Dodge ram truck 3500 1996 Service Manual page 1206

1 1 - 4 EXHAUST SYSTEM AND INTAKE MANIFOLD
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D I A G N O S I S AND T E S T I N G
EXHAUST SYSTEM DIAGNOSIS
CONDITION
POSSIBLE C A U S E
C O i i E C f l O N
EXCESSIVE EXHAUST NOISE
1. Leaks at pipe joints.
2. Burned or blown-out muffler.
3 . Burned or rusted-out exhaust pipe.
4 . Exhaust pipe leaking at manifold flange.
5 . Exhaust manifold cracked or broken.
6 . Leak between exhaust manifold and
cylinder head.
7 . Restriction in muffler or tail pipe.
1. Tighten clamps at leaking joints.
2. Replace muffler assembly. Check
exhaust system.
3. Replace exhaust pipe.
4 . Tighten connection attaching nuts.
5 . Replace exhaust manifold.
6 . Tighten exhaust manifold to cylinder
head stud nuts or bolts.
7. Remove restriction, if possible. Replace
muffler or tail pipe, as necessary.
LEAKING EXHAUST GASES 1. Leaks at pipe joints.
2. Damaged or improperly installed gaskets.
1. Tighten clamps at leaking joints.
2. Replace gaskets, as necessary.
ENGINE HARD TO WARM UP
OR WILL NOT RETURN TO
NORMAL IDLE
1. Blocked crossover passage in intake
manifold.
1. Remove restriction or replace intake
manifold.
J9211-3
INTAKE MANIFOLD DIAGNOSIS
An intake manifold leak is characterized by lower
than normal manifold vacuum. Also, one or more cyl­
inder may not be fuctioning.
WARNING: U S E EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT PUT YOUR
HANDS NEAR THE P U L L E Y S , B E L T S OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine allowing i t to warm up.
(2) Inspect for disconected vacuum hoses or hard­
ened or cracked vacuum lines.
(3) With a spray bottle, spray a small stream of
water on the suspect area.
(4) I f there is a change i n RPM'S, the suspected
leak has been found.
(5) Repair as required.
R » M A U B I N S T A L L A T I O N
EXHAUST PIPE
REMOVAL
(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove exhaust manifold bolts, retainers and
nuts (Fig. 3) (Fig. 4).
(4) Remove the clamp nuts (Fig. 3) (Fig. 5).
(5) Disconnect the exhaust pipe from the support
hangers on the 5.9L (Heavy Duty) and the 8.0L
engines (Fig. 4).
(6) Remove the exhaust pipe.
Fig. 3 Exhaust Pipe for 3.9L, 5.2L and 5.9L—Light
Duty
INSTALLATION
(1) Connect the exhaust pipe support hangers on
the 5.9L (Heavy Duty) and the 8.0L engine (Fig. 4).
(2) Position the exhaust pipe for proper clearance
with underbody parts.