Vertical Check; Frame Repair; Welding; Bolting - Chevrolet 10 1971 Series Chassis Service Manual

FRAME 2-2

Vertical Check

Vertical dimensions are checked with a tramming bar
from indicated points on the frame (figs. 3 and 4). For
example, if the tram bar is set at point B with a vertical
pointer length of 8-1/4 inches, and at point E with a
vertical pointer length of 5-1/4 inches (a height differ­
ence of 3 inches), the tram bar should be parallel with
the frame. If the area is twisted or misaligned in any
way, tram bar will not be parallel. Placing the tram
bar vertical pointers on opposite sides of the frame side
rail is preferable in that frame twist will show up during
this vertical check. Figures 3 and 4 show typical check­
ing points, with dimensions for various frames shown in
the chart below.
Fig. 2— Frame Horizontal Checking— Typical

Frame Repair

Welding

Before welding up a crack in frame, a hole should be
drilled at the starting point of the crack to prevent
spreading. Widen and V groove crack to allow complete
weld penetration.

Bolting

Wherever rivets or failed bolts are replaced, bolt hole
must be as near the O.D. of the bolt as possible to pre­
vent bolt from working and wearing. Drill out and line
ream hole (or holes) to the bolt O.D.
Do not weld into corners of frame or
NOTE:
along edges of side rail flanges. Welding at
these points will tend to weaken the frame and
encourage new cracks.
10-30 CHEVROLET TRUCK SERVICE MANUAL