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Happy Friday Gents!

car stopped running yesterday. Got it towed back and it looks like I have a coil failure. Currently have a Magnaspark that went bad, a new one will take 3 days or so to get. Curious if getting a different manufactured coil and installing today will effect anything or if I should stick w another Magnaspark?

thank you in advance! Bright side- at least I wasn’t on the highway during failure!

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Yeah mine stopped at a car show. Perfect. Just a small local group of guys. More of a meet and greet. I did the diagnostics and determined it was the module. Although they were backordered, Marieannne at CB Performance sent one out to me at no cost. She and CB are first cabin when it comes to customer service.

Installed and it lasted less than a day. Ordered two more and I will try the next one. If I had installed it wrong, it would have fried and never started.

We will see!

.

FWIW, I just kept using my old Bosch coil when I switched from an imitation 009 to a MagnaSpark II. All has been fine ever since.

The folks at CBP told me you bet, fer sure, you can use a Bosch coil. They just don't make as much profit out of the transaction in that case.

My take has always been that a Volkswagen engine shouldn't need a space-age ignition system to, like, run OK because, well, Volkswagen. And I'm also wondering just how space-age a CB ignition coil could be inside, anyway. I mean, would the electrons really notice a difference?

Coils in general are happier the farther they are from heat and vibration. Mine is mounted in the left, rear corner of the engine bay and not on the shroud. It doesn't look as nifty mounted there as it would on the shroud, but I figure I'm not a stylish guy otherwise, and having my coil on the shroud probably wouldn't help me get invited to the right parties, anyway.

Just saying.

Last edited by Sacto Mitch
@Sacto Mitch posted:

I'm not a stylish guy otherwise, and having my coil on the shroud probably wouldn't help me get invited to the right parties, anyway.

Just saying.

She grew up with the children of the stars
In the Hollywood hills and the boulevard
Her parents threw big parties, everyone was there
They hung out with folks like
Dennis Hopper and Bob Seeger and Sonny and Cher

... and so on, etc...

I told her I ain't so sure about this place
It's hard to play a gig in this town and keep a straight face
Seems like everybody's got a plan
It's kind of like Nashville with a tan

I don't think you're missing much, Mitch.

Hey, @Panhandle Bob!

I'm wondering if your coil is the culprit, because you've gone through 3 modules and still on the same coil?  It may have too low resistance in the primary (12 volt) side, thereby making your electronic module work harder and/or croaking.

I hate to make you buy more stuff just to experiment, but we know from @Chappy that you can run a Bosch Blue Coil on it with success and maybe you have the old one still kicking around the Garaje con su Speedster.....

Food for thought....

Last edited by Gordon Nichols

Define low resistance reading on a multimeter, please.

Depends on what you have. Iirc, resistance of “Bosch Blue” coil is 3-4K on the primary side and 11-13 on the secondary.
My F.A.S.T Ignition specified high or low resistance coils. The Pertronix’ site lists 3: 0.32, 1.5, and 3.0.
It all depends on what your ignition system is made for.

btw: if you’re not familiar, you measure the primary resistance across the two leads +/- or 30/15) and secondary across the + terminal and hot lead.

FWIW: when I chased my tail wrt “carb issues” a couple of years ago, my coil tested fine with a digital multimeter but when I finally broke out my Simpson 260 the secondary was reading 17K ohms. Replaced it and my “carb issues” went away.

Last edited by dlearl476

Define low resistance reading on a multimeter, please.

To answer your question, Bob - the original PerTronix modules wanted to see at least 3 ohms on the primary circuit of the coil (between the two terminals). Less, and the module will burn up. "Hotter" coils from various places have less resistance and will burn them up. Allegedly, you can run anything you want with a PerTronix II, but I don't trust them. I ran a hot coil with a Comp-u-Fire module by using a ballast resistor from my FLAPS (tell 'em it's for a 196X Chevy truck if they ask).

I've got no idea what a CB MagnaSpark points replacement module wants (of if it cares), but it's possible that the latest batch of their very own east Asian sourced coils might not play nicely with their latest batch of east Asian sourced points replacement modules.

This entire thing could probably be avoided by using the MagnaSpark module as a trigger for a CDI box, which are generally fine with whatever stupid-hot coil (or not) you want to throw at it.

