Why two resistors in coil B+?

[OrangPeEL]

Mostly stock '73 1.9L GT... tan top bosch coil. Coil clear resistor wire and black start feed wire still married in original female spade, but instead of attaching to coil B+, there's a ceramic block (another resistor?) in between. I am using a stock condenser. Mounted on LF fender- it show in this pic:
'73 GT engine - Opel Photo Gallery

It has been run like this for at least the last 25years. Never recognized it [ceramic block] as out-of-place; thinking it was "Opel" and supposed to be there.

I've had some ongoing starting and runability idiosyncrasies... hmmmm.

Is that "block" serving any beneficial/intended purpose that the resistor wire doesn't... or is it just making both the start and run circuit of ignition "amp anemic"? Any harm in removing it?

Advance thanks!
-Dan

[wrench459]

ooh weee is this a can of worms
Without knowning how the P/O wired the ignition..
That white block is not a condensor ..its a resistor

[namba209]

A couple of things here. You stated coil B+ in your initial post, and according to my DESTEC schematic, the only B+ connection is on the alternator. If you're referring to the coil + connection then I can tell you the aftermarket ceramic resistor is dropping the voltage to your coil in half, in both start and run cycle, not a good thing. I would remove the wires from the ceramic resistor and splice them together, well insulated, and see if it helps your problem.

[Dale .D]

Originally Posted by OrangPeEL Mostly stock '73 1.9L GT... tan top bosch coil. Coil clear resistor wire and black start feed wire still married in original female spade, but instead of attaching to coil B+, there's a ceramic block (another resistor?) in between. I am using a stock condenser. Mounted on LF fender- it show in this pic: '73 GT engine - Opel Photo Gallery It has been run like this for at least the last 25years. Never recognized it [ceramic block] as out-of-place; thinking it was "Opel" and supposed to be there. I've had some ongoing starting and runability idiosyncrasies... hmmmm. Is that "block" serving any beneficial/intended purpose that the resistor wire doesn't... or is it just making both the start and run circuit of ignition "amp anemic"? Any harm in removing it? Advance thanks! -Dan

I'm very interested in this also.I have the identical set up I think & the starting system is very poor.Any voltage drop at all & it's a bugger to start .Acts as if there's a short or something.In & out of engaging.Replaced the starter & solinoid,no difference. I was told that this resister had to be in because of the pertronix set up.Had the flame thrower & had nothing but problem over heating the resister.Had to change coils & resister size. I know there's a better set up out there but I hate to mess with it since it does work.Please keep this thread going

[kwilford]

The theory and practice of connecting stock and electronic ignition systems has been beaten rather to death in these Forums, but let me take a quick stab (before Otto swoops in with links to the correct way to do it)..

Stock System with Points:

1) Non-resistor coil (typically about 1 ohm across the terminals)
2) NO ballast resistor (which is probably what that ceramic block is you have connected, NOT from the factory!). This can (and must) actually be used ONLY IF the resistor wire has been replaced or bypassed with a non-resistor wire to power the coil
3) Resistor wire (clear insulation, might be yellowed by now, about 8 ohms IIRC) from switched terminal on fuse block to +'ve on coil, gives about 9 volts to the coil when running to help prevent arcing across points and makes coil last longer. Also cuts down maximum voltage to spark plugs (not a "good thing")
4) Black wire also attached to +'ve on coil, comes from inside wiring harness but actually originates from starter solenoid (second terminal on solenoid) to bypass resistor wire to provide a full (non-resistored) 14 volts when the engine is being cranked over
5) green wire from -'ve on coil to points, condenser also attached to points to help prevent arcing, other side of points are grounded to the distributor base plate which in turn MUST be grounded by that little metal braided strap inside the distributor.

OK, now for the

Pertronix (or similar) Ignition

1) Coil can be non-resistor type, but then MUST still be powered by a resistor wire (or ballast resistor). Pertronix instructions clearly state that a 3 ohm coil (Flamethrower has both types) can be used on a 4 cylinder engine WITHOUT a resistor wire or external ballast resistor with the Pertronix Ignitor
2) The Ignitor MUST be powered by a NON-RESISTORED power supply. That is the red wire from the Ignitor in the distributor. So if you use the stock non-resistored (1 ohm) coil, you MUST power the coil with the resistor wire, but the Ignitor itself MUST be powered by a SEPARATE non-resistored wire
3) The black wire from the Ignitor connects to the -'ve terminal on the coil.
4) The stock black wire from the solenoid can be left intact
5) no condenser needed
6) no little metal braided strap needed inside the distributor

I think that about covers it. Let the discussions 'ad nauseum' begin...

[Dale .D]

