I've replaced my 4th coil in three years ... what could be the cause of this? Or is it the Autozone coils I'm using ... ??

 

the only time i blew a coil was when the spark plug wires were bad, it takes extra power to fire, and that's enough extra to overwork the coil

to check the wires, you need an ohm meter, and they should be under 16k ohms (per meter, but they are about a meter...)

new wires are about 7k ohms.

 

coils can go bad (oil cooled). once overheated and will give an inconsistent spark.

 

More of a question than anything but when I was researching to hook up my 2nd. gen coils to a 1 st. gen dizzy it was mentioned that it is important that the condenser on the dizzy is hooked into the live at the coils and without it coil or ignitor burnout might occur .. Is that a posibility or should I throw that out the window along with the condenser ?? also if the plug wires are shorter with less resistance does that help coil life .

 

you know, that is total bullshit. tell me who said this so I can bitch slap him with my you know what ( just kidding) . I never use them condenser and I have no issues with blowing ignitor and such.

 

i don't know about the condenser, it can't hurt, but you could probably live without.

wires with lower resistance won't really help, the system is designed to work around a certain voltage/load range, and if the wires are bad, then the coil gets hot and can fail.

slightly less load isn't going to make much difference

 

I think it was one of your threads wacky I guess if I dont need it It is one less thing in the way ... So why is it there radio buzz or what ..

 

Man those 2 nd. gen coils must put out a hell of a lot of power .. I set all my stuff up on the bench when I was learning how to wire it up .. Once I had it working I put my rechargeable drill on the dizzy and spun it .. The fire at the plugs was unreal .. No goddam way I will ever grab those wires when the engine is running .. wow

 

Are your coils failing slowly or instantly when they quit? I've had one fail before because the tach wire grounded. This was on a non-rotary but same type of coil as the 1st gens.

 

I doubt it's the wires - they are (were 2 yrs ago) new Mazdatrix heavy duty wires. But i'll check the resistance - never know if there's a bad batch.

They don't fail instantly - probably every 6 or so months. This time the car started running bad a couple of weeks ago and yesterday i had the chance to do a tune-up and found the trailing coil was dead. Put a new one, set the timings, and she's purring again.

Obviously a blown trailing coil isn't much of a deal - car just doesn't run as smooth. But my concern is how soon before I blow a leading coil where i'm god knows where ...

 

I'd like to know if you need a condenser or not as well!

 

Well this is my theory not that anyone cares what I think ... A condenser has the ability to store power in a over power situation and release it in a under power situation so if you are driving along and decide to turn your lights on the condenser will very rapidly release power to make up for the momentary power drop ( Before the regulator has time to work ) Keeping the ignition system from sputtering and failing momentarily until the system is a peak power , next time maybe you turn your heater and rear defroster on the condenser does it's job to momentairly keep your ignition at a proper working voltage ,, I repeat only for a split second until the regulator has a chance to REGULATE the power supply . Now in a points and condenser system the condenser has the job of keeping the power from surging when the points are breaking ( If there was such a thing as a perfect condenser the breaker points on a car engine would never burn out they would virtually last for the lifetime of the vehicle .. This is the part I like .. However to tell if you have either a over or under active condenser if you look at the points closlely you will see that any pits in the one side of the contact will be equally matched by a raised spot on the other contact showing the direction of the power flow , If the condenser worked perfect the arc between the points would not flow either way and cause no burn on the contact surfaces .. I believe that the condensers should be left in place to do their job which is to try to keep a constant voltage where ever they are used .. just like I don't think port valves should ever be unhooked I don't think condensers should be removed they are there to preform an important job.. To keep everything in the electrical system flowing smoothly.. These 7's seem to be very fussy when it comes to the electrical systems it is possible that the removal of these components effect the operation of different parts of the vehicle .. I hope that wasn't to boreing ,,, ..

 

can i please get a summary? too much reading

 

The standard condenser used in a stock ignition system is like a half a microfarad or less. They're only there for noise reduction. They don't store jack for power; they are there to pass transients to ground, mainly to keep the ignitors from mis-triggering.

The gigantico-huge condensers used on after-market stereo systems are a completely different deal.

On the original question; You might try some stock coils. Mine are the originals that came with the car, and have never failed. It may be the quality of your replacement coils.

It would help you figure out your failure point if you could work out (using a meter) if it's the primary or secondary winding that's failing.

Also, I noticed that some of the aftermarket coils (like the Accels) specifically say not to mount them horizontally - - you need to get specific ones for that mounting position.

 

Make sure all your grounds are good and verify that the ignition system is in
good shape. Coils are usually blown by getting hot. They get hot when they are
asked to cycle to fast (not usually a problem here) or if they can't discharge fully
on every cycle.

Like Divin said, make sure they are rated to be mounted sideways. This will kill a
normal, cheapie oil filled coil. The stock coils are rated to be in this position. The
ones they sell you at the zone may be rated electrically to match the cars specs
but if they are laid on their side they may fail early.

Or better yet redo your ignition system to use better coils. See the link in my sig

 

i think those in stereo systems r called capacitors? and i don't even use those condensers.

 

"Condenser" is the old school term for "Capacitor." It's like "Rectifier" versus "Diode." Two words, same part.

 

Tim -

Your TFI setup looks good - I'll probably look deeper into that when my next set fail! Definitely keeping this thread for posterity!