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EM-36
ENGINE MECHAN ICAL
-
Compression Check
'1
2 H -
T l
C O M P R E S S I O N C H E C K [ 1 2 H -TJ
NOTE: If
there is lack of power, excessive oil consump
tion or poor fuel economy, measure the cylinder compres
sion pressure.
1 . WARM UP AND STOP E N G I N E
2.
REMOVE I N J ECTION N O Z Z L E S IS
• •
p a g e F U -91
3.
CHECK C Y L I N D E R C O M P R E S S I O N PRESSURE
(s)
Inslsll
SST
(gauge adapler)
10 Ihe
injec tion n o z z l e
h o l e .
S S T
0 9 9 9 2 - 0 0 0 2 3
Ibl Connect
S S T
(compression gauge)
10
S S T
(gauge
adapter!.
SST 0 9 9 9 2 - 0 0 0 2 3
kl Fully open t h e t h raille valve.
Idl
W
h
i
l
e
crank.ing the engine with t h e starter, measure
t h e com pression pressure.
NOTE:
Always use a fully charged battery to obtain
engine revolutions o f more than 2 5 0 rpm.
Ie) Repeal steps
Is)
through (dl for each cylinder.
Compression pressur e :
3 0 . 0 kg/cm1 (427 p s i . 2.942 k Pa) or more
Minimum pressure:
20.0 k g/cm2
(284
psi, 1 ,9 6 1 kPal
Difference between each cylinder:
2,0 kg/cm� (28 psi, 1 96 k Pal or less
(fl
I f
the cylinder compression i n one or more cylinders
is low, pour
a
small amoun t of engine oil i n l o the
cylinder through the injection nozzle hole a n d repeat
sleps (a) thro u g h (d)
for
t h e cylinder with low com
pression,
•
If
adding oil helps t h e com pression, chances are
that the piston rings a nd/or cyli nder bore are worn
or damaged .
•
If pressure stays low. a valve may be Slicking or
seating impro perly, or t here may be leakage past
t h e gasket.
4.
INSTALL I N J ECTION NOZZLES
(See steps 1
to
6 o n pages
F
U - 1 4 and 1 5)