77
PANEL REPAIRS
28
SEALING AND CORROSION PROTECTION
WATER LEAKS
Sealing charts in this section show those areas of the
bodyshell most likely to be affected by accident
damage and water leaks, and which could therefore
require re-treatment in repair. They do not show those
joint areas which only apply to factory assembly
operations and which are unlikely to be disturbed in
service (e.g. centre tunnel), or where the damage
would be so severe that the entire bodyshell would
normally be written off.
When water leakage occurs, always adopt a logical
approach to the problem using a combination of skill,
experience and intuition. Do not attempt to reach a
conclusion based only on visual evidence, such as
assuming that a leak emanates from the windscreen
because the footwell is wet. It will often be found that
the source of the leak is elsewhere. The correct
procedure will increase the chance of locating a leak,
however obscure it may seem.
Tools and Equipment
The following tools and equipment are recommended
for detection and rectification of water leaks:
1. Garden sprayer (hand-operated).
2. Wet/dry vacuum cleaner.
3. Dry absorbent cloths.
4. Battery torch.
5. Small mirror.
6. Weatherstrip locating tool.
7. Trim panel remover.
8. Small wooden or plastic wedges.
9. Dry compressed air supply.
10. Hot air blower.
11. Sealer applicators.
12. Ultrasonic leak detector.
During leak detection, the vehicle should be
considered in three basic sections:
•
The front interior space,
•
The rear passenger space (where
applicable), and
•
The rear loadspace or boot.
Testing
From the information supplied by the customer it
should be possible for the bodyshop operator to locate
the starting point from which the leak may be
detected. After the area of the leak has been
identified, find the actual point of entry into the vehicle.
A simple and effective means initially is an ordinary
garden spray with provision for pressure and jet
adjustment. This will allow water to be directed in a jet
or turned into a fine spray. Use a mirror and a
battery-powered torch (NOT a mains voltage
inspection lamp) to see into dark corners.
The sequence of testing is particularly important. Start
at the lowest point and work slowly upwards, to avoid
testing in one area while masking the leak in another.
For example, if testing started at the level of the
windscreen, any water cascading into the plenum
chamber could leak through a bulkhead grommet and
into the footwells. Even at this point it could still be
wrongly assumed that the windscreen seal was at
fault.
Another important part of identifying a water leak is by
visual examination of door aperture seals, grommets
and weatherstrips for damage, deterioration or
misalignment, together with the fit of the door itself
against the seals.
Sealing
When the point of the leak has been detected,
proceed to rectify it using the following procedure:
1. Renew all door aperture seals and weatherstrips
which have suffered damage, misalignment or
deterioration.
2. Check all body seals to ensure that they are
correctly located on their mounting flanges/faces
using a locating tool if necessary.
3. Dry out body seams to be treated using
compressed air and/or a hot air blower as
necessary.
4. Apply sealant on the outside of the joint
wherever possible to ensure the exclusion of
water.
5. When rectifying leaks between a screen glass
and its weatherstrip (or in the case of direct
glazing, between the glass and bodywork), avoid
removing the glass if possible. Apply the
approved material either at the glass to
weatherstrip or glass to body.