As we've said from the beginning of this project, missing parts are normal with a basket case car. We were lucky; we are up to the fourth installment of the story of this Chevelle's rebirth at Muscle Car Restorations in Chippewa Falls, Wisconsin, and the only major parts to come up short so far are the side glass.
Now, glass can be polished, and if there are no major scratches, polishing could be valid approach. But since we were missing pieces and didn't want to mix old and new, Original Parts Group was contacted for new windows and mounting hardware. The window regulator mechanisms themselves were in restorable condition, so those were reused.
It's surprising how water can find a way through
It doesn't matter if the door and window seals are with the basket case. Don't even think about trying to reuse 40-year-old gaskets when a call to a company like SoffSeal can provide brand-new, perfectly fitting pieces. Since we are dealing with a hardtop, the door adjustment plays just as critical a role as the window adjustments do for a proper seal, so that will need to be done first. In fact, it's a very wise idea to mock up the gaskets, doors, and glass before the car is painted to be absolutely sure that everything will fit and to make adjustments if everything doesn't.
A word about the door and window seals. It really doesn't take a lot of pressure for them to achieve a watertight seal, but, like any other rubber type product, they will "take a set" and conform somewhat to their sealing surface. So it's OK for them to be a little tight at first. If, however, it takes a hard slam to shut the door or a very tight window to stop a leak, then something is not adjusted correctly. If the glass is running parallel to its gasket, then it really shouldn't take a lot for it to seal tight. What doesn't work is needing to have a window too tight on one end in order to bring the glass in contact with the seal on the other. This is the sort of thing that usually can be prevented by doing a prepaint mockup.
To test the seals when they are done, Muscle Car Restorations will take a hose to all the windows to be certain there are no leaks anywhere. It's surprising how water can find a way through where you'd swear there was no way it could. Better to find out in the shop than on the road at 60 mph.
Don't even think about trying to reuse 40-year-old gaskets
1 The glass from Original Parts Group comes with all the hardware attached. The three studs in the center mount the glass to the regulator, while the two clips on either end hold the stops that limit upward travel.
2 Here you can see all the provisions for door glass adjustments: (A) window height stops (there are two of these, though only one is visible in the photo), which limit how far the window can rise; (B) the fore and aft adjustments; (C) the tilt adjustment, which moves the top of the glass in or out; and (D) the rotation adjustment, which aligns the top of the window with the roof (along with the height stops) and also with the quarter window.
3 Install all the door hardware, including the door latch and lock and window crank, before you install the glass. Note that the glass bolts to three slotted holes, which also provide the fore and aft adjustments.
4 Window guides on both ends keep the glass from falling inward when the door is open or the window is partly down. The guides don't really affect the glass adjustment when the door is closed and the glass is up.
5 A vertical stop on both ends limits upward travel. These also set the final fore and aft rotation when the glass is fully up so it aligns with the weatherstrip and roof.
6 Start by aligning the leading edge of the glass with its weatherstrip, then fine-tune the overall height. Note that raising the height will also move the leading edge forward a bit. The top of the glass will also need to be tilted in and out to get the leading edge of the glass parallel to the weatherstrip so it has even contact along the entire length.
7 Here you can see that the back corner of the glass is just a bit too high, causing it to fold over the weatherstrip when the door is closed with the window up. This actually fit fine until the quarter-window was in place, so don't be surprised if there is some fussing around to do with both windows after the initial adjustments. Also, it's equally important to check the fit from the inside and roll both windows up and down with the door closed.
8 Don't forget to raise the down stop to the bottom of the window when you have it in the preferred down position.
It's important to check the fit from the inside and roll both windows up and down with the door closed
9 As you might expect, the quarter-window glass adjustments are totally different from the door glass. The two cadmium-plated bolts on top allow the bottom of the window to move in and out and allow a small amount of twist as well. The black bolt on the left is the up stop. The two brown bolts (inside the panel) allow fore and aft movement within the slots you see there.
10 The Phillips-head bolt is the down stop adjustment. The black bolt and small slot near the bottom tilt the top of the window fore and aft.
11 This slot tilts the top of the window in and out.
12 Obviously this gap is not what we're looking for. The rear window will need to move forward to fill the opening.
13 The first step is to get the quarter-window edge to line up with the door glass and close enough for it to cause the door window to seat well into the quarter-window weatherstrip.
14 The quarter-window also needs to be adjusted so that it is parallel with the door window. Here you can clearly see that the bottom of the window must be moved outward.
15 As the door window goes up, it also moves rearward. Be sure the quarter-window glass is adjusted so that the door glass catches the outside of the rear weatherstrip as it is raised.
16 Lubricate the shaft and the channels with white lithium grease, and run both windows up and down through several cycles to be sure everything works as expected.
