Door Related Water Leaks
It’s relatively common to find water that has leaked to the interior of the 2000+ Bonneville. It will generally accumulate in the front, rear or both floor areas. The focus of this article is to help detect leaks from a door or weather strip related problem. Other possible causes such as sunroof drain problems are not covered here.
To determine if one or more doors is at fault, you’ll need to know how to recognize the common telltale signs. This is usually easy to do even with the interior door panel still in place. This is best done after a heavy rain or washing your car.Telltale Sign #1 – Water on the door sill.
In this first photo you can see that water is accumulating on the door sill and upper surface of the weather stripping. This is probably because it’s leaking in from under the water deflector. Once it reaches the door sill it’s free to run down into the floor pan. With various positions of the car and forward motion it’s not uncommon to find water under the carpet in the rear seat area, even if it’s originating from a front door leak.Telltale Sign #2 – Water leaking from under the door trim panel.
The other place to look is at metal door surface right underneath the interior trim panel. In this next photo you can see where water seems to be leaking down from behind the trim panel. This means either the water deflector is damaged, missing or has pulled away from the door. If you’re having trouble seeing any water here, you can also run the corner of some paper towel along the bottom of the interior trim panel where it rests against the door. If it gets wet anywhere along this area, there’s a water leak.Understanding how GM keeps things dry.
Next is to have an understanding of how GM designed the water deflector to keep moisture out of the passenger compartment. Doors are designed to be a “wet area” so it’s anticipated you’ll find water inside your doors. You’ll notice in the photo below how the plastic deflector is attached. Arrows show how water entering the inside of the door may hit the deflector and is channelled to the bottom of the door where it can drain to the exterior through drain holes.
The factory installed deflector is prone to pulling away from the door over time. If your vehicle was serviced (power window motor replacement, aftermarket speaker installation, etc), you are even more likely to have a problem with water leaks. From my experience, there are very few shops that seem to re-attach the water deflectors correctly so they won’t leak. The next picture is from a vehicle I serviced. There was clear evidence that someone had previously worked on the door (I believe to install some new wiring for aftermarket speakers). You can see how poorly the water deflector was reattached. There were several areas it was no longer in contact with the door at all.
This is a side view of the same door shown above. You can see how the deflector is completely pulled away from the door allowing for water to pass through to the interior.
This photo is from a rear door on the same car as the one pictured above. There was no evidence anyone had previously worked on this door but you can still see where the water deflector pulled away from the sheet metal and water passed down the inside surface of the door.The Repair Process
I’ve worked on several vehicles now and can complete all four doors in about five to six hours. You’ll want to make sure you leave adequate time because if you’ve never worked on these doors before you should anticipate it will take longer.Here’s what you’ll need:
1. Door panel / trim remover tool.
2. Small Needle nose pliers.
3. Ratchet w/ 10mm socket.
4. Torx T-27 screwdriver.
5. X-Acto knife (to cut the sealant tape).
6. Sharpie permanent marker (2002 and newer model year cars).
7. Bug & Tar remover.
8. Isopropyl alcohol or similar cleaner that won’t leave a residue. Windex will also work if others aren't available.
9. POLYshim Butyl Architectural Tape (sealant) – Approximately 7’ /door.
10. Supply of clean rags.
11. Twiddler Speaker Housing Retainer (optional) – 1 per front door.Step 1 – Remove the door trim panel.
Remove the twiddler (small speaker near the outside mirror). This is held on with one plastic push-in retainer close to the top of the assembly. GM recommends replacing this retainer every time the speaker is removed and reinstalled. The retainer (GM P/N 12065361) is a more brittle plastic than many other retainers and is easily damaged. It’s not uncommon for the speaker to rattle afterwards if you don’t install a new fastener.
Remove the trim around the door handle. These simply snap into place with four clips. Pull on the end farthest away from the lock paddle to start the process. There is NO need to remove the power window switch assembly.
Remove the door panel by inserting the trim panel removal tool between the door and the door panel. I recommend starting at one of the lower corners. Be very careful not to damage the covering on the door panel or scratch the paint in a visible area. You may want to wrap soft fabric around the end of the tool. The retainers emit a loud snap when they release. This is normal and there is no need for concern. With all the retainers released, you’ll need to pull the panel away from the door and lift at the same time. With the door panel off, unplug the wiring harness connector to complete the removal. Here are pictures of the inside of both a front and rear door panel showing the location of all retainers:
Once the door panel is off, there are two spring steel retaining clips that will remain attached to the door panel. You will need to remove these for use later in the reassembly procedure.
Use a pair of needle nose pliers to remove the two spring steel clips. You can see in the photo above that they are located on the hidden side of the panel behind the main grab handle. These provide extra strength when pulling the door closed. The clips slide into the white plastic retainers attached to the door with Torx screws and need to be put in place before reinstalling the door panel.Step 2 – Remove the plastic steel clip retainers and door module.
These plastic white retainers snap into the door where the grab handle portion of the door panel is positioned. A Torx T-27 screw spreads tabs on the back and prevents them from coming out of the door. Remove the screw and then pop the plastic retainer from the hole.
Unplug all connectors from the door module. Once this is done, use a 10mm socket or nut driver to remove the two nuts holding it in place.Step 3 – Mark position of existing sealant and drain hole location (2002 & newer or clear water deflectors only).
The 2000-01 model year water deflectors are not clear and you cannot see through them. They do have a ridge moulded into them that can be used as a guide for placement of the new sealant. The clear deflectors don’t have this groove so marking them is beneficial. This photo is a 2000 model year SSEi (courtesy Archon).
