Chevrolet CAMARO 1979 Service Manual page 144

2A.2 FRAME AND BODY MOUNTS
O N - C A R S E R V I C E
FRAME INSPECTION
l. Râise vehicle on â hoist (preferably â twin-post type).
2. Check for floor pan deterioration.
3. Check for loose dirt and rust around the inside of
the frame rails. on top ând al lhe ends where corrosion mây
exist h hidden areas. Check especially in the frame box
sections for accumulation of debris and remove if present.
UNOERBODY INSPECTION
L Râise vehicle on a hoist (preferably â twin-posl type).
2. Check for obvious floor pân deterioration.
3. Check for loose dirt and rust around the inside of
the floor pan reinforcement membe. access holes. This is
the firct indication that corrosion mây exist in hidden areas,
and that repairs may be r€quired before the finâl cl€âning
and protective treâtment is performed.
4. Using â chisel, ensur€ lhat the drâin pro!isions in
the floor pan reinforcement memb€Is are open. There are
drain holes in the body side panels also. These hol€s cân be
opened by using a punch or drift. The sidepanel drâin holes
arc in the rear section ofthe rocker panels, and in the lower
rear quarter pânels,
FRAME REPAIR
Vehicles involv€d in ân accident of any nature which
might resùlt ir a "bent' or 'sprung' frâme should always
be checked for proper frame alignment in addition to
steering g€ometry and wheel alignment. Figure 2A-2
illustrates typical points for taking diagonâl measurement
for checking the squâreness of the frame. The reference
points indicated are to be check€d with a tram gage. The
dimensions between the various reference points will show
wher€
strâightening operaaions arc
necessâry.
Corresponding m€âsurements must be eqùal within l/4
lnch.
l. Meaure X-X. To determine if frame hom or front
suspension crossmember is misaligned.
2. Measure Y-Y. To determine if center portion of
frame is misaligned.
3. }!{e^sùe z-2. To determine if rear end of frame is
rdisaligned.
Tramming Sequencê
when checking a ftâme for alignment in câse of
damage, the first step is horizontâl 'X' checking with a
tram gâge âs indicat€d above. Frame âiignment ch€cks on
âll models should be made with th€ tram gage points set at
the center of eâch locating point indicated and the cross bar
level to insure accurâcy,
IfatÉm gage is not avâilâble, the
''plumbbob" m€thod
of checking may b€ used. To assur€ âny degree of accuracy
when using this method, the vehicle should be on a level
floor.
By using this method, it is only necessary to have a
piece of cord âttached to an ordinâry surveyo/s plumb bob.
When measuring the distânce between two points, the ftee
end of the cord should be plâced on the retèrence point
allowing the plumb bob to hang to the floor. A check mârk
should be made on the floorjust under the tip of the plumb
bob. This operation should then be repeat€d at all reference
points. With these points located on the floor, they may
easily be measured with â rule.
The second step is checking the vertical dimensions
from the datum plane to the points to be trammed. With
the proper settings, the tmm bar will be on a plâne parallel
to thât of the frame. The exception to this would be *hen
one ofthe reference locâtions is included in the misaligned
area;then thepârallel plan€ between the frâme and the tram
bar may not prevâil. After completion ofrepâirs, train gage
should be set at specified dimension to check accurâcy of
F i g . 2 A 2 I y p i c a l F f a m e A l i g n m e n t C h e c k s