Packard Forum Index » V-8 (1955-56)

BTW. if the TL motor is removed then don't let the armature fall out of it. IIRC the armature is not held into the motor housing so it can fall out once the motor is removed.

bhappy,

Sorry to read about your TL problems. Have seen it happen in 2 56 Clippers in Packards North Texas region.

I have had issues on a 55 Patrician, one of the bolts sheared off on an upper "A" arm. Another time the same car, the TL motor would engage, but no leveling. Turned out the outer gear would spin, the middle part of the case, so no movement of the arms.

My suggestion is to put a car ramp under each wheel to simulate the car "level", but up in the air. A poor man's lift. I would also have jack stands under the frame for extra safety. (belt & suspenders) My understanding is that when the car is level the TL leveling system is at "rest". The compensator bars(short bars)do not have any load. The long bars still have toque, they just do not have to level the car.

I did exactly as been proposed in earlier posts. I removed the leveling motor. However, when I pulled the motor, the case came off and the armature stayed. I just spun the armature by hand, and watched the short bars move. YES it took longer, but it worked.

The big issue is if the gear box is able to rotate the short bars back to the "rest" position.

Once you get the mechanical back to normal, then fix the electrical back to working order.

Thanks for the encouragement and I will continue to right my TL system, but I must leave for CA, my mom is in the hospital. I'll be back in CO 05 June.

I have added the limit switches to this play-by-play of the T-L system's electrics.

One thing that is good to know when working on returning the vehicle to stock: The timing box on the frame sends out a ground to the solenoids when activated. The pull-in coil of the solenoids are internally connected to "hot" (+ 12VDC) via the bus bar "feed" side terminal and wants a ground to complete the circuit and make the motor turn. Current to feed the logic circuit flows through the brake light switch until you step on the brakes, the power comes off of the TL circuit and goes on the brake light circuit. There is a spring loaded switch connected to the torsion bars that senses either up or down, when the vehicle's position changes due to loading or unloading the appropriate switch will close, that sends current through one of two thermal coils wrapped around another contact. The wire wrapped around the "leg" of this switch heats up, which slowly causes the leaf it is mounted on to bend, after 5-8 seconds the end of that leaf closes another switch, which closes the relay for that direction's travel inside the box, as long as the system is at a "normal" center of travel the normally closed limit switches allow the control box to sends a ground to the corresponding solenoid. If the gearbox has traveled to either extreme of its design limit the switch will open the circuit to the solenoid and prevent operation in that direction only.

There--that is a complete description of how the T-L system logic works. Any test light jockey that can do some deductive reasoning can figure it out from here.
Go get 'em.

I JUST REMEMBERED SOMETHING!

The center post on the OE solenoids (where the wire from the control box attaches) has a fiber washer that insulates that post from the can it is mounted in. The fiber washer deteriorates, and that causes the screw post to ground itself, which causes the solenoid to pull in (operate). I replaced my solenoids because of this problem. This would cause the system to work until it couldn't, meaning it goes all the way in one direction then starts blowing fuses. Check the center post on both of your solenoids, wiggle the threaded post and see if the fiber insulating washers are shot on yours.

Great tip Mr PB. That would also cause the links to be bent around the shaft and ruin the gear on the link mechanism. The solenoids on my Pat either stayed engaged or became grounded and activated the TL. I was lucky and heard the motor start running. I was able to disconnect the battery before any damage was done. I replaced the solenoids.

Mr. PB

Does your electrical analysis apply only to 56 TL, or does it apply to 55 as well?

That only applies to 1956, 1955 is positive ground, has a different limit switch that is not mounted in the gear box, the solenoids are under the floor of the car near the gear box (a really bad idea) and the timing/control box is different.
The stock of 55 boxes dried up and there is a service counselor that describes how to fit a '56 box with a (short) custom wire harness that would be easy to make today.

The excellent electrical description of operation Mr PB gave is the same in 55 although brake light switch feed and polarity is different. As he mentioned, the big difference is in the physical design and location of components. There is a schematic showing both systems drawn on the same page. You can compare the two for a quick reference and see the similarities and differences. The one thing I will do differently on the 56 schematic is clean up or better label the limit switch drawings and send to Kev. They are normally closed switches but in the sloppy drawing currently on site a space appeared so they look open.packardinfo.com/xoops/html/downloads/wirediagrams/55-56%20TL%20Schem.pdf

Howard asked me to upload this diagram as an update to the previous one.

Attach file:

---

Size: 299.78 KB; Hits: 54