Dodge D150 1990 Service Manual page 669

1 1 - 1 2 EXHAUST SYSTEM AND INTAKE MANIFOLD •
EXHAUST MANIFOLD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Raise a n d support the vehicle.
(3) Remove t h e bolts a n d n u t s attaching t h e ex-
h a u s t pipe t o the exhaust manifold.
(4) Lower t h e vehicle.
(5) Remove bolts, n u t s and washers attaching m a n -
ifold to cylinder head.
(6) Remove m a n i f o l d from t h e cylinder head.
CLEANING AND INSPECTION
Clean m a t i n g surfaces on cylinder head and m a n i -
fold. Wash w i t h solvent a n d blow d r y w i t h com-
pressed air.
Inspect m a n i f o l d for cracks.
Inspect m a t i n g surfaces of manifold for flatness
w i t h a s t r a i g h t edge. Gasket surfaces m u s t be f l a t
w i t h i n 0.2 m m per 300 m m (0.008 inch per foot).
O n t h e R i g h t H a n d manifold, test manifold heat
control valve for free operation. I f necessary, apply a
suitable m a n i f o l d heat control valve solvent to b o t h
ends of t h e valve shaft. Be sure t h e manifold is
C O O L and solvent is allowed to soak a few m i n u t e s
to dissolve deposits. Then, w o r k valve back and f o r t h
u n t i l i t t u r n s freely. Be sure studs are f u l l y seated.
INSTALLATION
CAUTION: If the studs came out with the nuts
when removing the exhaust manifold, install new
studs. Apply sealer on the coarse thread ends. Wa-
ter leaks may develop at the studs if this precaution
is not taken.
(1) Position the exhaust manifolds on the two studs
located on t h e cylinder head. I n s t a l l conical washers
and nuts on these studs (Fig. 14 and 15).
(2) I n s t a l l two bolts and conical washers a t the i n -
ner ends o f the exhaust manifold outboard arms. I n -
s t a l l two bolts W I T H O U T washers on the center a r m
of exhaust manifold (Figs. 14 and 15). S t a r t i n g a t t h e
center a r m and w o r k i n g outward, t i g h t e n the bolts t o
27 N * m (20 f t . lbs.) torque and the stud nuts to 20
N T H (15 f t . lbs.) torque.
(3) Raise a n d support the vehicle.
(4) Assemble t h e exhaust pipe t o t h e exhaust m a n -
ifold a n d secure w i t h bolts, n u t s a n d washers.
T i g h t e n these n u t s to 33 N » m (24 ft. lbs.) torque.
(5) Lower t h e vehicle.
(6) Connect t h e battery negative cable.
8911-15
Fig. 14 Exhaust Manifold installation (Right Manifold
Shown)—3.9L
CONICAL WASHERS^
SQ^
Fig. 15 Exhaust Manifold Installation (5.2L Engine
Shown)