Chevrolet BEAUVILLE SPORTVAN G10 SERIES, Руководство по обслуживанию

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FRAME
SECTION 2
GENERAL DESCRIPTION
The fram e side rails, cross sills and outriggers are part o f the
u n d erb o d y assem bly w hich is a w elded u n it o f th e body
assem bly (see S ection 1).
M isalignm ent o f th e u n d erb o d y can affect door opening fits
and also influence th e suspension system , causing suspension
m isalignm ent. It is essential, th e re fo re, th a t underbody align­
m ent be exact to w ithin — 1 /1 6 ” o f th e specified dim ensions.
UND ER BO DY A L IG N M E N T
One m e th o d o f determ ining the alignm ent o f th e u n d e r­
b o d y is w ith a tram gauge w hich should be sufficiently flexible
to o b ta in all necessary m easurem ents up to three quarters the
length o f th e vehicle. A good tram m ing to o l is essential for
analyzing and determ ining th e e x te n t o f collision m isalignm ent
present in u n d erb o d y co nstruction.
M EASURING (Fig. 1)
To m easure the distance accurately betw een any tw o
reference points on th e u n d erb o d y , tw o specifications are
required.
1. The horizo n tal dim ension betw een th e tw o points to be
tram m ed.
2. The vertical dim ension from th e datu m line to the points
to be tram m ed.
The tram bar should be on a parallel to th a t o f th e body
plane. The excep tio n to this w ould be w hen one o f the
reference locations is included in th e misaligned area; th e n the
parallel plane betw een the body and th e tram bar may n o t
prevail. A fter com p letio n o f th e repairs, th e tram gauge should
be set a t th e specified dim ension to check th e accuracy o f th e
repair o peration.
EXCESSIVE BODY DAMAGE
I f damage is so extensive th a t key locations are n o t suitable
as reference p o in ts, repair o p erations should always begin w ith
the u n d erb o d y area. All o th e r com ponents should be aligned
progressively from th is area. Unlike th e conventional ty p e o f
fram e design, th e u n itize d ty p e o f body c o n stru c tio n seldom
develops th e tw o co nditions o f “ tw is t” and “ diam o n d ” in th e
underb o d y area as a result o f fro n t or rear end collisions,
th e re fo u , th e re usually is an undam aged area suitable as a
beginning reference point.
C H E V Y V A N S H O P M A N U A L