By Chuck Hanson
It's hard to believe, but summer's already over. For many, the end of the cruisin' season signals the beginning of the busy "fix it" season. Many of those little things that were merely annoyances at the start of summer, somehow turned into major headaches that are screaming for attention now. The power lift mechanism on our Chevelle's power top mechanism is an excellent case in point.
At the beginning of warm weather, we laid our top down for the first time, only to find out that the seals in our lift cylinders had deteriorated over winter, and were leaking fluid each time we'd press them into service. The leaks weren't that bad at first; we were able to keep the fluid topped off by checking and refilling the reservoir every other week or so. Inevitably, the leaks became worse and the refills more frequent, until we simply quit operating the top every time we took our Chevelle out for a topless cruise. Instead, we just let the top lay in the well for the rest of the summer.
But with those warm, topless nights fast fading into only memories, we've decided to deal with the reality of getting our lifting mechanism back in top working condition.
Since we knew our cylinders were leaking, we ordered a replacement pair from the Original Parts Group (17892 Gothard Street, Dept SC, Huntington Beach, CA 92647-9910 (800) 243-8355), along with a complete set of pump-to-cylinder hoses, a new pump cover, and just for grins, a '66 Chevelle convertible top operator's manual. Now, after completing the repair, we find ourselves eagerly anticipating summer again, when our power top mechanism will lift our lid as easily as it does our spirits.
 1. OPG, Inc has everything needed to get your power top mechanism back in working order, including new pump assemblies. Ours checked out fine, new cylinders and a hose kit were the only items required. We also replaced our tattered pump cover and added a folding top operator's manual to the glove box documentation. |
2a&b. Accessing the lift cylinders is accomplished by removing the rear seat cushions and armrest assemblies. The bottom cushion is dislodged by pushing it towards the rear of the car, then lifting up on the front edge. 
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 3. A Fisher body manual came in handy to help troubleshoot the system as well as pinpointing all the attaching points and hardware. It also outlined the procedure for extracting the cylinders once they are loose. |
4a&b. We located the special mounting bolts and removed them. Be sure to get the ones to the inside as well; they're somewhat hidden and are only accessed with a combination wrench. The lifting ram attaching bolts are easily accessed, but only after raising the top. Since our power mechanism was inoperative, we raised it by hand before removing the bolts from the frame assembly. |
5. Once the three bolts (per side) are removed, the next step is to loosen and detach the hose assemblies. Then you can extract the cylinders through the top opening in the power top housing. |
6. The replacement cylinders from OPG, Inc are slightly longer than the originals. We test fitted them first, and after checking clearances, bolted them in place. |
7. Plumbing the cylinders was a snap, too. Although we actually routed and connected the lines after the cylinders were installed, this photo illustrates the proper connections: the tops of the cylinders are connected to one line, while the bottoms tie in to the other line. Both lines connect to their respective fittings on the pump. |
8. There are two of these special bolts retaining the cylinder in its location in the power top mounting bracket. The inside one is the toughest to get to. Make sure the nylon mount bushing remains in place during reassembly or you'll have all kinds of rattles back there, and excessive play every time the power top is operated. |
9. We fashioned a special funnel for filling the pump reservoir by inserting a 6-inch piece of 1/4-inch vacuum hose into the end of our smallest funnel, then retaining it with electrician's tape. The GM manual calls for the system to be filled with brake fluid, so be careful not to get any on painted surfaces. |
10. You have to operate the top through several lift cycles to ensure the reservoir is properly filled; the manual suggests 1/4-inch below the filler opening. Once the reservoir was full we simply installed our new pump cover and the rest of the interior. |
1998 Electronic pages by AL