Originally Posted by kwilford The theory and practice of connecting stock and electronic ignition systems has been beaten rather to death in these Forums, but let me take a quick stab (before Otto swoops in with links to the correct way to do it).. Stock System with Points: 1) Non-resistor coil (typically about 1 ohm across the terminals) 2) NO ballast resistor (which is probably what that ceramic block is you have connected, NOT from the factory!). This can (and must) actually be used ONLY IF the resistor wire has been replaced or bypassed with a non-resistor wire to power the coil 3) Resister wire (clear insulation, might be yellowed by now, about 8 ohms IIRC) from switched terminal on fuse block to +'ve on coil, gives about 9 volts to the coil when running to help prevent arcing across points and makes coil last longer. Also cuts down maximum voltage to spark plugs (not a "good thing") 4) Black wire also attached to +'ve on coil, comes from inside wiring harness but actually originates from starter solenoid (second terminal on solenoid) to bypass resistor wire to provide a full (non-resistored) 14 volts when the engine is being cranked over 5) green wire from -'ve on coil to points, condenser also attached to points to help prevent arcing, other side of points are grounded to the distributor base plate which in turn MUST be grounded by that little metal braided strap inside the distributor. OK, now for the Pertronix (or similar) Ignition 1) Coil can be non-resistor type, but then MUST still be powered by a resistor wire (or ballast resistor). Pertronix instructions clearly state that a 3 ohm coil (Flamethrower has both types) can be used on a 4 cylinder engine WITHOUT a resistor wire or external ballast resistor with the Pertronix Ignitor 2) The Ignitor MUST be powered by a NON-RESISTORED power supply. That is the red wire from the Ignitor in the distributor. So if you use the stock non-resistored (1 ohm) coil, you MUST power the coil with the resistor wire, but the Ignitor itself MUST be powered by a SEPARATE non-resistored wire 3) The black wire from the Ignitor connects to the -'ve terminal on the coil. 4) The stock black wire from the solenoid can be left intact 5) no condenser needed 6) no little metal braided strap needed inside the distributor I think that about covers it. Let the discussions ad nauseum begin...

Hi keith. Hate flogging a dead horse but giving the previous info I gave you & inputting that, at the moment, my ignition is inoperative so I have to turn the key on & push a switch that the dealer installed. Is the push button start wired properly? Just asking for an educated guess. I know that there's a lot of experts out there that'll just be shaking their heads at my lack of knowledge but eh that's life. PS. saw your weather out there yesterday . Nuts!

[OrangPeEL]

Ron & Keith-

Posted.
Went to dinner.
Returned & checked gt.com replies.
Eliminated the extra resistor.
Drove GT and for the first time ever it started & ran like a normal car!!

Thanks guys!
-Dan

[kwilford]

Originally Posted by Dale .D Hi keith. Hate flogging a dead horse but giving the previous info I gave you & inputting that at the moment my ignition is inoperative so I have to turn the key on & push a switch that the dealer installed.Is the push button start wired properly?Just asking for an educated guess.I know that there's allot of experts out there That'll just be shaking there heads at my lack of knowledge but eh that's life.PS.saw your weather out there yesterday . Nuts!

Flogging dead horses is considered bad form here in Cowtown...

Anyway, yes, the weather yesterday SUCKED here in Calgary. At 0630 hrs, I noticed a light flurry as I read the morning paper while eating my HN Cheerios, with nary a word in the forecast about snow. Not that a flurry is unheard of in the Rocky Mountain Foothills in April. By 0730 hrs, when my wife returned from running with the dog, there was a good three inches on the ground. As I turned out of the driveway at 0755, the snow that I had just swept from the car was reappearing almost as fast. Two and a half hours later, in what is normally a twenty minute commute, I parked my car at work with ANOTHER 5 inches on snow that had accumulated on it during the lengthy pauses on Crowchild Trail, normally a 90 km/hr speedway. Snow continued on and off throughout the day, causing me to reflect on that job offer in Melbourne Australia, while accumulating a full eight inches of white cement on the heretofore almost green grass....

Anyway, I digress. If the push button starter does what I suspect it does and energizes the stock Opel solenoid (perhaps via a relay a la an "Otto Start"), and if the bypass coil wire is still intact and connected properly, the coil sees a full 14 volts during cranking. What happens during running is hard to guess, but if you have a ballast resistor wired into the circuit, I would presume it cuts the coil voltage down to 9 volts. HOWEVER, if the ballast resistor is supplied by a RESISTOR WIRE, then you have twice the required resistance during "run" mode, and your spark is commensurately reduced in voltage. But truly impossible to say without seeing the wiring and applying a voltage meter to the relevant points.

[Dale .D]

Originally Posted by kwilford Flogging dead horses is considered bad form here in Cowtown... Anyway, yes, the weather yesterday SUCKED here in Calgary. At 0630 hrs, I noticed a light flurry as I read the morning paper while eating my HN Cheerios, with nary a word in the forecast about snow. Not that a flurry is unheard of in the Rocky Mountain Foothills in April. By 0730 hrs, when my wife returned from running with the dog, there was a good three inches on the ground. As I turned out of the driveway at 0755, the snow that I had just swept from the car was reappearing almost as fast. Two and a half hours later, in what is normally a twenty minute commute, I parked my car at work with ANOTHER 5 inches on snow that had accumulated on it during the lengthy pauses on Crowchild Trail, normally a 90 km/hr speedway. Snow continued on and off throughout the day, causing me to reflect on that job offer in Melbourne Australia, while accumulating a full eight inches of white cement on the heretofore almost green grass.... Anyway, I digress. If the push button starter does what I suspect it does and energizes the stock Opel solenoid (perhaps via a relay a la an "Otto Start"), and if the bypass coil wire is still intact and connected properly, the coil sees a full 14 volts during cranking. What happens during running is hard to guess, but if you have a ballast resistor wired into the circuit, I would presume it cuts the coil voltage down to 9 volts. HOWEVER, if the ballast resistor is supplied by a RESISTOR WIRE, then you have twice the required resistance during "run" mode, and your spark is commensurately reduced in voltage. But truly impossible to say without seeing the wiring and applying a voltage meter to the relevant points.

Thanks again keith.You may of nailed it on the head.Next time in the shop I'll get them to check that.I have a different relay at the moment wired in for the ignition but I do have a otto start as well.I'll put the otto start in once I get the ignition switch repaired. I lived in calgary during the 80s.Left just after the olympics.Really liked the sun in the winter there but to darn cold & winters to long and as well I wasn't much of a city boy.Now I'm in a small town just above Victoria.Only thing that sucks here is the rain.Like anything you get used to it.Half as much as vancouver though.Take care