Mitsubishi 4DQ50 - Model 40 Q50 Engine Service Standard

Model 4DQ 50 Eng n e
SeaiaT Units
!
Parts
1.AiI:
Checkup Items
ominal Sett ing Limi t of Repair'
Staniard
(Clearance) I
1
Max. speed
15-10qb higher than
Not
below rated I
I
rated speed
speed
1~
nOr above it
2 Min speed
70D-750r pm(Pneuma tic
Not above SOO
Govl~
650-700q:m(Weehand.;,~
r.p.m.
3
Engine preformance (on bench)
4
CoEnpression pressure
! Above 20q/cm
2
Not below
'(at 15D-200r.p.m. )
16kg/cm
2
~-4.IqVcm '\.at 1,oUO
Not oep:/W
5
Engine oi 1
pressure
r'r~~ ~~hi~er
2:~cm2
1.5 cm
Z
in ldl ino
O. em
z
General
I
...
..c:
CD
...
e
±3
6
Valve timing
-0
(crank angle)
~
""
...
...
'"
::I
-
;:;
7
Injection star~ing
~e~igh
±10(erank
tlmUlg
angle)
1
... II>
Bore
84"tP
+0.035-0
Cyl inder
8
+0.20
-
II> '"
out of round
-
~ess than 0.015
~
-0 ""
bore
.: ~
Taper
-
ess than 0.015
"-»
"- .:
n
- ""
Top
I
» ...
9
Strain
Less than 0.05
0.2
o <.>
surface
,
Projection of pistons +o.3!N-O.75
10
abO'ie cyl inder crank-
case top surface
Per iphery 111
Outer diam.
83.46P
-
-
!!
(0.2)
...
Top
2
+0.020-:0.040
""
0-
'"
Rings and
Width and
+0.015-0.035
(0.15)
c
12
2nC1
2
tIC
0
ring
standard
c
..
groO'les
clearance
oil
4
+0.015-0.035 (0.15)
I
'"
~
.-
S
P-
c
Piston pin
llUIer and outer diams
I
~
bosses and 13
and
standa1d
25tP
0.011T-O
(0.05)
piston pins
e earans
i
Weight
14
Wei~difference
±3gr
I
4 .g
,
PiStonS
I
- 80-