GM "Scissor Top"
Convertible Top Parts, Diagnosis and Repair

1971-1976 Hideaway Top Problems?

GM Convertible Top Operation and Troubleshooting

HISTORY

A NEW CONVERTIBLE TOP DESIGN

The convertible body style was very popular from the early days of the automobile until the mid- to late sixties, when sales began to drop off due to an increase in highway driving and the introduction of sporty new hardtop models. The popularity of vinyl roofs, which simulated the appearance of a convertible with the top up, and the comfort of factory air conditioning and stereo sound systems also contributed to the decline of the convertible body style.

In 1971, General Motors (GM) introduced a new convertible top design for some of its cars that they named the Hideaway Top. This design differed from previous designs in the manner in which the top side rails folded while lowering the top. Previously the side rails collapsed straight back, accordion style, which required a smaller width rear seat to allow space at each end for the top frame components with the top folded. This also created a more compact area for rear seat passengers, and usually required shorter rear seat side arm rests which meant less elbow room for rear passengers.

The new design, often referred to as a "scissor top" was engineered so that the side rails moved inward, toward the center of the top as it lowered, which meant it was no longer necessary to allow room at the sides of the rear seat for these components, as they now stacked behind the rear seat with the folded top. In addition to increased rear seat roominess, appearance was improved as the boot was able to sit nearly flush with the car body.

APPLICABLE MAKES AND MODELS

GM used this design for its convertible body style from 1971-1976 on the following full sized makes and models:

1971-1973 Buick Centurion
1971-1972 and 1975 Buick LeSabre Custom
1974 Buick LeSabre Luxus

1971-1976 Cadillac Fleetwood Eldorado

1971-1972 Chevrolet Impala
1973-1975 Chevrolet Caprice (new model for '73, replaced the Impala; became the Caprice Classic in 1974)

1971-1975 Oldsmobile Delta 88 Royale Convertible

1971-1972 Pontiac Catalina
1971-1975 Pontiac Grand Ville Convertible

OF NOTE:
1965-1969 Chevrolet Corvair Monza Convertible
(A power convertible top was an option, and some of the electrical components, such as the top motor, are similar to those used on the later GM convertible models.)

LAST CONVERTIBLES

The final day of production for factory convertibles of this era:

Buick LeSabre Custom—researching
Cadillac Eldorado—April 21, 1976
Chevrolet Caprice Classic—researching
Oldsmobile Delta 88 Royale—July 11, 1975
Pontiac Grand Ville—researching

REPAIRS

PARTS AND PART NUMBERS

Top Motor (GM Part 22049793, Interchange 5405632)
Top Transmission (GM Part --)
Lock Assembly RH (GM Part 9623938)
Lock Assembly LH (GM Part 9623939)
Drive Cables (Large)
- RH (GM Part 9874738)
- LH (GM Part 9874739)
Actuator (Side Gears)
- RH (GM Part 9606712)
- LH (GM Part 9606713)
Side Tension Cables (Small; with Spring and Pigtail)
- RH (GM Part 9607018)
- LH (GM Part 9607019)
Top Relay (GM Part 9875101)
Top Control Switch
- Buick (GM Part --—1971-1974; 1247201—1975)
- Cadillac (GM Part --—1971-1973; --—1974-1976)
- Chevrolet (GM Part 6270643—1971-1974; --—1975)
- Pontiac (GM Part --—1971-1975)
- Oldsmobile (GM Part --—1971-1973; --—1974-1975)
Wiring Harness
Ball Joints
Hard Boot Bag (1972-76 Eldorado; GM Part 9617133)
Hard Boot Locking Pin (GM Part --)
Top Frame Header Guide Pins (GM Part --)

LOCATING PARTS

Links to current eBay auctions are provided in the right column to assist you in locating parts. We've been able to find many rare, obsolete, NOS (new old stock), NORS (new old replacement stock), and reproduction parts on that site over the years. We recommend you check the seller's feedback before bidding or buying, and don't forget to provide feedback on your experience after your purchase, as it helps to identify sellers who truly do value your business, as well as those who don't. (We normally recommend dealing only with sellers who have a high feedback rating.)

CONVERTIBLE TOP COLORS

Factory top colors varied with the year, make and model of the car. Black and white were offered on most of these cars, and could be ordered with any exterior color.

Black, White, Light Beige, Dark Blue, Dark Green, and Dark Brown were available on the Eldorado for 1971. Dark Green and Dark Brown were eliminated for 1972, but a new color, Covert (a medium gold shade), was added, and those colors remained the same for 1973. In 1974, Light Beige was replaced with Sandalwood, Covert by Maize, and Amber and Terra Cotta were added. For 1975 you could also get Graystone, Yellow, Dark Red, or Orange. Amber, Terra Cotta, and Maize were dropped. In its final year, the Eldorado convertible top added Dark Blue-Green, Firethorn, Buckskin, and Ivory to the list of colors, and parted with Orange, Yellow, and Graystone.