It's just a shame nobody makes an ignition worth having at this point. Mallory Uni-Lite used to be the gold standard, and their pickups are dead-nuts reliable, but their advance curves went all to heck about 15 years back. The CB curve is apparently really nice, but they keep failing at a rate that worries me.

my bus stopped dead in it's tracks once due to the points fried....which i found out after buying a new bosch coil...no luck...after a waste of a weekend round trip back home for a trailer...bought a new set of points and VROOM....i also had the loose wire from the coil problem....was smart enough to remedy that....like rosann rosanna dana said "ya know jane, it's always SUMTHIN"...if it's not one thing it's another"....all reasons i FINALLY  escaped the AIRCOOLED world for SUBARU power....haa!...sorry for that...just IMHO

@jncspyder posted:

my bus stopped dead in it's tracks once due to the points fried....which i found out after buying a new bosch coil...no luck...after a waste of a weekend round trip back home for a trailer...bought a new set of points and VROOM....i also had the loose wire from the coil problem....was smart enough to remedy that....like rosann rosanna dana said "ya know jane, it's always SUMTHIN"...if it's not one thing it's another"....all reasons i FINALLY  escaped the AIRCOOLED world for SUBARU power....haa!...sorry for that...just IMHO

And this good sir, is why I decided to put a Suby engine in my current 356 build. One air cooled in the garage is enough to keep me busy it seems.

And it looks like I may be swapping out this Blue coil after all as I’m now getting the old snap crackle pop while shifting in 1st & 2nd. Like Stan mentioned I keep thinking it’s carb related but they are totally dialed in. Sigh.

@Stan Galat posted:

I just looked it up. Primary resistance on the coil supplied in the MagnaSpark kit is 1.1 ohms. Try running your blue coil, Bob - or getting a $10 ballast resistor.

I'd tell you to get a CDI box, but I don't know if you're ready for that kind of awesome.

1.1 ohms? That is too little, that coil will be drawing over 12 amps through that little electronic point eliminator. THAT is the problem for sure that is burning out these modules.

I do believe if higher spec components were used, 15-20 amps through the Magana Spark would be no problem. But hey, lowest cost/highest profit rules.

A different(higher resistance) coil or the addition of a ballast resistor in series with the coil should permanently solve this problem.

Yeah, CDI box would fix it, it has it's own power source and would run all that current through the CDI box rather than the tiny little point eliminator circuit.

@DannyP posted:

1.1 ohms? That is too little, that coil will be drawing over 12 amps through that little electronic point eliminator. THAT is the problem for sure that is burning out these modules.

I do believe if higher spec components were used, 15-20 amps through the Magana Spark would be no problem. But hey, lowest cost/highest profit rules.

A different(higher resistance) coil or the addition of a ballast resistor in series with the coil should permanently solve this problem.

Yeah, CDI box would fix it, it has it's own power source and would run all that current through the CDI box rather than the tiny little point eliminator circuit.

Yep. Once I saw the spec, everything came into focus.

So I replaced the ignition module. I went back to a blue Bosch coil I had on the shelf. Cleaned up all the contacts and double checked all connections everywhere.

Shot in a healthy dose of starter fluid, gave the electric fuel pump a few seconds to get fuel back to the Dells and started cranking.

Took a few seconds and then fired right up and almost immediately settled into idle.

Test drove just fine.

I still don't quite know what the problem was. I'll be carrying a spare coil and module around in my bag though.

I still don't quite know what the problem was. I'll be carrying a spare coil and module around in my bag though.

Sure you do!

@Stan Galat posted:

I've got no idea what a CB MagnaSpark points replacement module wants (or if it cares), but it's possible that the latest batch of their very own east Asian sourced coils might not play nicely with their latest batch of east Asian sourced points replacement modules.

This entire thing could probably be avoided by using the MagnaSpark module as a trigger for a CDI box, which are generally fine with whatever stupid-hot coil (or not) you want to throw at it.

@Stan Galat posted:

I just looked it up. Primary resistance on the coil supplied in the MagnaSpark kit is 1.1 ohms. Try running your blue coil, Bob - or getting a $10 ballast resistor.

I'd tell you to get a CDI box, but I don't know if you're ready for that kind of awesome.

@DannyP posted:

1.1 ohms? That is too little, that coil will be drawing over 12 amps through that little electronic point eliminator. THAT is the problem for sure that is burning out these modules.

A different(higher resistance) coil or the addition of a ballast resistor in series with the coil should permanently solve this problem.

For posterity - apparently, the coil supplied with the Magna-Spark kit is too hot for the pickup module supplied in the distributor.

