Water Ingress

Water Ingress

Background

If your Mondeo suffers from water in the boot, you might be able to identify the leak by checking the following areas:

Method

Rear light clusters

The seals tend to go on these with Mk2 Mondeos (and Mk1, to a lesser extent).

Simply replace or use silicone filler

Ford do not list the seals for the rear lights as a seperate item you will need to purchase new clusters at £80.00 each!

Air Vent

The air vent above the rear wheel arches - the membrane may have come away

Roof Trim

The roof trim rails where the roof rack fits - water can get in here and run down the C pillar

Passenger Footwell

A leaking passenger footwell is quite possibly caused by a leaking pollen (or cabin) filter. The gasket around the base of the holder attached to the bulkhead goes hard and lets water in. Also, if the cover isn't on the holder properly, or if the filter is incorrectly fitted then water will leak in...

Cable seal

On the saloon model, where the cables for the boot lid release and lights come out of the top of the boot the seal can leak letting water into the left of the boot.

Mk3

On a Mk3 Mondeo, water ingress can also be caused by the foam insulating panel (between the interior door panel and the actual door itself) coming unstuck. There are two ways to fix this:

Using a hair dryer, try to reactivate the black sticky sealant, and reseal. Use a silicon sealant for automotive, not kitchen or bathroom use, (no-one will ever see it) and do the same. Using regular silicone will eventually give cause rust problems.

Submitted by Monkeyra, funkyg, vince_121, ST_Willie and FlashBastd

Note added:

You can diagnose this problem in the following way:

Open the doors in turn. Use your finger to open a gap between the window and the rubber seal at the bottom of the glass on the outside. Pour a pint of water down the hole. Have someone observe the underside of the door. The door is designed to let the water out through drain holes on the bottom. If any water is coming from between the bottom of the internal plastic trim and the painted metal surface of the door, then you have found your problem. It is due to the water-tight membrane behind the internal trim coming unstuck. This allowes the water to bead down onto the carpet. You would not notice until the carpet was very wet. I fixed mine with silicone but you can have the membranes replaced relatively cheeply.