Great Wall GW491QE, Руководство по обслуживанию

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EM.2-8
(d)Selection฀of฀new฀valve฀guide
If฀the฀diameter฀of฀installation฀hole฀for฀valve฀guide฀on฀cylinder฀head฀is
greater฀than฀13.027mm,฀the฀installation฀hole฀needs฀a฀re-boring฀to฀ensure
the฀diameter฀is฀within฀(13.050 13.077)฀mm,฀and฀the฀external฀diameter
for฀0.05mm฀valve฀guide฀(an฀increased฀size฀for฀repair฀purpose)฀will฀be
applicable. the฀external฀diameter฀for฀standard฀valve฀guide฀shall฀be฀within
(13.045 13.060mm .
(e)Using฀copper฀rod฀and฀hand฀hammer,฀the฀valve฀guide฀shall฀be฀struck฀to
a฀degree฀that฀the฀opening฀snap฀ring฀is฀able฀to฀contact฀cylinder฀head.
(f)To฀make฀the฀clearance฀between฀valve฀guide฀and฀new฀valve฀rod฀meet
relevant฀standard฀&requirement,฀a 8mm฀sharp฀reamer฀shall฀be฀used฀to
ream฀the฀inner฀diameter฀of฀valve฀guide.
Standard฀clearance:
Air฀inlet฀valve฀฀(0.025 0.060)mm
Air ฀exhaust฀valve฀฀(0.030 0.065)mm
11.฀Check฀and฀abrade฀the฀valve
(a)An฀abrading฀method฀will฀be฀applied฀to฀clear฀away฀any฀indent
or฀carbon฀deposit฀from฀the฀valve.
(b)Check฀ whether฀ the฀ cone฀ angle฀ on฀ valve฀ surface฀ has฀ been
abraded฀to฀a฀correct฀angle.
Cone฀angle฀on฀valve฀surface 44.5
Note:฀The฀abraded฀amount฀shall฀be฀decreased฀to฀a฀Min.
degreewhen฀possible฀yet฀sufficient฀to฀remove฀any฀damage
remainedon฀the฀surface.
(c)Inspection฀on฀edge฀thickness฀for฀valve
Min.฀edge฀thickness฀specified฀as฀below
A ir ฀inlet฀valve฀0.5mm
Air ฀exhaust฀valve฀฀0.8mm
The฀valve฀shall฀be฀changed฀whereby฀edge฀thickness฀on฀the฀head฀of฀valve
is฀less฀than฀Min.฀value.
(d)Inspection฀on฀the฀whole฀length฀of฀valve
Standard฀whole฀length฀of฀valve฀ mm
The฀valve฀shall฀be฀changed฀whereby฀the฀whole฀length฀of฀valve฀is฀less฀than
Min.฀value.
edge฀thickness
whole฀length
Standard whole length
of valve
M in. length
E ngine
model A ir inlet
valve
A ir exhaust
valve
A ir
inlet
valve
A ir inlet
valve
Cleanup฀/inspection฀on฀each฀spare฀part
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