Discovery (1995+): Body Repair Manual

PANEL REPAIRS

PROCEDURES

WELDING PRECAUTIONS, ALUMINIUM PANELS

The body consists of a steel frame to which alloy outer
panels are attached. The front wings [fenders],door
panels and body side outer panels are made from a
special light magnesium-aluminium alloy.

These aluminium panels can be effectively repaired
using the ’Argon Arc’ process of welding. This is a
specialist operation which should only be carried out
by specialist body shop, or an operator skilled in
welding aluminium.

Under certain conditions it may not be practical to
repair an exterior damaged panel. In such
circumstances replacements for all exterior panels,
except for the roof, can be fitted.

Impacts which do not deploy airbags

CAUTION: Check for structural damage in
the area of the impact, paying particular
attention to bumper armature,

longitudinals, crash cans and bracketry.

Panel beating

1. Aluminium alloy panels can be beaten out after

accidental damage in the same way as sheet
steel. However, under protracted hammering the
material will harden and must then be annealed
to prevent the possibility of cracking. Do this by
heating the damaged area and allowing it to cool
gradually.

CAUTION: Due to the low melting point of
the material, take care to apply heat only
gradually.

CAUTION: Before applying heat to any
panel ensure that the panel is clean and
free from underseal and that the area to be

worked on is well clear of any combustible
materials. Ensure that all necessary precautions
are taken against fire.

Welding

General

CAUTION: Disconnect the battery negative
lead before welding operations start.

WARNING: When welding near the fuel
tank, drain the fuel system and remove the
tank removed before welding operations

start.

2. Clean off all grease and paint, and dry

thoroughly. Clean the area to be repaired,
including the edges, and extend this to at least
15mm (1 5/8 in) either side of the weld using a
stiff wire scratch brush or steel wool for this
purpose. In addition, clean the welding rod or
strip using steel wool. It is essential to observe
cleanliness in order to achieve a satisfactory
repair.

3. Use only 5 per cent magnesium aluminium

welding rod (5Mg/A), when carrying out repairs
to the aluminium body panels.

Welding tears and patches

1. When repairing a split or crack which extends to

the edge of a panel, drill a small hole at the end
furthest from the panel edge to prevent the
damage from spreading. When welding, start the
weld at the same point and work towards the
panel edge.

2. When welding a long split or crack, or making a

long welded joint, tack the edges to be welded at
intervals of between 50 and 100mm (2 to 4 in)
with spots. Do this by melting the metal at the
starting point of the weld and fusing it into a
small amount of the filler rod, repeating the
process at the suggested intervals. After this,
weld continuously along the joint increasing the
speed of the weld as the material heats up.

3. When applying a patch to a hole, cut and trim

the patch to the correct shape to fit the hole but
leaving a gap of 0.8mm (1/32 in) between the
patch and the panel. Proceed to weld as above.

CAUTION: Never apply an overlay patch.

Discovery (1995+): Body Repair Manual - part 39