
seal
Use a dial indicator with a sled attachment (gauge body) to check for wear
on the rotor contact surfaces of the housing. Mazda offers such an attachment
under part number 49-0727-570 or equivalent. To check for stepped wear on the
rotor housing sliding surfaces, mount the dial indicator on the sliding
surface of the housing. To measure stepped wear caused by the side seal at the
sides of the housing, move the dial indicator gauge feeler to and fro as shown
in the illustration. The wear limit is 0.0039 in. (0.10mm). Check the side
seal stepped wear across the middle of the housing with the dial indicator,
moving it as shown in the illustration. The wear limit inside the oil seal
tracing marks is 0.0004 in. (0.01mm), and the wear limit outside the oil seal
tracing marks is 0.0039 in. (0.10mm). Check for stepped wear by the oil seal
with the dial gauge. The wear limit is 0.0008 in. (0.02mm).
If the front, intermediate and/or rear side housings are beyond the above
wear limits, they can be ground if the required finish can be maintained. If
the wear is greater than the values provided above, replace the housing.
The wear at either end of the minor axis is greater than at any
other point on the housing. However, this is normal and should not be cause for
concern.
Front Stationary Gear and Main Bearing
Examine the teeth of the stationary gear for wear or damage.
Be sure that the main bearing shows no signs of excessive wear, scoring,
or flaking.
Check the main bearing-to-eccentric journal clearance by measuring the
journal with a vernier caliper and the bearing with a pair of inside calipers.
The standard clearance is 0.0016-0.0031 in. (0.04-0.08mm). If the clearance
exceeds the limit, replace the front main bearing as described later in this
section.
Front Main Bearing Replacement
Unfasten the securing bolts, if used. Remove the stationary gear and main
bearing assembly from the housing, using puller tool 49-0813-235 or
equivalent.
Press the main bearing out of the stationary gear.
Press a new main bearing into the stationary gear, so that it is in the
same position as the old one.
Align the slot in the stationary gear flange with the dowel pin in the
housing, then press the gear into place. On later engines, align the bearing
lug with the slot in the gear. Install the securing bolts, if applicable.
Rear Stationary Gear and Main Bearing
Inspect the rear stationary gear and main bearing in a similar
manner to the front. In addition, examine the O-ring, which is located in the
stationary gear, for signs of wear or damage. Replace the O-ring, if necessary.
If the stationary gear must be replaced, follow the rear main bearing
replacement procedure.
Rear Main Bearing Replacement
Remove the rear stationary gear securing bolts.
Drive the stationary gear out of the rear housing with a brass drift.
Apply a light coating of grease to a new O-ring and fit it into the groove
on the stationary gear.
Apply sealer to the flange of the stationary gear.
Install the stationary gear on the housing so that the slot on its flange
aligns with the pin on the rear housing. On later engines, align the bearing
lug with the housing slot. Use care not to damage the O-ring during
installation.
Tighten the stationary gear bolts evenly, in several stages, to 12-17 ft.
lbs. (16-23 Nm).
Rotor Housings
Examine the inner margin of both housings for signs of gas or water
leakage.
Wipe the inner surface of each housing with a clean cloth to remove the
carbon deposits.
Clean all of the rust deposits out of the cooling passages of each rotor
housing.
Checking rotor housing width
Remove the old sealer using the proper removal solvent.
Examine the chromium-plated inner surfaces for scoring, flaking, or other
signs of damage. If any are present, the housing must be replaced.
Check the rotor housings for distortion by placing a straightedge on the
axes.
If distortion exceeds 0.002 in. (0.05mm), replace the rotor housing.
Check the widths of both rotor housings, at points A, B, C, and D near the
trochoid surfaces of each housing, using a vernier caliper, as illustrated.
Compare the difference between the value obtained at point A and the minimum
value of points B, C and D. If the difference between the values obtained is
greater than 0.0024 in. (0.06mm), replace the housing. A rotor housing in this
condition will be prone to gas and coolant leakage.
Rotors
Check the rotor for signs of blow-by around the side and corner seal
areas.
