Packard Forum Index » V-8 (1955-56)

The Tbar itself touching ground won't matter. Electrically it and the box is isolated but if any of the 4 pieces of metal with holes in them touch ground, that would cause a short.

Ok, thank you. I will try to troubleshoot this tomorrow. I wonder if I unhook the compensator box and this still happens if that means there is a short somewhere in the limit switch. I will be back tomorrow.

Thanks again

Any time either the pink or the yellow wire is grounded the unit will operate. There is nothing wrong there.

As a test of your limit switch, ground one of those wires. As the motor drives the gearbox around, poke the "t-bar" on the limit switch in the direction it would go if the arm on the gearbox were to hit it. Watch your fingers!!!! The motor should stop at once. Try it again in the other direction by shorting the other wire. The t-bar is only the actuator lever for what's inside the little box in Howard's photo. It has no direct electrical action

Those limit switches are quite robust and I seldom have trouble with them. My impression is that yours is probably working OK. Chances are your troubles are inside that black control box with the three wires and little lever that is hooked to the torsion bar.

Ross, How would I test that box?

Update, Like Ross suggested I shorted the one side and then pushed the t bar until the motor stopped. This worked the motor stopped. I then dropped the car on the ground and switched the motor on, it turned and level for about 3 seconds or so and shut off. I then tested the power to the solenoids from the starter and there was none. The fuse was blown again. The fuse blows everytime the car levels and shuts off. I know this because it ran for 8-10 sec when I shorted it under the car and the fuse was ok. When leveling on the ground it was no more than 3. second, the fuse was completely black like it exploded on the inside like it was dead shorted and blew, not overheated

So it seams like it dead shorts when the car is level and disengages, where would I start to figure out the dead short? Compensator box?

Just out of curiosity does it matter if the tail lights are hooked up? Mine are not and was curious if this could cause a short?

Thanks
Bill

The tail lights do not have to be hooked up but there does have to be power on the pink wire to the brake light switch so it can power the light green wire to the control switch. Another question that should have been asked earlier is if the car is disassembled. Without weight of bumpers or fenders, the suspension is generally not able to compensate much and goes to limits.

Since it ran for 8 seconds one thing I would do is make sure the lever did not pass center on the compensator so the bars are now trying to drive around farther and running into the mechanism. There is a top view of the system showing the transverse bars in fig 21 in SM suspension section. Make sure your bars are on the sides shown -- passenger to rear of unit, drivers side to front. The bars going past center is a common result when limit switches fail or someone tries to bypass them. Look for anything else that could be putting a strain on the motor & make sure the bar part on the limit switch Tbar that gets touched by the bars is the later version and is slightly over 2" long. Early switches had the bar too short and didn't reliably work in time.

Assuming nothing is mechanically wrong causing a load then the other thing that can cause the fuse to blow is if the motor is being told to try & run both directions at once. This could happen if the control box is bad or if there is a short in the limit switch or the buss bars so it is trying to bring in both solenoids at once. Packard said the current draw on the motor is around 17 amps max but one thing they did for 56 was change the fuse from a 20 amp to a 30 amp. Nothing else was changed operationally so makes one wonder if the 20 amp fuse was marginal.

Out of curiosity, have you verified the wiring is correct per schematic and no one has miswired something.

Ross may have another idea but one way to test the control switch is to disconnect wires except the light green. Turn on the under dash switch and make sure there is power on the wire. NOTE: If you have the 55 switch it will have only 3 screw terminals on the outside . If your car had the 56 retrofit switch installed the 3 wires will be inside the the watertight enclosure as well as two extra double terminals. No extra wires but except for green, those present will be a different color than the schematic.

Disconnect the link coming from the torsion bar at the switch lever. You can now move the lever freely. There should be spring tension felt in both directions from center. Move the lever one direction against the tension and after 6-7 seconds you should hear one of the relays click. Move the lever back to center and somewhere in that travel the relay should drop out. Now move the other direction and after the time delay you should hear the other relay click. If you want you can check with a meter. The two now empty terminals should each short to ground --but only one at a time -- if the relays are working.

This past weekend my TL stopped working, so under the dash I went. All fuses there just fine. With the help if a friend, we went under the car. Found the fuse to the TL motor blown. This is a thirty amp fuse. Replaced fuse and now I'm rebuilding the extra TL motor I had on the shelf. Rebuilder didn't even blink when I placed that unit onto their counter. "Give us a couple of days" is all they said.

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The motors seem to be wonderfully long lived and reliable--I have rarely had to do more than free up the brush holders on them; have yet to see one fried.

Now, the gearbox is another matter. The gears themselves are quite fine and also do not give problems unless they have seen a lot of water somehow. The first reduction in this triple reduction box is a worm drive direct off a fitting on the motor shaft. One end of the worm pilots on the armature, the other end is supported by a small ball bearing. This bearing also takes the thrust of the worm drive in both directions. Because it is at the top of the gearbox, where condensation can occur, this $6 bearing is often in quite bad shape. If the leveler is noisy,this is almost always the cause. Sometimes the c-clip that holds the shaft to the bearing has rusted away or pushed off. This can cause the motor to stall when subjected to load.

How does your leveler sound at the time the fuse blows?

The motor and compensator are good. I am having two problems. First the car is not level so the compensator arm is not right. Second I have a random short somewhere that only shorts when I have the car on the ground and not in the air. Once I fix this short I should be good. I have to go look through the literature for the best way to level the car so I correctly adjust this arm. I think the fuse is blowing because the car is trying to adjust itself and then randomly shorts. I followed hh56 idea on testing the comp box and it tested good.

Thanks guys will update tomorrow.

If you mean the car is not level front to back, then it is just a matter of adjusting the length of the turnbuckle between the bar and controller. If the car is not level side to side we have another topic to start.