Use the Sharpie permanent marker to trace where you see the existing sealant. Also, trace around the drain holes at the bottom of the door. These steps need to be completed BEFORE you remove the water deflector from the door.Step 4 – Remove the water deflector.
Feed the wiring harness through the hole. There are two push-in retainers at the top which need to be removed. Pull the water deflector away from the door. I suggest starting at one of the bottom corners and working up the sides and then across the top.Step 5 – Remove old sealant.
This is a very important step and you’ll want to ensure all the old sealant is gone before proceeding to the next steps. If you’re able to get a little off initially, you can create a small ball of adhesive. Use this ball to stick to what remains on the deflector and/or door. Pull away sharply to aid in cleaning the remaining sealant off.
Once the majority has been removed you can use Bug & Tar Remover to clean off any residual sealant. I have used a few different types but highly recommend Turtle Wax brand in a non-aerosol pump spray container. This has been the most effective and least noxious of any I tried.
Now you should wash the water deflector in a shallow bath with mild soap. Rinse it well with clear water afterwards to make certain any residue from the soap and Bug & Tar Remover is gone. Ensure it is completely dry before proceeding to Step #6. You don’t want anything to prevent good adhesion of the new sealant. Likewise, use isoproply alcohol (Windex or other cleaners that won't leave a residue are also alright) to clean the surface of the door itself. These evaporate well and leave a very clean surface for the new sealant.Step 6 – Install new sealant.
The new sealant is made by Tremco and called POLYshim Butyl Architectural Tape. There are different sizes available. For this application 1/8” thick is best and IIRC it comes in 40 foot rolls. There will be enough to do all four doors with a little left over. It is distributed at a wholesale level by C.R. Laurence Co., Inc. They will only sell to companies who have an account with them so I had to purchase it from a local glass shop. It's used mostly in commercial glass applications, not automotive. The CRL item number is 7241XC3 in case this will help your local shop. You may contact C.R. Laurence directly to find a nearby retailer by visiting their website at http://www.crlaurence.com
and folowing the appropriate links.
This step is best performed by two people (although you can do it alone if needed). Make sure you apply it to the correct side of the water deflector. Start at the top, somewhere near the centre. Use one continuous length around the entire perimeter.
The tape bends around corners easily but you need to remove the wax paper backing to do this. I recommend one person holding the roll above the work area while another carefully applies the tape to the plastic deflector. Try to handle it by the edges so as not to get oil from your fingers on the bonding surfaces. Make sure you carefully follow all contours of the water deflector. You don’t want to leave any gaps where water can penetrate. The rear doors require more attention to this than the front. Each door will require about 7 feet of sealant tape.
Here you’ll see the tape is applied and the water deflector is ready for installation on the door. You can see where I traced around the drain hole. It’s best to make sure the tape comes right up to the bottom so water can’t collect between the deflector and the sheet metal surface of the door.Step 7 – Install water deflector on the door.
This is also best done with two people but again can be done with one if necessary.
While holding the bottom of the water deflector away from the door, attach it at the top with the two push in retainers. Continue to hold it away at the bottom and sides while pressing the new sealant against the door along the very top edge. Start in the centre and work outwards.
Carefully feed the wiring through the hole while trying to keep the sealant on the remaining three edges away from the door. Once this is done, grasp each lower corner. Pull downwards and outwards gently. Start on the bottom edge, again working from centre and press firmly against the door. You can the press each of the sides against the door and create a seal. You can now use your thumb and index finger to press the sealant against the door one last time. Keep the sealant tape between your thumb and finger as you work your way around the door.
You’ll see in the next photo there are some small air bubbles. These are inconsequential and won’t allow water to penetrate because of how wide the tape is.Step 8 – Reassemble the door.
1. First, bolt the door module back in place and plug all the connectors in.
2. Snap the two white plastic retainers into the door. Make sure that the green paint is at the top. You can also see the word “TOP” embossed in the end.
3. Install the Torx screws into the two plastic retainers.
4. Slide the spring steel clips into the retainers. The photo shows the door handle clips correctly installed.
5. Plug the door trim panel connector into the door harness.
6. Reinstall the trim panel. The metal edge along the top of the trim panel needs to clip overtop of the black metal strip running across the top of the door at the base of the window. Once you do this, you can carefully position all the green retainers in their mating holes. You may need to wiggle the door panel slightly so the spring steel clips in the centre line up properly behind the door handle.
7. Firmly press the door panel into place.
8. Re-install the door handle trim. Connect any wiring as required on the front doors.
9. Re-install the twiddler speaker. As mentioned, replacing the white plastic retainer is recommended.A few last notes...
If you’ve had a lot of water accumulation on the floor, you may want to consider removing your seats and lifting the carpet to ensure it adequately dries. Depending on how long the water leaks have been a problem, your floor pan may require attention.
You should also inspect the weather stripping around your doors. If it is deformed or damaged in any way you may need to replace it. The photo below shows an area that could result in a water leak. You can see how the weather stripping has been deformed. If this occurs you'll need to replace the weather stripping.
To keep your door seals in good shape you should clean and condition them on a regular basis. I use Meguiar’s Mirror Glaze (Professional) Series #40 Vinyl & Rubber Cleaner/Conditioner. This product can also be used on many other interior surfaces.
Alternatively, you can use this product (available from your local GM Parts Department). My local dealer uses this to condition all the weather stripping.
Hopefully this will help you to stay dry and achieve a Bonneville without the Non-RPO Pool Option!