The color of the carbon deposits on the rotor should be brown, just as in
a piston engine. Usually, the carbon deposits on the leading side of the rotor
are brown, while those on the trailing side tend toward black (as viewed from
the direction of rotation).
Remove the carbon on the rotor with a scraper or extra fine emery paper.
Use the scraper carefully when cleaning the seal grooves to avoid any damage.
Wash the rotor in solvent and blow it dry with compressed air.
Checking rotor width
Examine the internal gear for cracks or damaged teeth. If the internal
gear is damaged, the rotor and gear must be replaced as a single assembly.
With the oil seal removed, check the land protrusions by placing a
straightedge over the lands. Measure the gap between the rotor surface and the
straightedge with a feeler gauge.
Check the clearance between the housings and the rotor on both of its
sides:
Measure the rotor width with a vernier caliper at the points indicated
in the corresponding illustration.
Compare the rotor width against the width of the previously measured
rotor housing.
Replace the rotor, if the difference between the two measurements is not
0.0047-0.0074 in. (0.12-0.19mm) for the 1979-85 carbureted engine or
0.0047-0.0083 in. (0.12-0.21mm) for the 1984-90 fuel injected engine.
If the clearance exceedsthe specified values, replace the rotor. If the
clearance is lessthan specification, it means that the internal gear must be
removed. To dislodge the gear from the rotor bore, smack it lightly with a
plastic-faced hammer, being careful not to damage the rotor. With the gear
removed, recheck the side housing-to-rotor clearance again.
The corner seal bores can be checked with a gauge (tool number 49 0839 15
or equivalent), available from Mazda. If neither end of the gauge can be fit
into the bores, it is safe to reuse the original corner seals. If the "go"
side of the gauge does fit into the bore, but the larger "no go" side does
not, use new seals. If both sides of the gauge fit into the bores, the rotor
must be replaced.
Check the rotor bearing for wear, flaking, scoring or damage. Replace the
bearing if these conditions are found. Check the bearing oil clearance by
measuring the appropriate bearing journal diameter on the eccentric shaft with
a micrometer. Next, measure the inner diameter of the rotor bearing.
The standard rotor bearing journal diameter is 2.913 in.
(74mm).
Find the oil clearance by subtracting the rotor bearing diameter from the
rotor journal diameter. The standard clearance is 0.0016-0.0031 in.
(0.04-0.08mm). If the clearance is greater than 0.0039 in. (0.10mm), replace
the rotor bearing as described later in this section.
Rotor Bearing Replacement
Check the clearance between the rotor bearing and the rotor journal on the
eccentric shaft. Measure the inner diameter of the rotor bearing and the outer
diameter of the journal. The wear limit is 0.0039 in. (0.1mm); replace the
bearing if it exceeds specification.
Place the rotor on the support so that the internal gear is facing
downward. Using puller tool 49-0813-240 (or equivalent) without its adaptor
ring, press the bearing out of the rotor. Being careful not to damage the
internal gear.
Place the rotor on the support with the internal gear facing upward. Place
the new rotor bearing on the rotor so that the bearing lug is in line with the
slot of the rotor bore.
Remove the screws which attach the adaptor ring to the special tool. Using
the special tool and adaptor ring, press fit the new bearing until the bearing
is flush with the rotor boss.
Oil Seal Inspection
Examine the oil seal while it is mounted in the rotor.
If the width of the oil seal lip is greater than 0.020 in. (0.5mm),
replace the oil seal.
If the protrusion of the oil seal is greater than 0.020 in. (0.5mm),
replace the seal.
Checking rotor oil seal width
Oil seal width and protrusion
Oil Seal Replacement
Pry the seal out by inserting a small prybar into the slots on the rotor.
Be careful not to deform the lip of the oil seal if it is to be reinstalled.
Fit both the oil seal springs into their respective grooves, so that their
ends are facing upward and their gaps are opposite each other on the rotor.
Insert a new O-ring into each of the oil seals. Before installing the
O-rings into the oil seals, fit each of the seals into its proper groove on
the rotor. Check to see that all of the seals move smoothly and freely.
Coat the oil seal groove and the oil seal with clean engine oil.
