Since our last installment, we've put several hundred miles on our "Shoestring" C5's odometer and had a chance to get better acquainted with the car's first round of upgrades. Thanks to the new drivetrain components from Fidanza, SPEC, and Mid America Motorworks, the engine revs more quickly, and the clutch pedal engages with both less effort and greater precision.
Now that we've improved the car's drive-ability, we'll be using this month's story to focus on a couple of traditional C5 trouble spots. We decided to begin with the weatherstripping. During our initial inspection, we were surprised to find that the only problematic area seemed to be the outermost upper corner of the B-pillar seal. This strip runs from the rear of the driver door around the front of the targa bar and over to the rear of the passenger door, providing a waterproof seal for the top and windows. The wear here was most likely due to the repeated removal and reinstallation of the roof panel.
Locating a replacement was easy, thanks to Corvette America's 481-page Master Catalog. The company offers every seal originally fitted to the fifth-generation cars, both individually and in cost-effective kits. After a quick browse through the catalog's C5 section, we decided that PN 38949, (Weatherstrip, Roof & Window Rear Coupe; $125) was exactly what we needed.
Upon receiving the new seal, we compared it with the (still-installed) factory piece to verify fitment. In doing so, we quickly realized this job was perhaps best left to professionals with the experience and specialty tools needed to do things right. Once again, we chose the folks at Bill Buck Chevrolet's Corvette Connection, in Venice, Florida. We got in touch with body-shop manager Claude Bates, who fit us in quickly and assigned Lead Master Tech Paul Heavner to the project.
With shop time scheduled, we decided to go ahead and take care of another urgently needed exterior repair. As is the case with many regularly driven early C5s, our car's side mirrors had become loose. In doing so, they lost the full range of adjustability that is so important to obtaining a proper rear view. At first we hoped to find a repair procedure we could use on the original mirrors, but we had no luck on this front. A subsequent Internet search for a set of lightly used mirrors proved similarly disappointing.
Once we resigned ourselves to purchasing new units from GM, we were pleasantly surprised to find that the parts cost only $335 for the pair. (They carry GM PN 10416055 and PN 10416056). In fact, the additional amount we spent for the new mirrors (as compared with the originally projected cost of repairing the used ones) was not nearly as high as we expected. The new units actually proved the best way to go, since all the parts were fresh, and we didn't have to worry about preexisting damage or wear.
Let's follow along to see how the professionals go about installing these new pieces.
Before removing the old weatherstripping, it is a good idea to lay the new piece in the sun to make it a little more pliable. You will most likely find several small pieces of tape applied to the mating surface of the new stripping. This covers the manufacturer-applied adhesive and should not be removed until after you have test-fitted the new seal and are ready to install it permanently.
Carefully remove the hold-down screws at the bottom of the original seal and gently pull the seal away from the mounting surface. You will see a number of trim retainers that can be removed with a "horseshoe"-type tool. Count them before removal, so you'll know you have them all. Then gently pull them out, taking care not to lose them. They will be needed to install the new seal.
Finish extracting the weatherstripping from the seal slot, then clean out any residue or debris that's found its way into the channel. Now is the time to perform that test-fitting. Make sure all the retainers are handy and begin securing the new seal within the channel. You'll need plenty of patience, as this job tends to be more difficult than it first appears.
Make sure the seal seats fully and the outer surface fits flat and smooth along the targa bar. If it doesn't, you'll need to back out the seal to where the lip can be reinstalled correctly. You may have to do this several times, so don't become discouraged. Even the most experienced techs go through this process on a regular basis.
(Note: If you don't have the job-specific installation tool, use a body-putty trowel instead. With its tapered surface, the trowel can aid in compressing the seal in such a way as to ease the inner lip into the slot.)
Next, move on to the mirror assemblies. After removing them from their boxes, separate the mirror glass from the housings, and disconnect the electrical leads that actuate the four-way power function. Once they're removed, be sure not to get the two mirrors mixed up. Mask off all the power leads and internal mechanisms. Don't skimp on the tape, as any overspray here could cause the power functions to fail almost immediately. The mirrors are now ready for painting.
Next, begin disassembling the car doors to gain access to the mirrors' mounting points. Power down the windows on both doors. This allows you to remove the window/door trim pieces. With this done, begin removing the interior door panel. There is a small plastic cover just inside the door pull. This piece is easily broken when removed, so be careful when popping it out.
Unscrew the two screws that become visible when the pull is removed. Follow this step by removing the controls for the windows and mirrors and the cover over the interior door-handle assembly. Pull these out slowly, disconnecting the electrical leads before completing removing them.
The door panel is now ready for removal. There are screws at the upper outer edge that run into the rubber door moldings. These must be unscrewed. The door panel itself can then be gently pried out and up, using a specialty tool (available at most auto-parts stores) to pop out the fasteners. Be careful when prying away the panel, as you can break the mounting areas that hold these plastic fasteners into the door panel. Once the panel is free of the door, fish out the electrical harness and place the panel somewhere safe nearby. You'll see two rubber door plugs near the inner-door handles. Remove these for access to the inner-mirror housing nuts.
Note: You may want to keep the window controls close at hand, as raising and lowering the door glass can aid you in removing the mirror harness. Once the harness has been freed, unbolt the three nuts holding the mirror in place and pull the mirror off the door, carefully fishing out its harness from within. There are two harness clips that should be removed from these harnesses before pulling them out of the door, as they will not fit through the opening. These need to be reused, so hang on to them. All that's left now is to install the new mirrors and reverse the process of removing the door panels.
Let's follow along as Paul Heavner completes both the weatherstripping and side-mirror replacements on our Shoestring C5.
Check back for the next phase of our project, when we upgrade the brake system to match the C5's newfound performance . . . and the horsepower enhancements to come.