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I've got a 72 cutlass and am in the process of sorting out why there is suddenly no power to the convertible top switch. I did get some suggestions in another thread that I plan to follow.
For now, and since I have the potential of rain in the near future, I'm wondering if anyone knows if the top can be operated manually. I definitely don't want to force it if it cannot be done manually. Ideally, I'd like to close it up now and troubleshoot my issues with the switch as time allows.
Each (one) hydraulic (ram) cylinder is located behind each rear passenger armrest on each side (refered to as the folding top compartment side panel assemblies). Remove each assembly to expose each hydraulic cylinder. I believe there are about 6-8 screws holding each folding top compartment assembly in place.
I guess I should mention each entire folding top compartment assembly is actually comprised of two pieces - the armrest (itself) and the piece behind the armrest. The pieces are held together via a couple screws (which you cannot see from the exterior). Once you remove the entire folding top compartment assembly, you'll see how the armrest is fastened to the larger piece behind the armrest.
Electrically, my top switch is wired using a thick (maybe 10 gauge) orange wire with black stripe to a firewall mounted 40 amp circuit breaker which goes right to the battery. It's not a key-switched circuit so I can raise and lower the top with the car off. Olds may have changed that later, but I like it being battery connected. The dash top switch is a heavy amp switch with thick "up" and "down" circuit wires running to the pump motor.
If you can, get the pistons in the down position, then you can raise and lower the top manually, at least temporarily. In the 80's somewhere my top motor or one or both of the hydraulic rams failed and I raised and lowered it by hand for a while.
To get at the hydraulic rams/cylinders/pistions, the process is to remove the piston covers (some call them rear quarter interiors). First pull the rear seat bottom, then the rear seat back. Then the upper and lower piston covers: on each side there is an upper and lower piston cover which can be quickly removed with a makita using a phillips head. Once you can see the hydraulic rams, you can see where they are in their up/down travel. There are two top bolts which physically connect the rams to the top itself. Remove those top two bolts and you can move the top manually by standing in the middle of the rear seat and pulling it up & down as you like. It's a little heavy, but not terrible. Just don't strain your back pulling it up. I'm guessing Cutlass tops weigh a bit less than 98 tops.
If the hydraulic rams aren't in their lowest position, they may block the top mechanism from going up & especially down. So you might have to remove them entirely to make manual operation easy. To remove them find the 2 bolts on each ram about 3/4s of the way up each ram which connect them to the car body. Each ram has an outer (closer to the exterior of the car) and an inner which you can see once the piston covers are removed. Pull those and store the rams safely beneath the rear seat and you're off & running with a manual top.
Over the longer term, you'll probably want to make it electric/hydraulic again. The pump is pretty simple. Just pull it, clean the reservoir and pump thoroughly with your favorite solvent. Or maybe just a bunch of transmission fluid and spare vacuum lines that seal. Cobble up a bench system to run the pump in each direction for a bunch of runs to get any shavings out. You may need to get a new revservoir-to-pump O ring seal. See your local Hillman hardware display or get the right O ring online. They're cheap so get 2 in case you over-torque the reservoir to the pump motor.
Over frequent repeated runs be aware the pump can get hot. Don't get it too hot or it might burn out. Take your time and have a lot of paper towels to clean up the mess in case you knock over your clean out reservoirs...
You might need new rams, these are available from Convertible Service in LA or a specialist in Florida. Or maybe OPGI too. Anyway not too hard to find.
In my '66 GM used brake fluid. In later years they switched to transmission fluid. This time around I went with transmission fluid if only since it won't eat paint in case the system leaks. Plus maybe there's some useful lubrication in tranny fluid that brake fluid doesn't have. Probably not a good idea to mix brake and tranny fluid. If in doubt stick with original to your car, just make sure it's real clean original stuff.
If you're doing the rams, consider new plastic high pressure lines too, but don't run dirty fluid through new lines or new rams. Dirty fluid will harm the ram seals and could hurt the lines too. That's why you want a clean or new motor too. Original GM lines lasted on my car for at least 40 years, the reproductions are good, but I don't know yet if they're as good. When installing the plastic lines don't over-torque the soft brass fittings or you'll need yet more new lines...
I just did my 98 over the Summer. You'll want 4 or 6 hours to go carefully enough to make everything work and look right.
I've probably missed some tricks, but I hope this covers the basics of manual operation and back again.
If you don’t have one, surely someone you know can spare a spot for a bottle of decent scotch...
Manual manipulation of the top is a bona fide pain in the a$$......and that’s after you pull the rear passenger compartment apart. Ask me how I know this.....
If it were me, I wouldn’t go that route if at all avoidable.....and if I did, I’d probably (if they are original ) replace the cylinders and hoses under the MAW principle.
Here are some pictures of my car with the seat and side panels removed so you can see the hydraulic cylinders and where they attach to the top frame assembly.
Last edited by Fun71; October 14th, 2019 at 08:23 PM.
Personally, I believe you'd be better served to first perform the ELECTRICAL CHECKING PROCEDURE as outlined in Post #8 to determine if that toggle switch is bad. And, if the toggle switch is bad, and you have current flowing to the motor (if you haven't checked this aspect, as yet), it's a simple maneuver to get current to the motor (following the directions) and then just pulse the convertible top up. It would be far better than removing the bottom seat, the rear of the back seat, and then the folding top compartment side panel assemblies. You can do what you like, but you'd be wasting a ton of time if you found out the issue was electrical and all you needed to do was replace that toggle switch. In the least, check to see if you have current/power to the motor. Follow the instructions. It's an easy enough scenario to direct wire to the motor and get the top to go up. But, again, test the current first to see if you have power at the switch and then beyond the switch to the motor.
For a complete answer, if you disconnect the hydraulic lines then fluid (oil) will spill out into your trunk or rear footwells, depending upon which lines you disconnect. If you must disconnect something, it should be the upper attaching bolt where the hydraulic cylinder rod connects to the top frame.
Last edited by Fun71; October 15th, 2019 at 07:24 PM.
October 14th, 2019, 01:44 PM