Gently press the oil seal into the groove with your fingers. Be careful
not to distort the seal. Be sure that the white mark is on the bottom side of
each seal when it is installed.
Repeat the installation procedure for the oil seals on both sides of each
rotor.
Apex Seals
Remove the carbon deposits from the apex seals and their springs. Do not
use emery cloth on the seals, as it will damage their finish.
Wash the seals and the springs in cleaning solution.
Check the apex seals for cracks.
Test the seal springs for weakness.
Apex seal height
Apex seal warpage
Apex seal-to-rotor clearance
Apex seal spring free height
Use a micrometer to check the seal height.
With a feeler gauge, check the side clearance between the apex seal and
the groove in the rotor. Insert the gauge until its tip contacts the bottom of
the groove. If the gap is greater than 0.0035 in. (0.09mm) for the 1983-85 12A
engine, or 0.0059 in. (0.15mm) for the 1984-90 13B engine, replace the seal.
The standard range for non-turbo engines is 0.0024-0.0040 in. (0.06-0.10mm)
and 0.0020-0.0040 in. (0.05-0.10mm) for turbo engines.
Check the gap between the apex seals and the side housing by using a
vernier caliper to measure the length of each apex seal. Compare this
measurement to the minimum figure obtained for the rotor housing width.
Check the apex seal spring for wear and measure its free height. If less
than 0.2165 in. (5.5mm), replace the spring.
If the seal is too long, sand the ends of the seal with emery cloth until
the proper length is reached. Do not use the emery cloth on the faces of the
seal.
Side Seals
Check the side seal free movement in the rotor groove. You should be able
to press down along its length with your finger.
Measure the side seal protrusion from the rotor surface. If the protrusion
is less than 0.02 in (0.5mm), replace the side seal spring.
Checking side seal-to-rotor groove
clearance
Checking side seal-to-corner seal
clearance
Measure the clearance between the side seal and its groove in the rotor
with a feeler gauge. (The standard clearance is given in the specification
chart, earlier in this section.) If the clearance is greater than 0.0039 in.
(0.10mm), replace the side seal.
Using a feeler gauge, check the clearance between the side seal and the
corner seal when the seals are installed on the rotor. If the clearance is
greater than 0.0157 in. (0.4mm), replace the side seal. When installing a new
side seal, correct the clearance between the side and corner seals by grinding
the end of the side seal and the rounded corner seal with a fine file. The
clearance should be 0.0020-0.0059 in. (0.05-0.15mm). If it exceeds this, the
performance of the seals will deteriorate.
There are 4 different types of side seals, depending upon
location. Do not mix up the seals and be sure to use the proper type of seal for
replacement.
Corner Seals
Inspect the corner seal and spring for wear, cracks, or damage and
replace, if necessary.
Make sure the corner seal has free movement by pressing on it with your
finger.
Corner seal protrusion
Measure the corner seal protrusion from the rotor surface. It should
protrude at least 0.02 in (0.5mm). If not, replace the corner seal spring.
Inspect the corner seal spring for wear.
Seal Springs
Check the seal springs for damage or weakness. Be especially
careful when checking the spring areas which contact either the rotor or the
seal.
Eccentric Shaft
Wash the eccentric shaft in solvent and blow the oil passages dry with
compressed air.
Check the shaft for wear, cracks, or other signs of damage. Make sure that
none of the oil passages are clogged.
Exploded view of eccentric shaft. Remove the oil jet
plug (indicated by the arrow) to check the spring and steel
ball
Checking eccentric shaft
run-out
Measure the shaft journals. Replace the shaft if any of its journals show
excessive wear.
Check eccentric shaft run-out. Rotate the shaft slowly and note the dial
indicator reading. Run-out should not exceed 0.0047 in. (0.12mm) as measured
from the end of the shaft. If run-out is greater than specification, replace
the eccentric shaft.
Check the blind plug at the end of the shaft. If it is loose or leaking,
remove it with an Allen wrench and replace the O-ring.
Check the operation of the needle roller bearing for smoothness by
inserting a mainshaft into the bearing and rotating it. Examine the bearing
for signs of wear or damage. Check the oil jet for spring weakness, sticking
or ball damage.
