A518 wiring set-up

[ff6849]

I want to wire up an A518 transmission with a switch that I can shut off the OD , and wire in two dash lights that will indicate when the OD and Lock-up Torque kick in and out  will this  set-up work.

[Chryco Psycho]

my concern is all the load for the solenoids passes through the light you want the full power to go to the solenoid directly so the resistance of the bulb doesn't drop the voltage & affect the operation of the OD & Lock up solenoids .
There is a simple way to do this , ............. , can you run the light off the ground side after the solenoid using a seperate ground from the light ?
 Can't seem to draw in your picture 

[ff6849]

could I use a rely with a separate power supply and use the vacuum switch to open and the close the rely to power the transmission solenoids, so the vacuum switch would only power the rely and indicating lights

[Chryco Psycho]

that should work better

[PlumCraZRT]

I think this is maybe what Chryco was getting at... I think this may work better.

[ff6849]

from what I understand the pressure switches create the ground for the solenoid will i be able to run power through it and still use it for a ground   

[Chryco Psycho]

Exactly Plum 
the power once it goes through the resistance of the pressure switch or solinoid has to go to ground to operate .
 What is the 3 pole unit at the bottom with both power & ground connected to it ?

[rockymopar]

The one recommendation that I will make is to use a micro switch on the linkage of the carb  instead of the vacuum switch. My car tends to hunt between OD and third at about 55-60mph. A slight hill would make the vacuum drop, and downshift, then the downshift would create more vacuum, causing an upshift, then the vacuum would drop causing a downshift, and over and over...  A switch on the linkage would be the better way to go, just my opinion.

[ff6849]

the 3 pole unit is the 3 prong transmission plug,

the drawing is from PATC

[PlumCraZRT]

could I use a rely with a separate power supply and use the vacuum switch to open and the close the rely to power the transmission solenoids, so the vacuum switch would only power the rely and indicating lights

I think I understand this a bit better.

Your diagram shows two connectors, on the pressure switches but they each actually have a single node (with two physical attaching locations).   If you try to wire a light between the feed and the OD or TCC terminals, I believe you will be supplying 12V to a (lower?) voltage source, which is a big no-no.

If you wanted to create those indicator lights, I think you would have to use a 4-prong relay for each circuit to supply its respective light.  I can draw a diagram later if you would like... my other concern is that I do not know how much voltage/current is created when the pressure switches close and I've never spec'd a relay before (so I certainly can't provide part numbers).

[ff6849]

Ok I am still a little confused on how the pressure switch actually works when the switch opens does it provide power to operate the OD and TCC solenoids or does it create a ground to operate the solenoids. I am under the impression that the pressure switch creates the ground 

What I would like to achieve is that when the OD kicks in a small indicating light would come on and when the lock-up TCC kicks another light would come on, and  shut off when they kick out. I though that this would be cool to help dial the shift points and way to monitor system, plus I thought that it has a cool factor too   

[PlumCraZRT]

Ok I am still a little confused on how the pressure switch actually works when the switch opens does it provide power to operate the OD and TCC solenoids or does it create a ground to operate the solenoids. I am under the impression that the pressure switch creates the ground 

What I would like to achieve is that when the OD kicks in a small indicating light would come on and when the lock-up TCC kicks another light would come on, and  shut off when they kick out. I though that this would be cool to help dial the shift points and way to monitor system, plus I thought that it has a cool factor too   

So my understanding is that when the proper pressure (or vacuum) is reached, the switches short.  As such, the two pressure switches (OD & TCC) short a feed to ground.  4-prong relays would provide voltage to indicator lights without affecting the OD-to-ground or TCC-to-ground circuits.  You could also route a vacuum switch indicator light (as shown in my diagram) without much effort if you desired.

This is all under the premise that the OD and TCC prongs are actually feeds at the transmission 3-prong plug.

[ff6849]

Thanks Plum that drawing makes sense to me, I really struggle with electrical stuff, I guess I am not wired for it.....

[Katfish]

Following along, would love to see the final install