Run a different coil, or a CDI box, or suffer through the purgatory Bob has endured.

Last edited by Stan Galat

.

@Stan Galat posted:


...For posterity - apparently, the coil supplied with the Magna-Spark kit is too hot for the pickup module supplied in the distributor...

Run a different coil, or a CDI box, or suffer through the purgatory Bob has endured.



Still, you have to wonder how CBP keep selling these and how the coils work OK for a lot of folks.

And why the cheap pickup units in the dizzies (Pertronix, Magnaspark, whatever) also seem to work for some folks while others have repeated failures. Yeah, the quality control is terrible, so one example may be weaker than the next, but why does one guy have to replace three, while others put in one and are good for years?

I keep coming back to the difference in environment from one installation to another — in particular how much heat (and vibration, too) a given installation subjects a coil or dizzy to.

Heat is the biggest enemy of electronic components. The heavy current a 1.1 ohm coil sends through the module in the dizzy in itself  isn't the problem. It's the heat that current creates that melts and fatigues components. Depending on how much power an engine generates, how well the oil is cooled, how much outside air flows through the compartment, and how hot the ambient temps, one engine bay could typically run 30 degrees hotter than another. That could well be the difference between ignition components surviving or failing. One guy concludes these coils are great, another says they're worthless junk.

When we configured my engine, my biggest concern wasn't being the fastest kid on the block. It was surviving our, ahem, dry heat and living to drive another day. It's a 'conservative' build at best, but here I am 10 years and 40K miles later with the original (blue) coil, without ever having to replace a dizzy module. (OK, I swapped out dizzies mid-stream, for better mechanical bits, but not because of electronic component failure.) And 'the build' went beyond the engine itself. It included oil cooling, crankcase ventilation, fuel line placement, engine bay ventilation, and of course, complete tins. As we say here a lot, all the little bits need to be happy with each other to produce a system that works.

My point is that if you're losing electronic components, especially the same one repeatedly, take a step back and look at the bigger picture. There are many more reasons to reduce the heat in the engine compartment than just lowering CHT and oil temp. And even if your options are limited, something as simple as repositioning a coil can help a lot, too.

Last edited by Sacto Mitch

"For posterity - apparently, the coil supplied with the Magna-Spark kit is too hot for the pickup module supplied in the distributor."

Well, at least that one might be suspect, but we don't know enough to suspect all of them.  I've got two seasons on mine and it seems fine (so far!)

Something else to consider is the voltage at the + side of the coil when the engine is at, say, 3,000 rpm - Is the alternator cranking out more than 14.5 volts?  if it's more than 14.7 Volts that may be damaging the module, too.

Be a bit careful when using an old-school Ballast Resistor on an electronic ignition module.  It may not be the insurance you're seeking.

The way that they're intended to work is that they go on the +12 volt side of the coil and when they're cold they have very little resistance and provide full 12 volts to the coil.  The intent is to provide a "hot spark" when starting a cold engine to make it start easier/faster.

As the engine is running and current is flowing through the Ballast resistor, it heats up and the resistance increases to a point where a "cruising voltage" is reached (somewhere around 10 volts) and it remains at that resistance/voltage until the engine is turned off, current no longer flows and the resistor cools off.

You'll still be hitting the coil and the module with full 12 volts during startup and for a minute or more afterward.

GM used Ballast resistors for quite a few years, mostly on trucks but on some cars, too, for quicker starts.  They required a coil that worked at 10 volts and the ballast would provide that while cruising.  That also meant that you were running the coil with a heavier voltage during start-up.  Ballasts were blamed for pitting points and burning out coils from over-voltage through them, but often it was that the condenser was going bad and not bleeding off enough of the charge.  I saw quite a few condensers go bad on Chevy 350 engines by pitting the points in one direction or the other, telling you the condenser capacitance had changed from optimum.  If I bought Echlin or genuine Delco condensers they seemed to last a lot longer.  I can't remember swapping out a bad Ballast Resistor, but I might have, sometime.

If Bob's coil is on a hot shroud, I get what you're saying, @Sacto Mitch.

Is it, @Panhandle Bob? And what voltage is your coil at, engine running?

My coil sits on the trans right by the LONG trans bolt. It gets all the underhood heat, no tins in my Spyder separating hot and cold air to the engine. The hot cylinder air is ducted right under the coil by my home-made reverse sled tins.