Replace the bearings, if necessary, with special bearing replacer tools
49-0823-073 and 49-0823-072, or equivalent.
Needle Bearing and Thrust Plate
Inspect the needle bearing for wear and damage.
Inspect the bearing housing and the thrust plate for wear and damage.
Oil Pump Drive Chain and Sprocket
Lay the chain on a flat surface and check the entire length for broken
links.
Check the oil pump drive and driven sprockets for missing and broken
teeth.
Replace parts as necessary.
Assembly of Internal Components
Replace all O-rings, rubber seals and gaskets with new parts. Place the
rotor on a rubber pad or cloth. Coat all the engine sliding surfaces with
clean engine oil.
Install the oil seal rings in their respective grooves in the rotors with
the edge of the spring in the stopper hole. The oil seal springs are painted
cream or blue in color. The cream colored springs must be installed on the
front faces of both rotors. The blue colored springs must be installed on the
rear faces of both rotors. When installing each oil seal spring, the painted,
square side of the spring must face upward toward the oil seal.
Oil seal spring installation
A used inner oil seal makes a good installation tool
for pressing in the new seal
Coat the new O-ring with clean engine oil and install in each seal groove.
Place each oil seal in the groove so that the square edge of the spring fits
in the stopper hole of the oil seal. Push on the head of the oil seal slowly
with your fingers, being careful that the seal is not deformed. Be sure that
the oil seal moves smoothly in the groove beforeinstalling the O-ring. An old
seal can be used as an installation tool.
Lubricate each oil seal and groove with engine oil. Check the movement of
the seal. It should move freely when the head of the seal is pressed.
Check the oil seal protrusion and install the seals on the other side of
each rotor. Oil seal protrusion must not exceed 0.016 in. (0.4mm).
Install the apex seals (without springs and side pieces) into their
respective grooves, so that each side piece will be positioned to the rear
side of the rotor.
Install the corner seal springs and corner seals into their respective
grooves.
Install the side seal springs and side seals into their respective
grooves.
Confirm the smooth movement of each seal by pressing its head.
When meshing the internal and stationary gears, make
sure at least one of the rotor apexes is positioned as
shown
Apply sealant to the front side of the front rotor
housing
Install the O-ring (right arrow), outer sealing rubber
(left arrow) and inner sealing rubber
Install the seal protector behind the inner sealing
rubber
Mount the front housing on a workstand so that the top of the housing is
up. Install the thrust plate so that the chamfered edge faces the front of the
housing. Torque the thrust plate bolts to 12-17 ft. lbs. (16-23 Nm).
Lubricate the internal gear of the rotor with engine oil.
Hold the apex seals with a rubber band around the rotor's perimeter to
keep the seals attached. Place the rotor on the front housing, being careful
not to drop the seals. Turn the front housing so that the sliding surface
faces upward.
Mesh the internal and stationary gears so that one of the rotor apexes is
at any one of the four places shown, then remove the rubber band which is
holding the apex seals in position.
Lubricate the front rotor journal of the eccentric shaft and the eccentric
shaft main journal with engine oil.
Insert the eccentric shaft. Be careful that you do not damage the rotor
bearing and main bearing.
Apply sealing agent to the front side of the front rotor housing.
Apply a light coat of petroleum jelly (not grease) onto new O-rings and
rubber seals, then install the O-rings and seals on the front side of the
rotor housing. If the engine is being overhauled, install the seal protector
behind the inner sealing rubber to improve durability.
The inner rubber seal is of the square type. The wider white
line of the rubber seal should face the combustion chamber and the seam of the
rubber seal should be positioned as illustrated. Do not stretch the rubber
seal.
Fitting an assist piece on the apex
seal
Install the side piece as shown under "O." (The spring
must butt against the apex seal lip.)
Rotary engine tension bolt tightening
sequence
Invert the front rotor housing, being careful not to let the rubber seals
and O-rings fall from their grooves, and mount it on the front housing.
Lubricate the tubular dowels with engine oil, then insert them through the
front rotor housing holes and into the front housing.
Insert each apex seal spring so that both ends of the spring may support
the back side of the seal.
