Mitsubishi S4E User Manual

CONSTRUCTION AND FUNCTION
Crankcase
-- 1
a
4
l-Cran kCiU. e 3· Side $.,1
2 · ~ II nde r $Ieeve 4 ~ ~iI' i ng CillJS
Cr ankcase and cyl in der block
Cmnkcase
The crankcm and cylinder block ar e in one, shaped as
a sin gJ e cas lmg. into which Ih e c yl inde r sl ee ves made of
16
a spe c ial c ast iron are press -fitted. The sleev es are of
" dry" type: th ey are . not in d ir ect cOntact with engine
c.oolant .
The cTank"", as , whole is designed f OT high rigidily;
th e strength b uilt into it is. calcu l ated to withstand
l
wi th
an a mpl e m ar g in , the s oevere cydic~ t ress. of complex
nature imparted by the i nterna l runn i ng part s.
These st resses ~ry from on e part of the c ran kc ase to
another as jn an y di e sel engine; lhe needed r igi di ty and
durability are sec ll re d by th e ski n section. w hich is stu d
mo re s ubs tanti aJ and exten ding far below the leve l at
which con ventiona l· desisn crankca. s.€ s ar e te r mLI )ue d [ 0
mote with th e o il p an .
Eoch main bealing ca p is filted inlo and held by the
cran kcase, thu s proyjding a mo re re liabl e su ppor t for the
crankshaft at fiv e pl.ces along ils length.
Main, thrust and big- <md bearings
The fi ve mai n bearings are of sh ell type, each co nsisting
of I wo half she ll s, there being no distinclion between
lhe two: e ach may be l ocat ed on t op or bottO n) at the
l ime of hearing installa ti on in engine reassembly.
Crankshaft thrust is taken up al No. 5 journal. Three
bearing pJates
l
each in the form of half-ring) ate used:
t\Vo on the teat and one on the bottom f ront side of
No. 5 bearing. The", U ,rust plales are he ld in place by
spring p ins_
Connecting-rod bearings too or. of ,heU Iype, each shell
being
of tli-melal design . Tho sheU is essentially a kelmel
metal fused 10 a steel backing base .nd covered by an
over la y of a l ead -tin alloy deposi ted by plaling.
l ·Ma in bearing 2· T"hru st bear ing

Mitsubishi S4E Specifications

General

Brand	Mitsubishi
Model	S4E
Category	Engine
Language	English