73 super ignition switch

[tlkolrod]

Hello all, Just checking to see if its a common problem with early super beetles to have ignition switch contact issues or is it just my luck?c Seems like the contacts inside the sw are bad. Sometimes it takes a wiggle to get good contact. If I have to get it out is there any trick to it?
Thx Toby in PA Gettysburg area

[Marc]

Yes, it's a fairly common problem. Either the plastic that supports the contacts cracks, allowing them to become misaligned, or it overheats and melts so they sink in and no longer touch.
Fortunately, the "modular" style switch that debuted in `72 is easier to replace than the older ones where you had to fish the whole wiring pigtail through into the trunk and connect the individual leads there - but it still takes some time.

They changed to using the same part as a Rabbit in mid`74; your `73 uses the 111 905 865K round-bodied one, not the 171 905 865 that has a "D" shaped end. http://www.jbugs.com/product/111905865K.html

This video is the best one I could locate - it's an early `74 which is like your `73. https://youtu.be/GuoWD_46HXw

A nifty feature of the modular ignition switch is that you can confirm the diagnosis before tearing everything apart - just unplug the connector underneath and plug it onto the new part, then use a screwdriver to turn it. If everything works as it should then, you know it'll be worth the time to replace the switch. If not, you'll need to continue searching for the problem and you now own a spare switch - that's a good thing, because it isn't a question of IF it'll eventually go bad, just WHEN.

[tlkolrod]

That was an awesome response. Thank you so much for the detail
Guys like you make life great
THANKS
Toby

[Marc]

Starting with the `71 models, they added an auxiliary set of contacts to the ignition switch (the "X" terminal contacts) which are closed when the ignition's on but open when cranking. The reason was to make the headlamps switch off automatically with the key, and also when cranking to provide maximum voltage for the starter. Then they started adding accessory loads like defroster fans, etc. to the X terminal to take their load off of the primary contacts that supply the coil (Term 15).

There is NO fuse protection anywhere between the ignition switch & the coil, so if someone connects the condenser wire to the wrong terminal, or one of the wires going to the carb or backup light fuseholder should short out, that entire wire gets real hot real fast - if you find that the Term 15 contacts in the switch got hot enough to melt the plastic block they're in, something like that probably happened at one time.

Some folks like to add an inline fuse to the Term 15 circuit right up close to the switch to add protection against this. Nothing wrong with that idea so long as you remember to keep some spares in the glovebox. A 15-16 amp should be adequate.

Another "upgrade" you might consider is the addition of a "booster" (A.K.A. "hard-start") relay back near the battery in the Term 50 circuit for the starter solenoid - that way the "start" contacts of the ignition switch only have to pass the small control current of the relay rather than feed the solenoid directly. The factory never did, in order to save a few bucks, and the system obviously works without one - at least most of the time - but it's a worthwhile modification. Use a 30 or 40 amp relay and ~10GA wires from the battery to it, and from it to the solenoid.

[ainokea]

A hot or hard start relay is a good idea, but if resistance is your problem, or one of your problems, look under your back seat, left side for 10 gauge wire loom. red comes from the front connects to a red with a black stripe wire that goes to starter terminal # 50, your start circuit. Cut out the plastic connector and install a yellow butt connector between the two ends and cover with heat shrink material to seal. Sometimes this simple repair does wonders for old wiring.

[Marc]

It's a good tip to check that inline connection, but in truth it's rarely the source of a problem. If you replace it with a butt-splice you'll no longer be able to inject power there when chasing a no-crank problem, but that's about all it's good for once the car is assembled (older Bugs didn't even have it) - and if you put a relay in the battery area, the connections there would always be available for troubleshooting purposes.
When I put in a relay, I usually just unplug the wire to the solenoid from that inline connection and shorten it to connect to the relay output (Term 87). The remaining wire is typically long enough to reach from the + battery post to the relay input (Term 30) - if not, use 10GA or 8GA. Then, since the stock circuit from the ignition switch no longer needs to handle the solenoid current you may use a smaller (~16GA) wire from that inline connector to the relay control Term 86 and another from Term 85 to ground/negative post.

You can buy a "hard-start relay kit" (Bosch P/N WR1) which includes a nice little socket and wiring pigtail for $25-$30, but all of the wires are ~16GA and the relay may only be rated at 20A - personally I prefer using a discrete relay, the plastic-shelled type that have a mounting tab you can use to screw them to the body (or just Ty-Rap to a battery cable) and they're cheaper too. Here's a 30A:

[ainokea]

Have to disagree on that particular wire connection not being the cause some hard or no start situation and especially later bugs with that setup. During my working years, I found that connection to be one of the reasons for the slow crank no start problem, especially when the engine was hot. In some cases the owner would have bought new starters, batteries, and even generator or alternator. But the problem persisted. Connecting those two wires cured the problem in many instances. Some ignition wiring has a similar # 50 connection under the dash below the switch, reconnecting that wire in the same way should be done at the same time. I had to do this on the 73 t1 I bought in 07, no relay, no problems since then. On my 67, just ran a 10 gauge wire from ign. sw. # 50 to the starter # 50. However, if the ign. sw. is faulty, it's gotta' be replaced, I also like a 10 gauge wire connected to my starters bottom mounting stud from the batteries negative terminal.

[Piledriver]

Re: coil power---
I like to fuse the ign power wire, and only use it to control an engine compartment mounted fused relay that gets direct battery power.
Stock ignition works pretty OK running on full power, but it's not unusual to only have 7-8v through the old wiring.

A similar setup does wonders for headlights, power bypasses the ign switch/light switch and the hi/low beam relay, just use the outputs to control a pair of relays. For extra bright light, run another feed off the battery.

I have an additional fused feed for my AC (the condenser and evap fans draw ~20A collectively) and gas heater.

[ainokea]

In some instances replacing the two wires from ignition switch terminal # 30 to battery positive and terminal # 50 to starter terminal # 50 will cure most hard start problems. Two very overlooked problems with these 40 year old and older cars, is that driving will heat the chassis causing expansion of the ground contact through out the body. That's one cause but not all causes, of a no start when the engine is hot. Waiting 15 or 20 minutes it will start after cooling off and contracting, re-establishing a solid ground, is a dead give away you got a bad ground. Second is the resistance built up in the old wiring and connectors. Power to ignition switch # 30 comes from the light switch to the fuse panel then to ignition switch # 30. Rewiring directly to battery positive eliminates 3 points of resistance and puts a full 12 volts into the ignition switch. Replacing 2 old wires with new 10 gauge wires will in most cases, cure starting problems. I am not contradicting anyone as all I've seen is valid, I'm just saying what works for me.

[Marc]

Not relevant to a `73 but worth mention if someone has a `74 with a no-crank condition. `74s had a seat-belt interlock relay at the fusepanel (it serves other functions as well so it has to stay in place). Due to popular demand NHTSA allowed them to be legally disabled, which only takes unplugging the occupant-sensor wires at the seat. But the solenoid control current still has to pass through contacts inside the relay, and over time they can develop enough resistance to be a problem. I've seen a couple of incidences where a `74 wouldn't crank on a sunny day unless the hood was left open to prevent the relay from heating up
Simple, pragmatic fix is to just snip off the two biggest wires that go to that relay - one's red/white-stripe, the other's white/red-stripe - and butt-splice them together to bypass the relay contacts.
The relay is J34 here. Wires of interest are Term 50 and Term C: http://www.vintagebus.com/wiring/1303_U ... 1973-2.jpg