Install the corner seal springs and corner seals into their respective
grooves.
Install the side seal springs and side seals into their respective
grooves.
Fit an assist piece between the spring and seal, then install each side
piece in its original position. Be sure that the spring seats properly on the
side piece, as shown.
Confirm the smooth movement of each seal by pressing its head.
Apply sealer to the rear side of the front rotor housing.
Install new O-rings, rubber seals and seal protector on the rear side of
the front rotor housing, in the same manner as on the front side.
Lubricate the side pieces with engine oil. Make sure that the front rotor
housing is free of foreign matter and lubricate the sliding surface of the
front housing with engine oil.
Turn the front housing assembly with the rotor, so that the top of the
housing is up. Pull the eccentric shaft about 1 in. (25mm).
Position the eccentric portion of the eccentric shaft diagonally, to the
upper right.
Install the intermediate housing over the eccentric shaft and onto the
front rotor housing. Turn the engine so that the rear of the engine is up.
Install the rear rotor and rear rotor housing, following the same steps as
for the front rotor and front rotor housing.
Lubricate the stationary gear and main bearing.
Install the rear housing onto the rear rotor housing. Make sure the side
pieces of the front and rear apex seals are not pinched between the rotor and
side housings.
If necessary, turn the rear rotor slightly to mesh the rear housing
stationary gear with the rear rotor internal gear.
Install a new washer on each tension bolt, and lubricate each bolt with
engine oil.
Install the tension bolts, then tighten them to specification using
several stages of the proper sequence. Be sure the bolts are installed in
their original positions with new seal washers. Longer bolts are used in later
engines and are not interchangeable.
On 1984-85 carbureted engines, bolt number 11 does not apply.
For those engines, delete bolt number 11 from the tension bolt torque
sequence.
After tightening the bolts, turn the eccentric shaft to be sure that the
shaft and rotors turn smoothly and easily.
Lubricate the oil seal in the rear housing.
On vehicles equipped with a manual transmission, install the flywheel on
the rear of the eccentric shaft so that the keyway of the flywheel fits the
key on the shaft.
Apply sealer to both sides of the flywheel lockwasher and install the
lockwasher.
Install the flywheel locknut. Hold the flywheel securely and tighten the
nut to 350 ft. lbs. (475 Nm).
On vehicles with an automatic transmission, install the key,
counterweight, lockwasher and nut. Tighten the nut to 350 ft. lbs. (475 Nm).
Install the driveplate on the counterweight and tighten the attaching nuts.
Turn the engine so that the front faces up.
Install the thrust plate with the tapered face down, and install the
needle bearing on the eccentric shaft. Lubricate with engine oil.
Install the bearing housing on the front housing. Tighten the bolts and
bend up the lockwasher tabs. The spacer should be installed so that the center
of the needle bearing comes to the center of the eccentric shaft, and the
spacer should be seated on the thrust plate.
Install the needle bearing on the shaft and lubricate it with engine oil.
Install the balancer and thrust washer on the eccentric shaft.
Install the oil pump drive chain over both of the sprockets. Install the
sprocket and chain assembly over the eccentric shaft and oil pump shaft
simultaneously. Install the key on the eccentric shaft. Be sure that both of
the sprockets are engaged with the chain before installing them over the
shafts.
Install the distributor drive gear onto the eccentric shaft with the
Fmark on the gear facing the front of the engine. Slide the spacer and
oil slinger onto the eccentric shaft.
Align the keyway and install the eccentric shaft pulley. Tighten the
pulley bolt to 72-87 ft. lbs. (98-118 Nm) on 1979-85 engines and 80-98 ft.
lbs. (108-133 Nm) on 1986-89 engines.
Turn the engine until the top of the engine faces up.
Check the eccentric shaft end-play in the following manner:
Attach a dial indicator to the flywheel. Move the flywheel forward and
backward.
Note the reading on the dial indicator, it should be 0.0016-0.0028 in.
(0.04-0.07mm).
If the end-play is not within specification, adjust it by replacing the
front spacer. Spacers come in four sizes, ranging from 0.3150-0.3181 in.
