Hummer H1 Service Manual page 601

9-64 Axles, Suspension, and Frame
FRAME INSPECTION
General Information
The frame rails are constructed by arc-welding two "C" chan-
nels of preformed steel together to form a box cross section.
The frame rails are internally reinforced at bolt hole locations
by bushings or full cross-section spacers to prevent channels
from collapsing from attaching load. The frame is made by
bolting two non-identical frame rails to crossmembers. Cross-
members are held to stringent dimensional tolerances and
therefore must be replaced if damaged.
TRANSVERSE
CRACK
TWISTED RAIL
LONGITUDINAL CRACK
MANUFACTURING WELD
COMPLETE
TRANSVERSE
CRACK
Figure 9-151: Frame Damage
_________________________________________
INSPECTION
The visual inspection is the first and most critical step in form-
ing a decision of whether to repair or replace a damaged frame
component (Figure 9-151). Factors to consider when making a
visual inspection are:
1. Twisted frame rails are not repairable and must be
replaced.
2. Transverse tears or breaks extending across or into both
upper or lower corners are not repairable by welding.
3. Short longitudinal cracks up to 6 inches (15.2 cm) or split
welds can be repaired by heli-arc welding.
REINFORCEMENT
(NO LESS THAN 6-IN.
(15.2 CM) IN LENGTH)
REINFORCEMENT
LAP WELD
FRAME RAILS
BUCKLE
®