Mitsubishi MOTORS Space Runner 1998, Workshop Manual

Page: 48 / 1164

ENGINE <4G6> -
On-vehicle Service
11A-14
MANIFOLD VACUUM CHECK
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Disconnect the ventilation hose from the positive
crankcase ventilation (PCV) valve, and then connect a
vacuum gauge to the ventilation hose.
3. Check the intake manifold vacuum while the engine is
idling.
Limit: Min. 56 kPa
LASH ADJUSTER CHECK
If an abnormal noise (knocking) that seems to be coming
from the lash adjuster is heard after starting the engine and
does not stop, carry out the following check.
NOTE
(1) The abnormal noise which is caused by a problem
with the lash adjusters is generated after the engine
is started, and will vary according to the engine speed.
However, this noise is not related to the actual engine
load.
Because of this, if the noise does not occur
immediately after the engine is started, if it does not
change in accordance with the engine speed, or if
it changes in accordance with the engine load, the
source of the noise is not the lash adjusters.
(2) If there is a problem with the lash adjusters, the noise
will almost never disappear, even if the engine has
been run at idle to let it warm up.
The only case where the noise might disappear is
if the oil in the engine has not been looked after
properly and oil sludge has caused the lash adjusters
to stick.
1. Start the engine.
2. Check that the noise occurs immediately after the engine
is started, and that the noise changes in accordance
with changes in the engine speed.
If the noise does not occur immediately after the engine
is started, or if it does not change in accordance with
the engine speed, the problem is not being caused by
the lash adjusters, so check for some other cause of
the problem. Moreover, if the noise does not change in
accordance with the engine speed, the cause of the
problem is probably not with the engine. (In these cases,
the lash adjusters are normal.)
3. While the engine is idling, check that the noise level does
not change when the engine load is varied (for example,
by shifting from N ® D).
If the noise level changes, the cause of the noise is
probably parts striking because of worn crankshaft
bearings or connecting rod bearings. (In such cases, the
lash adjusters are normal.)
Vacuum gauge
Plug