(8.00-8.08mm). If necessary, a spacer can be ground on a surface plate with
emery paper.
Check the end-play again and, if it is now within specification, proceed
with the next Step.
Remove the pulley from the front of the eccentric shaft. Tighten the oil
pump drive sprocket nut and bend the locktabs on the lockwasher.
Fit a new O-ring over the front cover oil passage.
Install the chain tensioner, if equipped, and tighten its securing bolts.
Position the front cover gasket and the front cover on the front housing,
then secure the front cover with its attachment bolts.
Install the eccentric shaft pulley again. Tighten its bolt to the required
torque value.
Turn the engine so that the bottom faces up.
Cut off the excess gasket on the front cover along the mounting surface of
the oil pan.
Install the oil strainer gasket and strainer on the front housing, then
tighten the attaching bolts.
Apply sealer to the joint surfaces of each housing.
Install the oil pan.
Turn the engine so that the top is up, then complete assembly of the
external components.
Assembly of External Components
CARBURETED ENGINES
Install the water pump.
Attach two O-rings to the oil filter body, then install the oil filter.
Rotate the eccentric shaft until the yellow mark (leading side mark)
aligns with the pointer on the front cover.
Align the marks on the drive gear and housing, then install the
distributor so that the lockbolt is in the center of the slot.
Rotate the distributor until the leading points start to separate (1979
only) or the air gap is correct (1980-1985), then tighten the distributor
locknut. (For more details, please refer to Section 2.)
Install the gaskets and thermal reactor/exhaust manifold.
Install the hot air duct.
Install the carburetor (if applicable) and intake manifold assembly.
Connect the oil tubes, vacuum tube and metering oil pump connecting rod to
the carburetor.
Install the decel valve, then connect the vacuum lines, air hoses and
wires.
Install the alternator bracket, alternator and retaining bolt, then check
the clearance. If the clearance is more than 0.006 in. (0.15mm), adjust the
clearance using a shim. Shims are available in three sizes: 0.0059 in.
(0.15mm), 0.012 in. (0.30mm), and 0.02 in. (0.50mm).
Install and properly tension the alternator and accessory drive belts.
Remove the engine from the stand and install it in the vehicle.
FUEL INJECTED ENGINES
Install the water pump and tighten the nuts in a crisscross sequence.
Tighten to 13-20 ft. lbs. (18-27 Nm). Be sure to use shims on the side housing
contact surfaces.
If shims are not used, the coolant will leak.
Apply engine oil to the new O-ring, then install the metering oil pump to
the front housing.
Place the exhaust manifold gasket in position and install the exhaust
manifold. Tighten to 23-34 ft. lbs. (31-46 Nm).
Install the hot air duct and absorber plate.
Install the intake manifold auxiliary ports. Installation should be made
so that the bigger sides of the auxiliary port valve shaft align with the
matching mark on the gasket, as illustrated.
Install the O-rings and the intake manifold and gasket.
Connect the metering oil pump pipes, and tighten to 14-19 ft. lbs. (19-26
Nm).
Install the fuel injection nozzles.
Install the delivery pipe assembly, the throttle/dynamic chamber, and the
emission device assembly as one piece. Tighten the delivery pipe body to 14-19
ft. lbs. (19-26 Nm), and the emission device assembly to 14-19 ft. lbs. (19-26
Nm).
Install the vacuum sensing tube, the air pump, and the engine hanger
bracket.
Align the leading timing mark (painted yellow) on the eccentric shaft
pulley with the indicator pin on the front cover.
On models equipped with a distributor, align the tally marks on the
distributor housing and driven gear. Install the distributor and locknut. Turn
the distributor housing until the projection of the signal rotor aligns with
the core of the leading side pick-up coil. Tighten the locknut. Install the
distributor rotor and cap.
On models equipped with a crank angle sensor, apply engine oil to a new
O-ring and install it on the crank angle sensor. Apply engine oil to the drive
gear, then match the mating mark and install the crank angle sensor on the
front housing.
Attach two O-rings to the oil filter body, then install the oil filter.
Install and properly tension the alternator and accessory drive belts.
Remove the engine from the stand and install it in the vehicle.