OPERATION

TOP OPERATION—LOWERING TOP

1. To lower the top, first check the top well behind the rear seat for articles that could interfere with or damage the top as it folds down into the area. Lower both sun visors and all side windows.

2. Rotate the two top locking handles which are located on the top side rails above the front door glass inward to release the locks from the windshield header. Leave the locking handles in the unlocked position until you are ready to lock the top to the windshield header again, as the lock assemblies and/or top frame can be damaged if they're moved back to the locked position before lowering the top.

3. With the engine running, press the convertible top switch located on the instrument panel toward "DOWN" or "DN", and hold in this position until the top is fully lowered. Note: It is a good practice to stop the top before it's fully lowered and reposition any top material that isn't folding properly to avoid potential damage to the top.

4. Once lowered, relocate any top material that remains outside of the top well to avoid damage or interference with the installation of the top boot.

5. Depending on the model, either a hard or soft boot was provided to cover the lowered top. (The Convertible Hard Boot was a new $40 option for the 1972 Eldorado.) The soft boot installs by sliding the rear edge of the boot under the chrome molding near the base of the top, with snap retainers on the sides, and with velcro along the front edge. The hard boot comes in two pieces, with a storage bag for use when not installed on the car to prevent paint damage. The passenger side of the hard boot must be installed first, beginning with placing the rear edge of the boot under the chrome molding at the forward edge of the top well. The driver's side then attaches in a similar manner, and fits under the passenger side boot where they meet in the center. Two chrome rings hold the front outboard edges firmly in place. Consult your vehicle's owner's manual for more specific installation procedures.

TOP OPERATION—RAISING TOP

1. Remove boot, if installed.

2. Lower both sun visors and lower the side windows at least partially.

3. Press top control switch to the "UP" position and hold until top raises and comes to a stop above the windshield header.

4. Lock the left side of the top first by pulling the left side of the top front header bar down to engage the guide pin on the top frame with the hole in the windshield header. While holding the top down, rotate the lock handle outward to the locked position.

5. After locking the left side, pull down and align the right side of top to the front header bar, engage guide pin in its hole, and rotate the right lock handle outward to locked position. BE CERTAIN TOP IS SECURELY LOCKED TO WINDSHIELD HEADER PRIOR TO DRIVING CAR. (Failure to do so can cause damage to the top material and/or frame.)

DIAGNOSIS/REPAIR

Top Stops Moving During Operation (Raising or Lowering)

The circuit breaker could be tripping, which interrupts the power supply to the circuit by design. This will cause the top to stop before completely raising or lowering. Usually, after a period of time, the breaker will reset itself and allow you to complete the raising or lowering process. The breaker itself can go bad, or another electrical component can draw too much power, resulting in the breaker opening. Check to see if the top switch gets warm when operating the top. It's somewhat common for the switch to go bad. A loose connection, corroded or loose ground, or a damaged wire can also be responsible.

(More diagnosis and repair tips coming soon.)

CARE AND MAINTENANCE

CLEANING THE TOP MATERIAL

(These instructions are for convertible tops made of vinyl, not the canvas or cloth type.)

Clean the top in a shady area out of direct sunlight, and make sure the top isn't warm to the touch from sun exposure. If it is, let it cool completely before cleaning. There are commercial products available designed to specifically clean and care for convertible tops, but mild soap and water usually do a good job as long as the top hasn't been neglected. We don't recommend using dish washing detergent, as this can strip wax off of painted surfaces.

Wet the top with cool water, and apply the soap in a circular motion to a small section using a clean soft sponge, towel, or mitt designed for washing an automobile. Allow it to sit briefly to break down dirt or organic matter that may be on the top. Apply more soap and rub in a circular motion again to remove the grime that has been loosened, then rinse thoroughly. Continue until the entire top has been cleaned. If you notice any areas that are still dirty, apply more soap and gently scrub the area using a soft nylon brush. Vinyl upholstery cleaners may be necessary for badly soiled or stained areas, and if you choose to use them we recommend you follow the instructions provided for their use. The brush can be used to work the cleaner into the textured vinyl, but make sure you don't allow the cleaner to contact chrome or painted areas for very long, as it can also remove wax or discolor some trim.

Allow plenty of time for the top to air dry before lowering it.

REFERENCES

- 1972 Cadillac Owner's Manual
- 1973 Cadillac Owner's Manual
- 1974 Oldsmobile Owner's Manual (Delta 88, Delta 88 Royale, Custom Cruiser, Ninety-Eight Luxury, Ninety-Eight Regency)
- Fisher Body 1971 Folding Top Service Manual "B & E" Bodies (GM Part 8704198-A)
- Fisher Body 1971 Service Manual
- 1976 Cadillac Shop Manual
- 1976 Fisher Body Manual (GM Part 9632833)