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toddgreene
01-19-2008, 05:38 PM
I have a 1987 "carbed" CRX.

I have my alternator wired directly to the hot post of the battery.
I have the hot post of the battery connected to the Master Disconnect.
All charging current should be going to the battery or through the Master.
All power for the fuse box and ignition comes off the "On" side of the Master Disconnect.

Both the fuel pump and ignition coil definitely shut off when the Master is switched "Off".
However, the engine still runs for about 3 seconds after all power is off.

Is this due to energy still in the coil?
Or have I missed something else?

Thanks,

Todd

dickita15
01-19-2008, 06:34 PM
I have always used a 2 poll (four terminal) kill switch. The large positive battery cable is split at goes to the large terminals on the switch, the wire from the alternator to the battery is split and goes to the two small terminals.

tom91ita
01-19-2008, 10:07 PM
fwiw, here are pictures of the affected section of the wiring diagram for my 1st gen crx and where i connected everything to for the typical shut-off switch.

the notations are rather cryptic but i think you should be able to get the gist.

http://www.flickr.com/photos/tom91ita/page16/

the resistor was just wired to the cage where the kill switch was attached.

tom

toddgreene
02-16-2008, 09:08 PM
Back to the beginning...

I have totally disconnected the alternator and the engine still takes about 3 seconds to shut off.

When I kill either the ignition swith or master disconnect, the ignition shuts off, fuel pump shuts off and the tach drops instantly to zero.

However the engine continues until it runs down.

Any ideas?????

Thanks,

Todd

Z3_GoCar
02-16-2008, 09:59 PM
Is there an idle cut-off selenoid on the carburetor? Ususally this is the reason for run-on. As for the master switch. I use a relay, used in alarms and emobilizers, that has a grounding terminal. When power is cut the relay gounds out the ECU power wire. Oh, and I've got a spare relay in my tool box JIC,

James

toddgreene
02-16-2008, 10:44 PM
No high-tech stuff at all...
Carb is a Weber DGV and a stock electronic ignition.

Todd

Z3_GoCar
02-17-2008, 01:21 AM
No high-tech stuff at all...
Carb is a Weber DGV and a stock electronic ignition.

Todd

Even a type 1 (Beetle) VW's solex has an idle cut-off selonoid. That said and realizing that a DGV doesn't have an idle cut-off selonoid, I'd think that your ignition still has some residuel power in it after shut-off. If you have the same four pole switch as I have, mine's from Longacre, there's no grounding in the switch. The switch just disconects the two battery terminals from the two that go on into the motor. You need a way to ground out the ignition wire from the key when you cut the power. That's why I use the relay. Cut the power to the relay grounds out the ignition key wire and the alternator, same thing with turning off the key switch as I have the BCS and key switch wired in series, it takes both the master switch and the key toggle switch on to start. Turn either off and the car goes off instantly. The current has to have a place to go and it sounds like it can only go throuch the ignition system now.

James

toddgreene
02-25-2008, 04:35 PM
Thanks James,

How exactly do you ground or dump that residual power?

Todd

ITC Racer
07-07-2011, 01:31 PM
I need to add the master kill switch on my carbed CRX. I have the six post switch and get that the large lugs go between the pos battery terminal and the starter and power distribution block.

I believe I then need to run the N.O. contacts on the switch in series with the positive ignition coil post to kill ignition when the switch is turned off. Does the ignition switch (stock) just remove power from the coil or does it ground the coil?

Also for the alternator, do I just add a wire from the alternator output post (on the alternator) to the resistor through the master disconnect switch?

Thanks

Flyinglizard
07-08-2011, 09:53 AM
Wire the coil power directly to the master switch, (no toggle).
But the alt power line must go to the "UP ( bat,side) for this to work.
I see that it is this way already.
I often use the second set of post to wire the ground for the fuel pump(Miata FI) This of course wont work for a carbed car. 3 secs is valid shutoff time.
The ignition system must be a flying magnet( square wave) style and generate a little voltage.