Hi again.
I am replacing a non-original washer tank (pump attached outside) with a smaller ditto because of space restrictions due to an alternator conversion. The original wiring loom has THREE terminals; black=earth/ground, darkgreen, and lightgreen/blackstripe. This obviously make sense since the original Lucas washer bottle indeed had 3 terminals. My old washer tank`s pump only has TWO terminals; the darkgreen wire connected to the +pole. and the lightgreen/blackstripe connected to the -pole. The black wire is not connected. The new tank/pump also has two (unlabeled) terminals, one vertical, the other horizontal. The included two-way connector/loom indicates that the red wire is connected to +, black wire to -.
Should I connect both green wires to the new tank/pump and leave it ungrounded like the last one? What is the voltage difference between the darkgreen and the lightgreen/blackstripe wires?

 

the original "Screen Jet" 2-SJ had three terminals, one of the wires was for a 3-second automatic spurt of water, when you flicked the washer switch. Of course people did not flick the switch and instead held it down and burned the pump.

so Jaguar went to the two terminal 5-SJ pump, no automatic spurt. One wire remains disconnected.

Just test the pump leaving one wire disconnected, if I remember correctly, it is the green-striped wire but don't hold me to that, it's been a long while since I installed a universal pump which works fine.

 

Thanks a lot, Jose.
I have attached a picture of the new bottle/pump.
According to the Lucas wiring code by Marcel Chichak:

-Black: earth (ground) connections.
-Green: feeds to auxiliary devices controlled by the ignition switch,
eg. wipers, flashers, etc.
-Light Green/Black Screen: jet switch to screen jet motor.

I will precheck the wiring/color connected to the washer switch on the dash panel before connecting the first pair of wires to the pump`s two terminals. It makes sense that minus/black on the pump should be connected to the common ground system, i.e. the black wire? The most important issue is to avoid any short circuits :-)

 

you're welcome.
yes, that's a good idea to look at the wire connections at the back of the dash switch, misconnecting any wire might just result in a blown fuse.

Black = Ground
Light Green/Black = Hot (test with ohmmeter and engine running)

I used the original glass container, and mounted the new pump near it.

 

Thanks Jose, you are right :-)
The non-latching washer switch is connected to the black and lightgreen/black wires in the dash, and the meter indicates connection when the switch is activated/held upwards. To be 100% sure I will test the voltage between these two wires in the engine compartment when operating the switch with the engine running, I guess it is supposed to measure 12 Volts?

 

I think 12 volts or better with engine running/idling. It really does not matter as long as you have voltage to the green or green/black wires.

Try grounding the black wire by pressing the terminal against any bolt/screw near the washer, then check for voltage at the other two wires.

 

here's wiring diagrams for Lucas 2-SJ Screenjet

 

Was the fix to connect the light green/black wire to position and the black wire to negative? And the switch worked

 

as long as the switch is non-latching, spring-operated, Black wire is Ground, Green with Black stripe is positive/hot/12 volts. But so is the solid Green wire. So you can use either green wire, whichever activates the pump.

 

if it’s spring loaded what’s the position? Do I need to change the switch?

 

Not sure if my reply came through. If my switch is spring loaded go I need to change it?

 

If it's spring loaded, that's the correct one and it should be in the down position for "OFF".
As with all switches, it's either off or on that makes or breaks the circuit.
The switch can be on the 12 volt side or the ground side, it doesn't matter.

 

like JeffR says, it needs to be a switch that returns to OFF by itself, (spring loaded).
also known as Momentary switch.

 

thanks everyone for your help. My car is negative earth so I’m going to connect to the motor the light green/black wire to the positive side of the motor and the black wire to the negative. The green wire will not be connected. The switch I presume I should not have to touch.? In theory if I have understood the threads above it should work. Wish me luck. Apologies but I’m new at this and really don’t fully understand the wiring in the jag

 

the beauty of these cars is their simple wiring. None of that digital module stuff with transistors and chips.

In my 1965 S type, I left the original 2SJ pump in place but installed a modern 2-wire washer pump from a 1985 Jaguar XJ-6. The water hoses were rerouted, one to the glass container, (supply), and one to the wiper washers, (output). Very simple mod, didn't even mess with the switch.