roadside kill switch install help??

[}{arlequin]

ok guys. i'm in a bit of a bind. leaving shortly for vir but don't have the kill switch installed. i have a 6 pole version and sometime before tomorrow's tech, it needs to be in and work.

this is the diagram that came w/ it.




what i'd like to know is how many electrical parts i'm going to need to pick up on the way. spades, terminals etc., as well as which wires are which.

anybody with a longhood car, try to steer me in the general area of what wires i'm looking for. how to find them? how to make sure it's the right one after i find it? etc.

any leads are appreciated.

thanks.

[304065]

Hi Dave.

First question: what are you going to mount the switch to? Weltmeister makes an overpriced piece of aluminum that mounts to the fender bolts on the port side of the car up above the battery. The switch goes through the hole in the aluminum. You MUST mount the switch in a rigid position somewhere. Most people, myself included, mount it near the battery to minimize extra cable runs. Some have actually mounted the switch in the cowl itself, but that requires drilling a hole. The preferred way is to mount it near the battery and remotely operate it with a cable with a loop on the end, and to leave the loop protruding from the corner of the hood with the electrical sticker. That way, when the event is over, you can flip it back inside. I actually mounted a T-handle switch through the drivers side windshield squirter, and ran the cable down to the switch. I also have a second cable running to the dash.

Now, about the switch. The big poles are obviously for the battery. You will need the following:

Ring cable end for the stock battery cable. Stock cables are terminated with a bolt-on clamp. You will need to solder or crimp a cable end that is large enough to accomodate the factory cable, on to the end. You may need to ream out the hole in the end to make it fit on the large pole.

Short positive cable with ring end on one and battery clamp on the other. your FLAPS should have a red-colored positive cable that will be long enough to fit. The ring goes on the switch, the clamp goes on the battery. Use rubber insulators to protect the cables, available at the FLAPS.

Now, for the other connections. You must interrupt power to the ignition. You need a piece of 14 or 16 gauge wire, red in color that will be installed in place of the wire that goes from your fuse box to the ignition. Cut a piece long enough to go from the fuse box to the switch and tin one end of it with a soldering iron. The tinned end goes in the fuse box where your ignition wire formerly was. You unscrew the set screw, remove the wire and replace it with the new wire. On the other end of your new wire, crimp a 1/4" faston connector and insulate it with a piece of heat-shrink tubing or electrical tape. That goes on one of the male faston terminals on the NORMALLY CLOSED contacts of the switch. From the other terminal, you run another piece of wire, terminated the same way, but this time you splice it to the wire to the ignition you removed from the fuse box. Finally, for the NORMALLY OPEN terminals on the switch, you need two wires: one from the battery cable lug on the side that runs to the starter (very important) to one pole of the NO terminals, and the other from the NO terminal to the resistor, and then the resistor to ground. When you throw the switch, the battery current is interrupted, the ignition is cut, and the engine-side battery cable is shunted to ground through the resistor. This keeps the alternator from frying by trying to charge when no battery is present. If you don't hook it up llike that and go to test the switch, the alternator will fry itself.

For the resistor I soldered some 14 gauge wire to the leads, attached a large-diameter ring terminal on one end and a faston on the other, and encased the whole thing in heat-shrink with the leads protruding. That will keep the fragile leads from snapping off the big ceramic resistor.

So, that means you need some wire, heat-shrink tubing that will fit over the fastons, half a dozen 1/4" faston connectors, a crimper, a length of battery cable or a prefab cable, a crimp or solder-on ring battery terminal, and a couple of rubber boots to protect the battery cables on the switch. All FLAPS items.

The wire to the CDI unit is found on the hot side of fuse #8 in fuse box 1 for your '73. You should see some green wires on the body side for the brake lights, etc. Disconnect the red wire on the other side, that's the wire to the ignition.

Good luck! You need about 3 hours to do it right. Be VERY careful working with the battery cables, you could easily fry yourself or burn the car to the ground! WATCH OUT for the positive terminal, I welded my stainless steel watch to it one day!

[}{arlequin]

thank you. that's as good of an explanation as i could have hoped to receive.

[304065]

Dave, I have been there so many times. Always a thrash at the last minute. Be safe and have fun!

[donporfi]

John:
I am impressed with your very accurate installation instructions.
Thanks for posting.

[}{arlequin]

one more question... to prevent various bling from being welded to the positive/battery what do i do to avoid it?

i still have two batteries, so if i disconnect both grounds, am i going to be safe? now i'm even afraid to touch the positive post, meanwhile i have to remove, or at least loosen, it.

i ran out to the store and picked up what i need and probably a lot more of what i don't, but i hope i can return this stuff

again, thanks a bunch john. i feel like i can't screw it up just going line-by-line of your writeup. it's a bit confidence boosting too

if i only had a garage i might be able to avoid these last minute scrambles.

[Series900]

both grounds or both positives detached on a twin batt setup, for "a no welding" during your install, Gr8 write up John, jealous of a VIR getaway Dave, have a great time.

[real550A]

A good "rule of thumb" is to disconnect all battery GROUNDS when doing any electrical work. Also, wise for vehicle storage and battery charging.

[Wil Ferch]

Note also that the original instructions ( talking about Lorries, and such...trucks for us Americans)...shows a particularly DANGEROUS diagram.....POSITIVE post GROUNDS.....

..maybe for the goofy Brits that use positive grounds ( "earth")....but the rest of the world uses NEGATIVE grounds....so simply REVERSE the original ( helpful ?) flyer !!!!

- Wil

[Par911]

Just buy the damn switch Dave.
Good luck this weekend brother, kick some 944 arse.

[kepa75]

Hi,

I have a 2,4S from '72 and I'm trying to install the same switch. Is it right if I connect the cable that goes from the switch over the resistor onto ground (earth) to the same ground where my battery "-" is grounded.
It might be a stupid question, but I really have NO experience with electrics.

Thanks and greetings from Italy,

Peter