Ignition resistor

[Pam's buggy]

After a bump up on pilot and main jet the motor is running great.
With the exception of the coil getting very hot.
I tested it and it's a 6 volt coil with 1.5 ohms resistance. It's a 12 volt battery in it.
I'm going to get a 3.0 ohm resistor to put in it
That should put me at 4.5 total.

The switch doesn't have a post for ballast bypass for start up.
I'm going to put a relay at the transmission.
The positive lead and trigger for the relay will be
Tied to the starter solinoid trigger wire.
The ground will go to the ground strap on the transmission .
Then the bypass wire will go to the coil.

If I'm thinking right that wire will only be hot while the starter is cranking .
Then the coil will go back to the feed with the resistor on it.

Does the stock bug switch have a bypass wire post on it?

And what total resistance are you guys using on a points set up.

I'm used to triumphs and Harley's that use 4-5 ohms to keep from frying the points and coil.
I've found that on kicker model with points that they start much easier with a bypass wire.
Since there is no starter relay I just add a picture power button to hold as I kick.

[Dale M.]

Stock bug does not have a resistor bypass, because stock bug does not use resistor at ignition coil...

Would be simpler and cost about the same to put a 12 volt coil on it.... Relay and resister are just extra stuff that is not necessary and just more failure points, and in the end just cost about the same as putting on a proper coil...

Dale
_________________
“Fear The Government That Wants To Take Your Guns" - Thomas Jefferson.

"Kellison Sand Piper Roadster" For Street & Show.
"Joe Pody Sandrover" Buggy with 2180 for Autocross (Sold)
============================================================
All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[Pam's buggy]

That would work if I found at least a four ohm coil to reduce the voltage to the points.
When you look up a coil for the VW ,it has resistor to go with it.

I went to the parts store,and had them get a boche coil. I put my meter on it and it has 1.5 ohms.
The resistor that goes with it is 3.0 .
For a total of 4.5

Anything less than 3 would cook the points.

With the 1.5 coil I have on it the points are already showing that they are heating up.

If only ran the motor on them a few minutes.
And have not left the key on when not running.

Chevy and Ford's run a resistor wire to the coil.
It's tied in the loom.
Dodge and others use a ceramic resistor.


They all use a bypass feed to put full power at start up.

[Dark Earth]

Here's the coil you want ...

12 volts to the (+) side and condenser to the (-) side.

Here's a link with a good write-up ...
http://vwparts.aircooled.net/12V-Bosch-Blue-Coil-with-Mounting-Bracket-00-012-p/00-012us.htm
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My Build: '69 Baja - Dark Earth Version

~I'm almost done. I just lack finishing up.~

[Pam's buggy]

Looks like the coil at the parts store.
Only 1.5 ohms.

[Vanapplebomb]

The 12Volt Wells brand ignition coil at Autozone is a good deal, and has the correct internal resistor.
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1800 Type 4 Berrien 295

http://www.thesamba.com/vw/forum/viewtopic.php?t=487021

[Pam's buggy]

I will go back and look at the canister coils for other vehicles.
Test and see what they have for a reading .
I don't think that mfgrs and consumer know that
You need certain coils for different ignition. They just think lower ohm is hotter

[Wulfthang]

Look around and see if you can find one of the old "points isolator circuits". In a points type ignition system aka a Kettering System, the points turn the coil on and off. Turn it on (points closed) and the coil builds up the magnetic field. Turn it off (Points open) and the field collapses causing a huge spike in the secondary coil. Zap! It sparks. All of the energy going to the coil goes thru the points and it can be several amps. That causes arcing and wear on the point contacts. Even worse, that arcing is a sloppy break that causes the magnetic field to not build up properly for the next cycle.

A "Points Isolator" works differently. The points turn the isolator on and off and the isolator then turns the coil on and off. There's no wear on the points from arcing and the break is a very clean one. That means a hotter spark. The points bounce that always occurs right after the points slam shut has no effect on it because once it senses the first break, it slams the "electronic door" until that cycle is complete. My point contacts always look very clean because they're only passing a few milliamps. The rubbing block will wear out first.

If you're really lucky, you'll find one of the CDI Boosted ones. That's the kind that I have. It's a points isolator but also a CDI unit. I have it triggering a huge Accel Super Coil and it develops a very clean powerful spark.

If you're electronically inclined, you can find one of the old circuit diagrams and build your own. You can also install a bypass circuit so that if the electronics in the unit fail, just switch it over to regular points operation.

[Dark Earth]

[BFB]

i cant say i have ever given that much thought to a coil, sound like your over complicating it. id think a 6v coil would work fine on 12 v as ive used many used coils and never had an issue. ive also run 120 v into a coil to build a jacobs ladder and it hasnt hurt the coil nor heated it up.
i could be wrong on the 6 & 12 but then again if 120 works ....

[Pam's buggy]

I've never heard of the points isolater.
Always used ballast resistor. Either wire or ceramic.
Can't find the wire type at the store anymore.
Ffffff kids that work there have no clue what you are looking for.
Resistor works great.
Low voltage and amps to the points .

