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Hey all is there a way to manually adjust the up and down movement on the power bucket seat for a '72 Supreme? My driver side seat sits about a half a head rest higher than the pass side, which was fine until I got the seat re upholstered. Now my head is maybe 1/2 inch from the headliner. The up/down function for my power seat doesn't work correctly, so no go with that.
You would have to take the seat back out and disconnect the up/down cable. If you disconnect the cable from the transmission, you could turn the cable with a drill to adjust the seat. If you disconnect the cable from the track, you can use a square drive screw drive bit the same size as the cable on a drill to adjust the track. Either way, you will likely need to remove the track from the seat. Why does the up/ down adjustment not work on your seat? Does the motor run when you try up/down?
I would think the transmission my be stuck. Have you tried taking it apart to clean/ lube the gears and check the solenoids? The transmission has a small shaft that the belt/ pulley from the motor spin. That shaft powers two larger gears in the trans (one for up/down and one for front/ back). When you move the switch, the switch does two things. It powers the motor in the direction you want to move AND it powers the solenoid in the trans for the movement you want to operate (up/down or front/back). When the solenoid is powered it forces a metal cylinder out of the solenoid and engages a shaft onto the gear in the trans. Each cable has its own shaft and gear. These tracks were lubricated with white lithium grease from the factory, but the problem is that white grease gets hard over time and can cause the engaging mechanisms to stick. I always try to use a wheel bearing type grease or what you might find in a grease gun when I rebuild these mechanisms, because I have found that type of grease to not get hard over time. White grease can even get hard within a few years. I have assemblies that I have rebuilt and a few years later had to take them back apart, clean and re-grease them due to the white grease getting hard. You can test the solenoids with 12 volts. With the transmission assembled, ground the transmission housing, and apply power to each wire in plug from the trans separately. There are only two wires. One powers the up/down solenoid and one powers the front/ back solenoid. Apply power to each wire and spin the front pulley by hand. One wire should cause one of the shafts to spin when moving the pulley and the other wire should cause the other shaft to spin. I would still take the trans apart to clean and re-lube everything either way. Let me know if this makes sense.
I would think the transmission my be stuck. Have you tried taking it apart to clean/ lube the gears and check the solenoids? The transmission has a small shaft that the belt/ pulley from the motor spin. That shaft powers two larger gears in the trans (one for up/down and one for front/ back). When you move the switch, the switch does two things. It powers the motor in the direction you want to move AND it powers the solenoid in the trans for the movement you want to operate (up/down or front/back). When the solenoid is powered it forces a metal cylinder out of the solenoid and engages a shaft onto the gear in the trans. Each cable has its own shaft and gear. These tracks were lubricated with white lithium grease from the factory, but the problem is that white grease gets hard over time and can cause the engaging mechanisms to stick. I always try to use a wheel bearing type grease or what you might find in a grease gun when I rebuild these mechanisms, because I have found that type of grease to not get hard over time. White grease can even get hard within a few years. I have assemblies that I have rebuilt and a few years later had to take them back apart, clean and re-grease them due to the white grease getting hard. You can test the solenoids with 12 volts. With the transmission assembled, ground the transmission housing, and apply power to each wire in plug from the trans separately. There are only two wires. One powers the up/down solenoid and one powers the front/ back solenoid. Apply power to each wire and spin the front pulley by hand. One wire should cause one of the shafts to spin when moving the pulley and the other wire should cause the other shaft to spin. I would still take the trans apart to clean and re-lube everything either way. Let me know if this makes sense.
When I had the transmission off while getting the seat redone, I did some trouble shooting.:
1. Cleaned and greased the tracks
2. Tested the switch with a multimeter ..tested good.
3. Disconnected all the cables from the transmission and lubricated them.
4. Disconnected the cable from the up/down mechanism and operated the switch...the cable turned, so at this point I deducted it was the up/down mechanism at fault.
5. Tried to move the up/down mechanism by turning the hex nut on the worm gear..got nothing.
6. Decided to call it a day and put everything back together, since I never move the seat anyway, knowing as long as I get it back in the same position as when I started, I'd be ok.
Did I miss anything?
My reasoning at this point is since I had a new cushion installed, it's "firmer", thereby putting my butt higher in the seat...would that be correct?
Oh, one more thing, I noticed the seat has a slight forward tilt to it as well. I'm thinking if I can get the rear portion to tilt downward, it'll even things out, but again, how?
Here's another thought...as a temporary fix (until I can dive back into it), if I shimmed the front of the seat up, would it lower (or "pivot") the rear of the seat down?
