I keep burning up my cylinder 1/4 coil Update

First I had an EMGO coil and it stopped working. So I went to the local salvage yard and picked up a used one. Worked fine for 1500 miles. Lately I noticed a strange smell. Thinking it was the seafoam I put in the tank I figured it would go away on the next tank. Well it didnt so I pulled the tank and noticed that the coil had leaked a hard plastic substance out the end. Must have gotten pretty hot. Battery level was low also. Wondering why the 1/4 coil went bad twice and not the 2/3. I am thinking regulator is bad. Any information will help. I will pick up another coil soon and check voltage. Also what year coils will work? Local shops dont carry the old stuff but maybe one of the other years are the same even if the bolt pattern is different....Russ

Here's what will blow coils:

1) Running a low resistance coil without it's external ballast resistor (if it is intended to use one).

2) System voltage running above 14V.

3) using a high voltage CD ignition with a coil not rated for the higher primary voltage that the CD will put on the coil.

Russ Jackson wrote:

the coil had leaked a hard plastic substance out the end. Must have gotten pretty hot. Battery level was low also.

Check the system battery voltage with the engine at about 3000 RPM. Sounds like it could be too high with those symptoms.

I am thinking regulator is bad.

Same voltage being applied to both coils so can't see how this would only effect (damage) the 1/4 coils.

Granted, all electronics have associated tolerances of operations but since you've already gone through a coil or two, something else has to be doing the damage...

Since the coils are burning up, I'd start looking for a short to ground on the secondary side of the coils thus excessive current draws being pulled through the coil...

Juts out of curiosity, are you running EI or points/condenser?

OMR

yeah,what omr said! :laugh:

i had a dyna ignition...and it was burning coils.....the bike came with stock coils from another model(cop bike )i replaced with cop coils theyd work for a bit then burn one...i threaded here and was told my dyna needed 3ohm coils...i bought dyna (green) 3 ohm coils and it went away.....my story......good luck russ

Ditto to all the good advice above and...

I had the same problem when I first got my KZ650.

Long-story-short... the original coil was bad and the used replacement coil was on its way to the same bad.

Solution, changed to new coils... problem solved.

Never underestimate an obvious solution.

Best of success.

And be sure when the ignition switch is turned OFF that no voltage is reaching either coil.

Good Luck!

And, And Dont let your bike sit to long with the ignition switch on.
"leaked a hard plastic substance out the end"
thats insulation, coil is or will be Kaput (shorted)

It is a points system. I never leave the ignition on. I think the low water in the battery caused it to continue charging at a higher voltage causing the coil to over heat. I ordered another coil so I can check the voltage...Russ

Russ Jackson wrote:

...EMGO coil...stopped working...used one. Worked fine for 1500 miles...strange smell...coil had leaked a hard plastic substance out the end. Must have gotten pretty hot. Battery level was low also. Wondering why the 1/4 coil went bad twice and not the 2/3. I am thinking regulator is bad....

Sometimes a coil just gets old and dies. It might pass an ohm test with flying colors, then short out a few miles down the road.

Imo, low water in the battery or a failing battery won't cause it to put out more voltage and won't cause the charging system to charge at a higher rate. And poor battery won't cause the coil to over heat. If the regulator fails and allows over 15 volts to the battery, perhaps such high voltage might get beyond the battery to the coil and thereby harm the coil -- but am uncertain of this because the battery usually serves as an electrical "shock absorber" for the system which prevents this sort of thing from happening.

Am thinking the charging system may be tested even with a battery that won't hold a charge. Fill to specs, and assure clean tight terminal connections and where negative ground attaches to engine or frame.

Then start engine and measure voltage across battery terminals. Look for 12+ volts at idle and 14+ volts at 3000rpm. With these figures, charging system is likely okay. Typically less voltage with bad rectifier and more voltage with bad regulator.

If applicable, might consider new combo rec/reg from Z1E.

Good Luck!

Russ Jackson wrote:

It is a points system. I never leave the ignition on. I think the low water in the battery caused it to continue charging at a higher voltage causing the coil to over heat.

A battery losing water is the SYMPTOM, not the cause. The regulator is overcharging it which overheats it and boils the water out and eventually kills it. In that case, the battery is collateral damage and the regulator is the problem.