The curcit for bypass is easy to do.
Everyone running low resistance coils, and points have to be cooking them.
Been dealing with points since I was a kid.

I've fixed many bikes with (bad coils) when all it was wrong coil.
I put points in Evo Harley's,cause I like them .
People don't like them cause it takes a few minutes to set them.

I've even used point to trigger a hei module and coil. It's a neat trick to do. But something else to go bad. A extra point and condenser in the tool pouch and your good.

So back to my original question............
What ohm coil are you guys using on your VW?


Went back to parts store
Looked at a coil for old Chevy and Ford's with points ignition.
All are 1.5. And all need a resistor to knock the power down to the points.

I wasn't trying to start a huge controversy here .
Just was asking if the how the VW bypassed the resistor for start up .

Gonna find a resistor and wire it in.
Then wire my relay for bypass.

All who think you don't need to put the ohms in the proper range,are right.
You don't need to,it will run without a resistor.
But it will work longer and better done properly.

If your using points and a 1.5 coil go pull the cap off . Rotate the motor to a point where points are closed.
Turn ignition on and use a plastic fork or similar item,and open the points manually.
It will look like a ark welder.
And I better your points are pitted and burnt.

[Wulfthang]

Yeah, isolators aren't around much anymore since points type ignitions systems have fallen pretty much into history. I use one of the CD booster types on my trail rail and have a spare for that one. You're right about points being easier to rig a fix on. I've heard of some amazing fixes, everything from a paperclip to the foil wrapper from a cig pack. Try that with your electronic ignition!

I'm not sure what kind of circuit you're using that requires a relay. Just use your starter solenoid. Wire the coil in with the resistor in series with the Positive lead. The bypass wire goes from the Trigger aka Switch aka Start terminal on the solenoid directly to the positive terminal on the coil. When you're running normally, the coil is powered thru the resistor. When you're starting the engine, the resistor is bypassed and the coil is getting it's power directly from the 12 volt circuit.

[Vanapplebomb]

This is getting way to complicated. Just get the correct coil for a 70’s bug and be done with it.

Bosch, Beru, NGK, or Wells. Hard to go wrong with their coils.
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1800 Type 4 Berrien 295

http://www.thesamba.com/vw/forum/viewtopic.php?t=487021

[Pam's buggy]

[Wulfthang]

You're right! I was thinking of a starter relay for an American truck that has a separate terminal for the ignition coil bypass. Yes, you will need a separate relay! Sorry for almost steering you wrong!

[Pam's buggy]

It's all good .
I knew what I was after. Lol.

Really I was just wondering how VW did it .
Do they do it off a ignition switch post?

And now that points interrupter.

I am wanting to no more about it.
Was it a after market deal.
Or was it common German technology?

Thanks for everyone's input.

I got a 4 pin relay in the tool box .
Will go find a 3 omh resistor and wire it up and soldered.

[Dale M.]

VW just used a 3-4 ohm (or so ) coil, no relay, no bypass, no resistor ...

https://www.thesamba.com/vw/archives/info/wiringt1.php

Dale
_________________
“Fear The Government That Wants To Take Your Guns" - Thomas Jefferson.

"Kellison Sand Piper Roadster" For Street & Show.
"Joe Pody Sandrover" Buggy with 2180 for Autocross (Sold)
============================================================
All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[Wulfthang]

Here's an article that explains the isolator circuit better than I can. I'm pretty sure nobody makes one anymore but the circuit is easy enough to build. I'll look and see if I have a diagram and parts list. The two that I have are identical and look like they may have been built from a kit. The big problem with mine is that the spark that they produce is noisy in the RF bands. It doesn't affect the radio in my own car...not CB, AM or FM but it strongly affects radios in other cars near me in traffic. The FCC would not approve!! Plus, it sets of car alarms in parking lots. It's hard to creep thru a parking lot when the blowing horns seem to follow you!! But it sure does make a seriously strong and clean spark from an old points type system!
http://www.kirkengines.com/downloads/TransistorIgnitionAdvantages.pdf

[Pam's buggy]

I got it wired in.
Works fine and coil doesn't heat up.

I run none suppression plugs and copper core wire's with points on my bikes.
It's funny watching people fiddle with there radios when I pull up beside them.

As a matter of fact I use jap coils on my bikes
Better quality . They have a duel output using copper core wire. They also have a cap that goes over the wire .
The post inside is a screw you twist the wires on to, then slide the cap on and screw it tight.

The plug ends are the same.
They don't come loose.

[dustymojave]

So what points are you using that you seem to have such an issue with running a VW/Bosch 12V coil? And how have you wired the vehicle? You seem to be putting a lot of effort into trying to reinvent the wheel. Its a VW. Not a Harley.
_________________
Richard
Offroading VW based cars since 1965
Tech Inspection 1963 - 2012 SCCA/SCORE/HDRA/MORE/MDR +
Retired from building Bajas, Fiberglass Buggies and Rails in the Mojave Desert. Also Sprints & Midgets, Dry Lakes, Road Race cars. All types New and Vintage
SoCalBajas Member
Kicked Cancer's A$$...1st and 2nd round...Fight ain't over yet.