[oldguy668]

The engine won't shut off. Using the Painless harness with a one-wire alternator set up exactly as shown in the Painless instructions. The engine will not shut off with the temporary toggle switch I have, and continues to run with the battery killswitch off. I'm obviously getting current from the alternator backfeeding into the ignition circuit, which I thought was not possible with the one-wire. Any suggestions?

Okay...I found it. I had one relay that was defective and not dropping out when it was supposed to. I have several assorted relays behind the dash for my "keyless" ignition/start system, and the one that was supposed to kill the MSD was hung up.

[ September 14, 2002, 05:33 PM: Message edited by: oldguy668 ]

 

[Michael Everson]

In the painless harness i believe the ignition switch breaks the contact from the alternator, No?
Where is your alternator wire going? Also i have heard of people getting power feedback from the electric fan running just after shut down.
Mike

 

[NAH]

Try removing the wire from the alternator then start an shut off the engine to make sure that is the problem. I ran the Alt wire to the battery side of the starter (no remote solonoid)and it works fine.

 

[oldguy668]

I just installed the mother of all fans. I'm sure if it's spinning at full speed it'll put out enough power to light a small town. If that's the problem, how do I solve it.

 

[Michael Everson]

A one way diode. I think thats the right term.
Mike
BTW are we still on for saturday?

 

[oldguy668]

Yes...I should be there by 10.

 

[Minitruk]

Working on a Triumph TR-6 in the shop one day fresh from the body shop and you can guess what kind of electrical problems they hand you. The ones they've already worked on for a week without asking any help and could not fix(no offense guys not all shops were like the brain surgeons we worked with and they didn't have a forum for help). Cut off the key, take it out, car still ran. Only way it would cut off was if you cut on the interior lights, opened the door(hint interior light came on) or pulled up the hand brake(hint brake light on dash came on)and they thought that would be a problem for the driver of a British car, merely another step in the process. Turned out one of those one-way diodes was letting current pass thru to the ignition unless it was grounded by the burning bulb(found diode inside the wrapped wirining harness under the dash) apparently blew when the were electric welding on some panels and accidentily got into the harness, which they only admitted to later I talked with a buddy in there shop working on a different car at the time. Don't make your buddies mad, they have the most dirt on you. Learning to read wiring diagragms by Lucas prepared you for any other diagragms I've seen since and yes they were my first.

 

[Dior55]

As far as your killswitch not shutting down everything, you must have hooked up the kill switch on the positive side of your battery. If you hook your kill switch to the negative side, you'll kill the ground to the car and she should shut down when you pull the plug.

 

[Robert Duncan]

Dior55,
I don't see how that could make a difference. The alternator has it's own ground. A switch on the battery ground lead would effectivly isolate the battery, but have no affect on the alternator. The alternator field circuit must be disconnected from the positive side of the electrical system to shut it down.

 

[tbarcelo]

Just FYI, "one-way" diode is a bit redundant. Diodes are "one-way" by definition ... they allow current to flow in one direction but not the other (until you reach their reverse breakdown voltage).

-Trevor

 

[mikiec]

The kill switch hooked to either the + or - side of the battery will not kill a running engine when turned off. I tried it both ways.

It has something to do with the alt. Posted before but I do not remember.

mike

 

[mn12]

Correct me if I'm wrong but it would seem cutting power to the positive side of coil would be the way to turn the motor off. In addition I was always tought (perhaps incorrectly) that removing the load from a spinning alt by disconecting the feed wire was a sure fire way to destroy an alt.

 

[oldguy668]

See the edited post at the top.

Thanks