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HH56 wrote:
With it failing with 3 control switches, does the leveler move in both directions if you use a small jumper wire and manually ground the solenoid wires at the control box? Touching the ground to either double terminal at the outside end on each side will bypass the limit switches and directly command the solenoids. Since you are bypassing the limit switch make sure a bar is not close to or will be driven into the center of the compensator and only touch long enough to see if it moves. If that works then you can be reasonably sure the solenoids and wiring to them is OK and you can concentrate on the limit switch or control box.

If one direction does not move by grounding the double terminal check to see if there is voltage at that same point. The way the solenoids are internally connected, they need a ground supplied by the control switch to work. At the outside double terminals you should be able to measure 12v to ground which is the voltage coming thru the solenoid winding. A solenoid coil could have failed or some have mistakenly tried to use an ordinary starter solenoid in place of the type the TL needs. Some cars have also had solenoids where water has gotten inside and corroded things to the point the plunger could not move.

If all that is good, then back to the command circuits. Control box inner contacts -- even in NOS switches off the shelf -- can oxidize from sitting and not pass enough current to bring the solenoids in. The limit switch plunger can stick keeping the switch open and the wire where it fastens to the terminal on the back of the limit switch can break. This is fairly common on the switch near the driveshaft if the wires are bundled and pulled tight. You can test them by trying the ground again at the single terminal to either side of the center green power wire.

HH56 wrote:
With it failing with 3 control switches, does the leveler move in both directions if you use a small jumper wire and manually ground the solenoid wires at the control box? Touching the ground to either double terminal at the outside end on each side will bypass the limit switches and directly command the solenoids. Since you are bypassing the limit switch make sure a bar is not close to or will be driven into the center of the compensator and only touch long enough to see if it moves. If that works then you can be reasonably sure the solenoids and wiring to them is OK and you can concentrate on the limit switch or control box.

If one direction does not move by grounding the double terminal check to see if there is voltage at that same point. The way the solenoids are internally connected, they need a ground supplied by the control switch to work. At the outside double terminals you should be able to measure 12v to ground which is the voltage coming thru the solenoid winding. A solenoid coil could have failed or some have mistakenly tried to use an ordinary starter solenoid in place of the type the TL needs. Some cars have also had solenoids where water has gotten inside and corroded things to the point the plunger could not move.

If all that is good, then back to the command circuits. Control box inner contacts -- even in NOS switches off the shelf -- can oxidize from sitting and not pass enough current to bring the solenoids in. The limit switch plunger can stick keeping the switch open and the wire where it fastens to the terminal on the back of the limit switch can break. This is fairly common on the switch near the driveshaft if the wires are bundled and pulled tight. You can test them by trying the ground again at the single terminal to either side of the center green power wire.

I have not worked on my 1956 yet but I understand that the boxes were quite different for 1955. Is it possible that one of yours is that type?

HH56 wrote:
Quote:

I have not worked on my 1956 yet but I understand that the boxes were quite different for 1955. Is it possible that one of yours is that type?

The switch operation and except for the bottom terminal area inside the box, are identical. The main difference between 55 and 56 boxes is external. 55 had 3 exposed screw terminals which could corrode when wet so for 56 they changed to bullet type terminals and enclosed them in a weathertight box. They also added two extra double contact tie point terminals in that enclosure to accommodate the change of limit switch type. A service bulletin was issued noting that when 55 switches ran out the 56 switch was to be used and a short pigtail needed to be ordered and spliced to the 55 loom to connect to the different style terminals.

On your boxes, if cleaning the contacts did not work it almost sounds like you would be a candidate for a solid state switch conversion. Since the Pacific Northwest Region no longer lists them on their projects page I don't know if they still handle them or who else might. Believe the work was done on an exchange basis but maybe someone else knows a source.

If not, the conversions seem to be relatively simple. Photos posted seem to show the original relays and bimetal elements were removed and two time delay relays used in place of the original components. I don't have a photo of the solid state box to post but Riki might have posted some on one of his project blogs. Since the conversion is so simple I know he was doing some research on available relays Amazon carries to find some that might work. Don't know if he actually found one or did a conversion yet but maybe if he sees this post he can answer. Amazon does have a pair of 10 second delay cube types that might work but without actually doing a conversion myself I cannot say for sure they would work or fit inside the switch box.

R H wrote:
I have not got to try the timing relays out.
But no reason they would not work.

The circuit board. A model train guy I know can make up a circuit board.

Then gerber file it to a pcb manufacturers..

Pretty cheap..

But also.

Was going to hit up hh56 about how to replace the solenoids with something solidstate.and heavy duty relays

R H wrote:
I.ll have to ask him to .


Its just. 2. Timing circuits..

On the web many diagrams.. Of timing circuits.

Its working in the relays.

With the timing relays. You can get on amazon. They also have adjustable ones but are expensive.

But its the same just figuring out the wiring.

And I was going to put them under the hood.

Just run wires from switch.