Ignition Switch?

[63BlueMGB]

Hello All,

I am starting to wire my car. I am using the wiring harness from a 1990 Lincoln MK VII (what a nightmare!!!), basically a 302 EFI harness with all the extars. I am using all associated relays and such, I was going to use the original ignition switch from a 63 MGB, However it does not look like it is going to work with the harness because of it only having two positions. Am  I wrong on that? If you had two buy a new switch with 3 positions (OFF, ACC, Start) what would you buy? Is one better than the other and what would work in the orginal MGB ignition position early dash without modifications. Thought, opinions and ideas always appreciated! Thanks in advance1

[Moderator]

On my car, the buss for "accessory" circuits is powered whenever my battery disconnect switch is "on". Another buss of fuses is turned "on" by my ignition switch. (Examples: ECU, fuel pump, starter, etc.) You could use one or more relays to handle the current load. I use a separate momentary-on switch for the starter. Pushbutton starter switches are fashionable, but I prefer a toggle switch with flip-down guard for the WWII airplane look.

[lars49]

Gee Curtis, I didn't know you kissed you accessory circuits ;-)

[63BlueMGB]

While I like the idea of switches, curtis, I am wanting to contain all this with a simple key switch, although I do like the idea for a simple theft deterrent. But Still... Has anybody used any switches that they feel work better than the others, Model# and info greatly appreciated!

[DiDueColpi]

The accessory portion of an ignition switch is simply a convenience feature Nick.
Nothing says that you can't turn it all on at once with a simple single stage keyed switch.
You're going to have to divide the circuits up somewhat with relays. This is to prevent your car from running on until the heater fan slows down, and or your charge light keeps the engine running forever. I would divide it up into three relay drive circuits. One devoted to the fuel and ignition only. The second for things like the wipers and heater etc. The third would be for the entertainment system only. This prevents all the hard to trace backfeed problems that drive most sane people to ramble on to their bartender until 3am. Or is that just me?
Having said all that, I've sourced most of my ign switches lately from the motorcycle world. They are weatherproof, the keys look nice and they are generally chrome for the raccoon in me. They are a two or three stage switch mostly and I use the third stage for headlights.
Cheers
Fred

[63BlueMGB]

Fred did a quick E-bay search for motorcycle ignition switches and there was not much there, where did you source your motorcycle switches from?

In regards to the 3 stage key, that was the plan, I was going to divide my relays up to operate different functions that is way I thought a 3 keyed would be a better option than a on/off switch, with running the ECC module which is going to be driven by a relay and everything else based upon the EFI circuitry and wiring that already exist.

[DiDueColpi]

Jarz is right next door to my business so bike parts are easy.

[63BlueMGB]

Hello again,

I am fairly good with wiring, however wiring this car is kicking my butt and I fell stupid asking some of these questions but I would rather fell stupid than mess things up. I ended up buying a cheap  3 three position stater switch, as per picture. However some of the switch positions are confusing me. What gets hooked up where? It doesnt help that I am trying to wire two harnesses together, but I still would like some switch postion and wiring location if you all can help? The postions are OFF, ACC, START and BATTERY.

My first question is what is the run position, The start position only seems to be momentary and that is what I wired my starter to. What else whould go to this position?

Second, ACC seems like this would got to everything else, Fuse panel, lights, horn, fan, etc.

Third. Battery, which seems obvious and that is what I have wired to my switch now

I still need to wired multiple things like, igniton coil which should go to the run position, but I am an sure.

Any help, drawings or pictures would be greatly appreciated! Thanks again for any responses and help in advance

[danmas]

Nick:

Your switch should have four positions, going clockwise - ACC, OFF, RUN, and START. It may be OFF, ACC, RUN, and START.

You should have four terminals - ACC, RUN, START, and BATT. RUN may be labeled IGN.

BATT is the power into the switch

ACC - is hot when the key is in ACC or in RUN, but not in START.

RUN (IGN) - is hot when the key is in RUN or START, but not in ACC

START - is hot when the key is in START, but not in RUN or ACC.

ACC is usually used to power a radio so you can play it without having the ignition on.

RUN (IGN) powers everything else except the starter.

[63BlueMGB]

Thanks Dan! Your pic with the nuetral safety switch and information has been extremely helpful Thank You!