Frame Straightening - Jeep J-10 Series 1982 Technical & Service Manual

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FRAME ALI6NMENT
The most efficient method of checking frame align
ment is with a frame alignment machine.
NOTE: The following procedure is adequate for check
ing most frame dimensions. However, if torsional twist
or frame rail height is in question, the vehicle must be
checked on an alignment machine using datum gauges.
Follow alignment machine manufacturers instructions.
If a frame straightening machine is not available,
frame alignment may be determined by using the "X" or
diagonal method. Figures 3F-1 through 3F-5 provide all
frame dimensions.
The most convenient method of checking frame di
mensions is to locate with a plumb-bob and chalk mark
on a level floor all dimensional points from which meas
urements are taken. This is known as "plumb-bobbing"
the frame. If working on a cement floor, clean it so that
the chalk marks will be visible underneath the frame. If
working on a wooden floor, lay sheets of paper under
neath the vehicle. Drop a plumb-bob from each point
indicated in figures 3F-1 through 3F-5, marking the
floor directly underneath the point. Satisfactory check
ing depends on the accuracy of the marks in relation to
the frame.
To check points that have been marked, carefully
move the vehicle away from the layout on the floor, and
proceed as follows:
Check the frame at front and rear end using corre
sponding marks on the floor. If widths correspond to
frame specifications, draw a centerline the full length of
Page
Doors 3F-7
Btseral 3F-7
GENERAL
Assembled sections or any of the individual panels
available for replacement are complete and may be in
stalled as a unit. When only a portion of the unit is
damaged, the damaged unit may be cut from the body at
the location best suited for welding, and the new unit cut
to the desired size and welded in place.
Galvanized Panels
For protection against corrosion, vulnerable panels on
all models are galvanized. A conversion coating must be
applied to these panels prior to painting to ensure good
adhesion of the paint.
BODY AND FRAME COMPONENTS 3F-7
the vehicle, halfway between the marks indicating front
and rear widths. If frame width is not correct and the
centerline cannot be laid out from checking points at the
end of the frame, it can be drawn through intersections
of any two pairs of equal dimensions.
With the centerline correctly laid out, measure the
distance to several opposite points over the entire length
of the frame. If the frame is in proper alignment, oppo
site measurement should be the same.
To locate the points at which the frame is sprung,
measure the diagonals between selected points on the
frame (figs. 3F-1 through 3F-5).
If the diagonals in each pair are within 1/8 inch, that
part of the frame included between points of measure
ment may be considered as properly aligned. These diag
onals should also intersect at the centerline. If the
measurements do not agree within the above limits, it
means that a frame alignment correction is necessary
and will have to be made between those points that are
not equal.
NOTE: During the process ofstraightening theframe,
be extremely careful not to overstretch the frame. This
could cause the already aligned sections of theframe to
become misaligned or weakened.
FRAME STRAIGHTENING
A bent or twisted frame may be straightened, pro
vided the extent of misalignment is not excessive. Se
verely damaged frame parts should be replaced.
PANELS
Pigs
Rear Quarter Panels 3F-8
Replacement
Where replacement is required, careful examination
should be made as to the extent of damage to determine
which panels require replacement.
In most cases, the weld joints of one panel to another
are visible and can be separated for installation of a new
panel.
DOORS
The complete door, with outer and inner door panels
flanged and welded together and primed, is available as
well as the outer panel only.
These outer panels may be used in cases in which the
inner panel and pillar assemblies are not damaged to
avoid the extra expense of using a complete door.