Modern coil-on-plug setups have the coil right on top of the HOT cylinder head.

I'm not sure, but I don't think heat affects coils today like it used to back in the day.

I still am of a mind that instead of using cheap max-profit components in the points module, there would be a much lower failure rate.

Bob's problem could be as simple as a slightly intermittent connection. Not intermittent or bad enough to misfire, but electronics can be sensitive to resistance or quick open/closing current from an intermittent connection.

After two modules, I'd replace everything, because this is getting EXPENSIVE!

@DannyP posted:

If Bob's coil is on a hot shroud, I get what you're saying, @Sacto Mitch.

Is it, @Panhandle Bob? And what voltage is your coil at, engine running?



No. The coil was nowhere near the shroud. I mounted it over on the driver's side fender well.

As to the electrical connections - in a traditional induction setup, there's not a ton of wiring to be "loose", etc. You've got keyed power, a tach wire, and the wires running to the coil from the module. There's not a lot of connections to be bad.

Regarding the "as supplied" coils and MagnaSpark module failures:

I tell new guys in my trade that a point in isolation is just a point in isolation. Two points is a line. Three points is a trend.

Whereas Bob has had 3 module failures, using the entire combination "as supplied" from CBP, I'd call that enough of a trend to say that running a tame coil (or a ballast resistor, which nearly every vehicle with a Kettering ignition used to use, and which I've never had a problem running) would be the first step I'd take to help these modules live a longer life. Everybody can opine about how this ought to work, or why it might be something else - I'm not super-concerned with it. I just want Bob's (and Chappy's) setup to work, and if running a different coil fixes it, than it is what it is.

Since Chappy experienced a coil failure with the supplied MagnaSpark coil, and since the coil costs $31 from CBP, and since I've got one I haven't used yet  (because its cheesiness gave me pause), I'm going to out on a limb and say that it's at least possible we've got a trend here. If Bob runs fine on his Blue Coil, I will have seen enough.

If it walks like a duck, and quacks like a duck, it's probably not a duck-billed platypus.

Mitch has happily been running his MagnaSpark distributor for years... on a blue coil. Gordon has been running his on the supplied coil for two seasons, but I have no idea how many miles Gordon puts on his car, or if the amount of miles would be proof of concept that there is nothing wrong with the design. A 1.1 ohm coil is really, really hot to run in an induction configuration.

If I use a distributor at all (even for one more season), I'll probably just run a CDI box and use the CB module as a trigger. If I don't want to go to that much work, I'll run a coil with at least 3 ohms of resistance.

You guys do what you like. You do you. I’ll do me.

Last edited by Stan Galat

Well. Back to the drawing board. Car is backfiring and popping non stop 1st through 3rd mostly., but also at idle. Gas is good, so not running lean. Carbs are good, checked idle jets etc. Did not have this issue until the new coil has been added. Not sure what to do & am a bit discouraged at this point w a new car w only 1200 miles.

@edsnova posted:

intake leak. Maybe between cylinders?

Well. Fired it up today and now I have my blue tach light flickering. Lots of pops at idle, as well as under and over load, took it for a spin around the block and running super rough and noticeable lack of power when in 2nd & 3rd, So there are certainly some spark/ignition/alternator/dizzy issues still at play as well.  The weather is about to turn here so at least I’ll have the next 6-8 month to try and get her sorted.

@Chappy posted:

Well. Fired it up today and now I have my blue tach light flickering. Lots of pops at idle, as well as under and over load, took it for a spin around the block and running super rough and noticeable lack of power when in 2nd & 3rd, So there are certainly some spark/ignition/alternator/dizzy issues still at play as well.  The weather is about to turn here so at least I’ll have the next 6-8 month to try and get her sorted.

I think I mentioned this before but are you absolutely certain you’ve got your plug wires in the right firing order? This sounds exactly like when you’ve swapped two and you’re actually running on 3 cylinders. (2.5 actually) It’s really easy to do this, especially when your focus is on something else. DAMHIK

@Chappy posted:

On my VMC VDO gauge this light is blue on start then goes away. It is now flickering. 39CD54DA-66A8-4992-945F-FA49DA12EA0D

These are Speedhut gauges. There are three lights, blue, green, and red, left to right.

The red one is oil, the green one should be alternator, and the blue one ON THE TACH should be turn signals, as in your signal lever is either left or right.

The blue light on the speedometer should be the high beam indicator.

Cheers.

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