Chevrolet 10 Series 1970 Service Manual page 140

FRAME 2-2
H orizontal Check
1. M easure fram e width at front and re a r.
correspond to sp ecification s, draw centerline full
length o f veh icle halfway between lines indicating
front and re a r widths. If fram e widths are not c o r ­
rec t, layout cen terlin e as shown in Step 4.
2. M easure distance fro m cen terlin e to corresponding
points on each side o f fram e layout over entire
length. Opposite side
respond within 3/16".
3. M easure diagonals m arked
lengths o f in tersectin g diagonals are equal and these
diagonals in tersect the cen terlin e, fram e area in­
cluded between these points o f m easurem ent may be
considered in alignm ent.
4. If front or re a r end o f fram e is damaged and width
is no lon ger within lim its , fram e centerline may be
drawn through the in tersection o f any two previou sly
drawn p a irs o f equal, in tersectin g diagonals.
Vertical Check
V e rtic a l dim ensions are checked with a tram m ing bar
fro m indicated points on the fram e (figs. 4-8).
am ple, i f the tram bar is set at point B with a v e r tic a l
poin ter length o f 8-1/4 inches, and at point E with a
F ig . 3 —Frame H o riz o n ta l C h e c k in g —T y p ic a l
If widths
m easurem ents should c o r ­
A , B and If the
C .
F or ex­
v e rtic a l pointer length o f
ence o f 3 inches), the tram bar should be p a ra lle l with
the fra m e. If the area is twisted or m isaligned in any
way, tram bar w ill not be p a ra lle l.
bar v e rtic a l pointers on opposite sides o f the fram e side
r a il is p refera b le in that fra m e tw ist w ill show up during
this v e rtic a l check. F igu res
points, with dim ensions fo r variou s fra m es shown in the
chart below.
Frame Repair
W elding
B efore w elding up a crack in fra m e, a hole should be
d r ille d at the starting
spreading. Widen and V groove crack to allow com plete
w eld penetration.
NOTE: Do not weld into corn ers o f fram e or
along edges o f side ra il flanges.
these points w ill tend to weaken the fra m e and
encourage new cracks.
Bolting
W h erever riv e ts or failed bolts a re replaced, bolt hole
must be as near the O.D. o f the bolt as possible to p r e ­
vent bolt from working and w earing. D r ill out and line
ream hole (o r holes) to the bolt O.D.
inches (a height d iffe r ­
5 - 1 / 4
P la cin g the tram
show typical checking
4 - 8
point o f the crack to prevent
W elding at
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