Before you do anything else, go back out and try the up/down movement again. First, move the front/back adjustment so that the seat is in about the middle of its range. Then run the up/down adjustment. If the front/ back movement is sticking in the transmission, the up/down might actually be working it is just running at the same time as front/ back so you did not realize it. Run it up and down a few times and see if it is moving at all. The large nut at the front of the worm gear does not adjust the seat, it is simply a stop so that the worm gear does not travel too far. To manually move the adjustment, you have to spin the adjuster where the cable goes in. That adjuster basically has a nut inside that spins around the large worm gear to move the seat up/down. It is possible that this went bad, but I don't think I have ever seen a bad one. You will need to take the transmission apart to clean and lube it properly. Once you have it off the seat, there are 2 or 3 Philips screws that hold the two halves of the case together, The gears inside of this are what are likely sticking. Shimming the front of the seat may work, but it is more likely to raise the seat even higher into the roof giving you even less head room.
Ok, so I tried what you suggested about trying the up/down from the midpoint front/back, and no up/ down movement. I plan on ripping back into it, but prob not for at least a week or two. For now I just wanna figure out a temporary fix to get my butt lower 😀
Also, when I take the transmission apart, are there any parts/pieces that will come "flying" out that I would be in danger of losing?
When you take the trans apart, there are not any parts that will come flying out, but there are some small washers and springs, so it would be best to take it apart over a clean area or work bench. Once you get it apart, you will see it is not real complicated inside so you should not have much trouble. The old grease can get pretty hard. I usually use lacquer thinner to get it off. The larger plastic gears are nylon. I have used lacquer thinner on a rag to wipe them off, but I would not recommend letting them sit in thinner. I can help more with other issues and diagnosis once you get it apart. As for the different bases, The one with three cables is a later design. It has a bigger bench seat motor and dual drive cables to help move the seat better. I am a little surprised that your car does not have this style, because I thought they came out in 72. They are said to be more rare. Both styles will work fine though. I have used both and I can't say that there is a noticeable difference between the two. If the problem on your seat is with the actuator it may be difficult to get apart because they can be a bit of a pain to get out when they are working. Once you get the seat track out again post some pics and I will try to help you figure out the issue.
When you take the trans apart, there are not any parts that will come flying out, but there are some small washers and springs, so it would be best to take it apart over a clean area or work bench. Once you get it apart, you will see it is not real complicated inside so you should not have much trouble. The old grease can get pretty hard. I usually use lacquer thinner to get it off. The larger plastic gears are nylon. I have used lacquer thinner on a rag to wipe them off, but I would not recommend letting them sit in thinner. I can help more with other issues and diagnosis once you get it apart. As for the different bases, The one with three cables is a later design. It has a bigger bench seat motor and dual drive cables to help move the seat better. I am a little surprised that your car does not have this style, because I thought they came out in 72. They are said to be more rare. Both styles will work fine though. I have used both and I can't say that there is a noticeable difference between the two. If the problem on your seat is with the actuator it may be difficult to get apart because they can be a bit of a pain to get out when they are working. Once you get the seat track out again post some pics and I will try to help you figure out the issue.
Sounds good...and mine does have the three cables 😀
Before you do anything else, go back out and try the up/down movement again. First, move the front/back adjustment so that the seat is in about the middle of its range. Then run the up/down adjustment. If the front/ back movement is sticking in the transmission, the up/down might actually be working it is just running at the same time as front/ back so you did not realize it. Run it up and down a few times and see if it is moving at all. The large nut at the front of the worm gear does not adjust the seat, it is simply a stop so that the worm gear does not travel too far. To manually move the adjustment, you have to spin the adjuster where the cable goes in. That adjuster basically has a nut inside that spins around the large worm gear to move the seat up/down. It is possible that this went bad, but I don't think I have ever seen a bad one. You will need to take the transmission apart to clean and lube it properly. Once you have it off the seat, there are 2 or 3 Philips screws that hold the two halves of the case together, The gears inside of this are what are likely sticking. Shimming the front of the seat may work, but it is more likely to raise the seat even higher into the roof giving you even less head room.
Here's another theory...is it possible the end of the up/down cable is worn enough that it won't engage the adjuster?
Take the plastic cover off the front of the mechanism, you will see 2 square head openeings, this where the drive cables attach. One does forward reverse, one does up and down.
You can put a square head bit in a power drill and turn these cables from this spot and manually move the seat.
Far from ideal, but it works, unless something else is jammed. I've had to resort to this before just to be able to reach the bolts to get a seat out of the car.
Take the plastic cover off the front of the mechanism, you will see 2 square head openeings, this where the drive cables attach. One does forward reverse, one does up and down.
You can put a square head bit in a power drill and turn these cables from this spot and manually move the seat.
Far from ideal, but it works, unless something else is jammed. I've had to resort to this before just to be able to reach the bolts to get a seat out of the car.
The cable turns when I operate the switch, so that's not the issue.
