Pcv Valve Or Ccv Hose Check, Cleaning And Replacement - Jeep cherokee 1989 Owner's Manual

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COOLANT
TEMPERATURE
SENSOR
39.5 On four and inline six-cylinder engines, the block
drain plug is located on the driver's side of the engine
block, below the exhaust manifold; V 6 engines have t w o
block drain plugs at the lower rear of each side of the
engine block (inline six-cylinder engine shown)
3 Once the engine is completely cool, remove the radiator cap (four-
cylinder and V6 engines) or coolant pressure bottle cap (inline six-
cylinder engines).
4 Move a large container under the radiator drain to catch the coolant.
Attach a hose to the drain fitting to direct the coolant into the con-
tainer, then open the drain fitting (see illustrations) by turning it counter-
clockwise (a pair of pliers may be required to turn it).
5 After the coolant stops flowing out of the radiator, move the con-
tainer under the engine block drain plugls) (see illustration). Remove
the plug(s) and allow the coolant in the block to drain.
6 While the coolant is draining, check the condition of the radiator
hoses, heater hoses and clamps (refer to Section 9 if necessary).
7 Replace any damaged clamps or hoses.
8 Once the system is completely drained, flush the radiator with fresh
water from a garden hose until
it
cylinder engines, add the flush water through the coolant pressure bot-
tle. The flushing action of the water will remove sediments from the
radiator but will not remove rust and scale from the engine and cooling
tube surfaces.
9 These deposits can be removed with a chemical cleaner. Follow
the procedure outlined in the manufacturer's instructions. If the radiator
is severely corroded, damaged or leaking, it should be removed (Chap-
ter 3) and taken to a radiator repair shop.
1 0 Remove the overflow hose from the coolant recovery reservoir
(four-cylinder and V6 engines). Drain the reservoir and flush it with
clean water, then reconnect the hose.
11 Close and tighten the radiator drain. Install and tighten the block
drain plugs.
12 Place the heater temperature control in the maximum heat position.
13 On four-cylinder and V6 engines, slowly add new coolant (a 50150
mixture of water and antifreeze) to the radiator until it's full. Add coolant
t o the reservoir up t o the lower mark. On inline six-cylinder engines,
add coolant to the pressure bottle until the level is at the top of the
post (see Section 9).
1 4 Leave the radiator or pressure bottle cap off and run the engine
in a well-ventilated area until the thermostat opens (coolant will begin
flowing through the radiator and the upper radiator hose will become
hot).
15 Turn the engine off and let it cool. Add more coolant mixture to
bring the level back up to the lip on the radiator filler neck or top of
the post (inline six-cylinder engine).
16 Squeeze the upper radiator hose to expel air, then add more coolant
mixture if necessary. Replace the radiator cap.
17 Start the engine, allow it t o reach normal operating temperature
and check for leaks.
40 Positive Crankcase Ventilation (PCV) valve or Crankcase
Ventilation (CCV) hose check, cleaning and replacement
Refer to illustration 40. 11
Check
The PCV valve or CCV hose is located in the rocker arm cover.
The Motor Manual Guy
Chapter Tune-up and routine maintenance
DRAIN
PLUG
runs clear at the drain. On inline six-
2 With the engine idling at normal operating temperature, pull the
valve (with hose attached) or CCV hose from the rubber grommet in
the cover.
3 Place your finger over the valve or hose opening. If there's no
vacuum, check for a plugged hose, manifold port, or valve. Replace
any plugged or deteriorated hoses.
4 Turn off the engine and shake the PCV valve, listening for a rattle.
If the valve doesn't rattle, replace it with a new one.
PC V valve replacement
5 To replace the valve, pull it from the end of the hose, noting its
installed position and direction.
6 When purchasing a replacement PCV valve, make sure it's for your
particular vehicle and engine size. Compare the old valve with the new
one t o make sure they're the same.
7 Push the valve into the end of the hose until it's seated.
8 Inspect the rubber grommet for damage and replace it with a new
one if necessary.
9 Push the PCV valve and hose securely into position.
CC V hose and orifice cleaning
1 0 Later models are equipped with a CCV system which performs the
same function as the PCV system but uses a rubber fitting with a
molded-in orifice which is pressed into a hole in the rocker arm cover.
The fitting is connected to the intake manifold by a plastic hose.
1 1 If there is no vacuum at the end of the hose (Step
engine, remove the fitting and clean the hose with solvent, clean the
fitting orifice (see illustration) if it's plugged. If the fitting or hose are
cracked or deteriorated, replace them with new ones.
1 2 Install the fitting and hose securely in the rocker arm cover.
41 Evaporative emissions control system check
Refer to illustration 4 1.2
1 The function of the evaporative emissions control system is to draw
fuel vapors from the gas tank and fuel system, store them in a charcoal
canister and route them to the intake manifold during normal engine
operation.
2 The most common symptom of a fault in the evaporative emissions
system is a strong fuel odor in the engine compartment. If a fuel odor
is detected, inspect the charcoal canister, located in the engine com-
partment (see illustration). Check the canister and all hoses for damage
and deterioration.
3 The evaporative emissions control system is explained in more
detail in Chapter 6.
42 Exhaust Gas Recirculation (EGR) system check
Refer to illustration 42.2
1 The EGR valve is usually located on the intake manifold, adjacent
to the carburetor or TBI unit. Most of the time when a problem develops
in this emissions system, it's due t o a stuck or corroded EGR valve.
2 With the engine cold to prevent burns, push on the EGR valve dia-
phragm. Using moderate pressure, you should be able t o press the dia-
phragm in-and-out within the housing (see illustration).
3 If the diaphragm doesn't move or moves only with much effort,
replace the EGR valve with a new one. If in doubt about the condition
of the valve, compare the free movement of the valve with a new one.
4 Refer t o Chapter 6 for more information on the EGR system.
43 Spark plug replacement
Refer to illustrations 43.2, 43.5a, 43.5b, 43.6 and 43.10
1 Open the hood.
2 In most cases, the tools necessary for spark plug replacement in-
turn off the