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not a question of whether the car will run - it will run with or without a battery, it is a question of whether it will start (or even power accessories with the power on)
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not a question of whether the car will run - it will run with or without a battery, it is a question of whether it will start (or even power accessories with the power on)
Gliderman8
Great Pumpkin
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Here’s a video I just made. Positive lead from meter to positive post on battery. Negative lead from meter to negative lead on battery after switch. Turning knob clockwise the meter shows 12+ volts.
Turning knob counterclockwise meter drops to 0 volts.
Turn your knob counterclockwise and try and start your car.
Turning knob counterclockwise meter drops to 0 volts.
Turn your knob counterclockwise and try and start your car.
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The engine probably continues to run because electric power is supplied by the generator or alternator. Turn the engine off, turn the green disconnect off and see if the engine will start.
The engine stops dead when the knob is removed completely and the connection broken. This car has Bosch fuel injection & electric fuel pump. The TR6 will continue to run with battery disconnected. I'll do the meter test and try to start it with knob turned a couple of turns.
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I too have the green knob gizmo on the Alfa and the MG. They work fine. Unscrew the knob a turn or two and the power is disconnected. An engine (as JP and JohnT replied) will run for a time with battery disconnected, that's not a valid test to check whether the green knob cuts power. Put a meter on it to check.
Gliderman8
Great Pumpkin
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Sounds like your switch is FUBAR. Loosening the the knob should disconnect the battery. See the video I posted above. Replace the switch.
Maybe I'm stupid, but if the green knob bolt is in any way touching the bottom plate attached to the post, it will complete the circuit. Only way to break the connection is to completely screw out the knob and remove, thus separating the two plates. Backing it out a turn or two still leaves it attached to the bottom plate. Unless this unit is defective somehow. Are the two plates supposed to fit together tightly? The green knob does have a flat metal part on the bottom. I'll try to attach a picture.
Gliderman8
Great Pumpkin
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They way the switch works is that the screw goes into the bottom plate and when tighten down the bottom hexagonal base of the screw makes contact with the top plate completing the connection.
When the screw is loosened, the hexagonal part of the screw (under the green knob) is no longer in contact with the top plate and the connection is lost.
The plastic insulator keeps the screw "centered" in the plastic so it never comes into contact with the top plate until the green knob is tightened down and the hexagonal top of the screw makes contact.
When the screw is loosened, the hexagonal part of the screw (under the green knob) is no longer in contact with the top plate and the connection is lost.
The plastic insulator keeps the screw "centered" in the plastic so it never comes into contact with the top plate until the green knob is tightened down and the hexagonal top of the screw makes contact.
Gliderman8
Great Pumpkin
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What he said!
Obviously, the part of the plastic insert that the knob fits into is not doing its job of insulating the two plates so that backing out the knob does no good. Somewhere, its still touching metal. I'm just stubborn enough to keep trying to make the thing work before I'll admit defeat and spend Six Bucks for a new one. Definition of Insanity - doing the same thing over and over again and hoping for a different result. Thanks for the advice.
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The metal part of the green knob is making contact where that burned spot is on its hex corner. It looks like the green plastic ring around the hex portion should be raised above the metal and squish down when tightened, and keep the metal hex away from the top plate when loosened.
OK. This (I hope) will be the last post on the Green Thing. I FINALLY got the SOB to work! Doc was right as usual. I reversed the plastic insert, thus holding off the bolt. But it looks like...S&%$ so I bit the bullet and for $7.43 - including tax - at Auto Zone, I got a new Green Thing, tried it out and.....it worked, but it still shows .66 volts even when backed off. This thing will not give me complete 100% satisfaction. Why would it show current even when backed out? I'm glad I don't have to do this for a living.
vette
Darth Vader
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pd, I feel your pain but I think your heart is doing just fine. I mean you passed the stress test. To get rid of the green thingy and install a "REAL" disconnect switch requires you to make up a heavy gauge battery cable from either post (i recommend the one that is grounded) to the switch which would be mounted on the firewall, or in the trunk or anywhere else you want it. I also recommend that the disconnect switch be mounted very near the battery. If you install this switch in the grounded side of the battery then after you make up the heavy cable and attach it between the battery and the switch then you would make up another heavy cable and attach it between the switch and the frame. Of coarse this is a PITA so that is why God made the green thingy. Now if you want to see if your battery really has a drain on it, then some morning when all is quiet and ambient lighting is at a minimum then, after leaving the green thingy completely disconnected (separated) all night, then just touch the grounded battery cable to its associated battery post and take it away to see if there is a spark. A spark mean something is drawing current and no spark means no draw. I'm glad to see your heart is doing just fine. 
TR3driver
Great Pumpkin - R.I.P
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The 0.66 may be coming from something else, like the radio. It probably has capacitors in it to smooth the power from the battery/generator and they will feed back into the line for awhile. 0.6 is generally too low for a solid state circuit (like the radio) to draw power, so it takes a long time for them to run completely flat.
BTW, its generally considered poor practice to disconnect the battery from a running engine. If the alternator or generator happens to be working at the time, the voltage may spike high enough to damage something. And if the regulator shorts, it could go high enough to damage you!
BTW, its generally considered poor practice to disconnect the battery from a running engine. If the alternator or generator happens to be working at the time, the voltage may spike high enough to damage something. And if the regulator shorts, it could go high enough to damage you!
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