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1.2L REVOTRON ENGINE
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1. Check the height of each valve seat insert
with respect to the cylinder head mating
surface. Replace the valve seat if worn
beyond the specified limit.
2. Measure the runout of the valve seat with
respect to the valve guide axis. Maximum
runout is 0.030 mm. Replace or resurface the
valve seat(s) as necessary.
Cylinder Head Vale Seat Resurfacing
NOTE
The valve seat must be free from chatter
marks, scratches and other specifications.
1. Lap the valves and valve seats to a smooth
and even finish using lapping paste and a
hand pump grinder or by inserting the valve
into the cylinder head and rotating to achieve
the proper finish.
2. Coat the valve seat with carbon blue
I
Prussian blue dye and insert the appropriate
valve into the cylinder head.
3. Rotate the valve under axial pressure several
times and remove from the cylinder head.
4. Inspect the area of contact created by the
axial rotation of the valve.
The contact pattern should be equal and
unbroken around the circumference of the
seat.
The distance from the narrow diameter of
the valve seat face to the contact line
should be 0.5 mm.
F. Roller Finger Follower
1. Measure the diameter along several points of
both rocker arm roller. The rocker arm roller
diameter should be Ø17.0 -0.016/-0.027 mm.
Replace the rocker arm if deformed.
G. Hydraulic Lash Adjuster (HLA)
Hydraulic lash adjuster uses Engine oil pressure
for its operation. In case of a freshly assembled
Engine, do not run for a long time; there are
chances of valve train noise / tappet noise
appearing when the engine is started.
HLA noise can be heard as repeated tappet like
noise when engine is running at low idle speed.
Following procedure is recommended to eliminate
the noise.
Raise the Engine speed to 500rpm without
load
(Vehicle stationary)
to bleed the
hydraulic chamber of HLA. The noise should
disappear in15-30seconds.
If the noise still persists, run the engine
further under same condition (no load at 500
RPM) for several minutes. The noise should
disappear in 3 to 30 mins, in few cases.
In a very rare case if the noise is still heard,
the HLA is stuck in compressed position and
has to be replaced
Oil pressure in HLA gallery to be 0.7 bar for
normal functioning.