Engine mechanism - Camshaft
(4) Ensure whether the timing sprocket of VVT driver
will turn toward timing advance direction in de-
creasing the pressure of timing delay oil duct.
(5) When camshaft timing sprocket turns at max.
timing advance position, release the air pressure
in timing delay side oil duct, and then release the
air in timing advance side oil duct.
Hint: camshaft timing sprocket will turn only af-
ter the lock pin is released.
(d) Check the fixing state of max. delay position.
Ensure camshaft timing sprocket assembly is fixed at
max. delay position.
- Remove VVT driver assembly.
(a) Clip the camshaft with a jaw vice, and ensure VVT driver
is locked tightly.
Warning: be careful not to damage camshaft.
(b) As shown in the diagram, seal 5 oil ducts of camshaft
journal with vinyl rubber cloth.
Hint: there are 2 advance side oil ducts in the
groove of camshaft, and clog one of them
with rubber block.
(c) In opposite side of the groove, respectively prick a hole
on vinyl rubber cloth of advance side oil duct surface
and delay side oil duct surface.
(d) Send in 2 oil ducts (advance side oil duct and delay
side oil duct) with the surface rubber cloth pricked
under the pressure of 150Kpa.
Warning: cover the oil ducts with cloth to avoid
oil injecting out in pushing.
(e) Ensure whether the timing sprocket of VVT driver will
turn toward timing advance direction in decreasing the
pressure of timing delay oil duct.
Hint: camshaft timing sprocket will turn toward
advance direction only after the lock pin is
released.
(f) When camshaft timing sprocket turns at max. timing
advance position, release the air pressure in timing
delay side oil duct, and then release the air in timing
advance side oil duct.
Warning: if the air pressure in timing advance side oil duct is released earlier than that
in timing delay side oil duct, VVT driver assembly will move suddenly toward
delay side, and the lock pin will be damaged.
(c) Check rotating is smooth.
Besides max. delay position, turn VVT driver assembly within rotating rang and check rotating is
smooth.
Warning: Perform inspection with hands but not with
compressed air.
55
Delay side
oil duct
Advance
side oil
duct
Close
Open
Close
Open
Vinyl rubber cloth Rubber block
Delay side
oil duct
Advance
side oil
duct
Dropping
pressure
Maintaining
pressure
Delay side
oil duct
Advance
side oil
duct
Dropping
pressure
Maintaining
pressure
Delay side
oil duct
Advance
side oil
duct