defective coil

[smosher]

I have a oil flamethrower coil with the EI and .85 ohm ballast resistor.

Last week in bring the boat in for winter storage the engine shutdown.
My Son turned the motor over and guess what no spark. Now thinking of all
of the threads on the coil and ballast resistor I was thinking can't be the coil, maybe the resistor or my wiring is bad. Couldn't find my meter so went home and ordered a coil from Moyer as I didn't have a spare. Found my meter and went back to the boat with coil and meter in hand today. Popped in the coil and started right up. I ohmed out the coil and it was open.

We did run the motor hard in going up river to make a couple of bridges. Ran like a top until it stopped like the switch was turned off.

Steve

[hanleyclifford]

Most likely you had too much voltage at coil+ in spite of your resistor. The hard run upriver would have brought your batteries to top charge and left your alternator free to "drill" that coil. Test your new set up at coil+; it only takes about 10 volts to run an A4 (and keep a cool coil).

[ndutton]

There's a statistical failure rate with any manufactured product so it's possible your installation had nothing to do with it. Scrutinize the balance of voltage, resistance and amperage with the new coil to be sure. Likely the resistance will be significantly different with the replacement.

edit:
About that 10 volt comment to run the engine, if you set up your supplemental resistance to meet that goal at cruising speed (alternator contributing), the voltage will be considerably lower during starting (starter load and no alternator output), maybe low enough that you'll be forced to add the wiring complexity of the solenoid 'R' terminal resistor bypass just to get her started.

Please think it through.

[sailbristol]

I use a mallory variable ballast resistor .75 cold at starting and warms up to 1.25 while engine is running

[smosher]

Hmmm, I did use my standby battery and it was fully charged, I didn't check my volt meter but on the amp meter was a tad above + 0, wasn't charging the battery, so the voltage must of been max 14.2. My notes says the flame thrower coil had a resistance of 3.3 ohms and with the .85 the circuit should of been drawing 3.5 amps. The new coil from Moyer has a resistance of 3.8 and with the .85 ballast draw should be a little over 3 amps. No Issues with starting with the new coil and the .85.

The boat is on the hard and winterized so I'll look this over again next spring. My winter project is to redo all of the standing rigging and I have northeast rigging unstepping the mast this week. The boat is a 74 pearson p30 and as far as I know the mast hasn't been down. I plan on redoing the rigging myself anyone have any tips ?

Thanks

Steve

[hanleyclifford]

We love projects

Why not post a few pictures of your rigging, especially terminals - maybe start a new project thread?

[smosher]

Ok Hanley I will, the mast wasn't down yesterday and I'll check next saturday and post some pics on a new thread.

Thanks

Steve

[dvd]

I fried a flamethrower coil after I installed electronic ignition. I just went back to the plain old coil I got with the boat and its now lasted several years. I do have a new Moyer bought coil still in the box in case anything happens. So much for the cool looking flame thrower coil. It was toast.

dvd

[ndutton]

dvd,

Your experience is an inverse testament to Pertronix's claim that their Flamethrower™ coil the "perfect match" to their Ignitor™ Electronic Ignition product. We covered it extensively in the marathon Coil Input thread.

[dvd]

Neil,

Yes, we did cover the coil issue quite extensively.

dvd

[sastanley]

smosher. I've wired up the "R" terminal and it was easy...not disagreeing with Neil that additional complexity is involved, and some of my issues this summer were definitely related to the level of complexity I created, but I have had less trouble with my coil the lower the voltage is. The addition of the "R" terminal helped with instant start up. (I am running over 2 Ω of resistance.)

Hanley, that thought about how the alternator's charge can get redirected to the coil after that batteries are up is an interesting concept. I never thought about that, but it seems plausible to me. I may try to monitor this possible condition with one of joe_db's favorite digi meters from fleabay.

[ndutton]

Shawn referenced it so I had another read:

Most likely you had too much voltage at coil+ in spite of your resistor. The hard run upriver would have brought your batteries to top charge and left your alternator free to "drill" that coil.

I'd like to hear more about this. How exactly does it happen? Any measurable evidence?

I had a 9 hour continuous motoring run for the arrival of the U.S.S. Iowa, batteries were certainly topped early on, a 0.885Ω resistor installed on the exact same coil as Steve. Why would his coil get "drilled" and not mine?

If this were even possible wouldn't we expect repeatable results? Right now I'm having huge problems with the premise, the reason I'm seeking support for it.

[hanleyclifford]

Shawn referenced it so I had another read:I'd like to hear more about this. How exactly does it happen? Any measurable evidence?

I had a 9 hour continuous motoring run for the arrival of the U.S.S. Iowa, batteries were certainly topped early on, a 0.885Ω resistor installed on the exact same coil as Steve. Why would his coil get "drilled" and not mine?

If this were even possible wouldn't we expect repeatable results? Right now I'm having huge problems with the premise, the reason I'm seeking support for it.

Don't make it more complicated than it is, Neil. Quite simply most users run an A4 for a few minutes to get in and out of the marina and in many cases I suspect never get their batteries up to full charge where the alternator can "drill" the system at full voltage allowed by the regulator for any appreciable time. So for many the issue never arises. Those of us who make long runs under power with big alternators and many batteries need to be especially concerned about this. BTW, Shawn; this is still looking for a site - http://www.defender.com/product.jsp?...0009&id=341907

[ndutton]

Sorry Hanley but that doesn't answer the questions:

1. If true, why Steve's and not mine? We have virtually identical setups and virtually identical usage, his failed (assumed "drilling") and mine hasn't. If this were a real issue, wouldn't I have experienced the same?
2. You said I suspect never get their batteries up to full charge where the alternator can "drill" the system at full voltage allowed by the regulator for any appreciable time. This assumes a variable voltage output from the alt/reg when in fact it's the amperage that varies. The voltage strives to remain constant. Man, I can't even believe this discussion has come up again.
3. Are you suggesting ANYONE running their engine with fully charged batteries risks coil damage from the alternator? Or that we don't see the damage because nobody runs their engine very long with fully charged batteries?
4. How much run time with fully charged batteries does it take to damage the coil? Steve didn't mention a time span but I did, 9 hours continuous with a 100 amp alternator capable of putting out 50 amps @ 2000 RPM at ~14.1 volts constant.
5. What about a cross country auto trip? Their batteries will be fully charged early on, their charging system is the same as ours and they'll be running for hours upon hours, day after day. Do their coils get "drilled"? My folks' 1960 Mercury station wagon didn't have coil problems in 1964 on such a trip. Six weeks of daily extended operation.

Don't make it more complicated than it is, Neil.

This isn't complicated. You suggest running for an as yet unspecified time with fully charged batteries can "drill" a coil to failure and I'm not buying it without some solid support.

My only reason for challenging the premise is to maintain solid information on the forum. If this is true it should be supported. In fact I'll open it up: Does anybody have experience or a reference in support of the premise? If it's true it's new territory to me and I'd like to learn more.

[JOHN COOKSON]

Ok Hanley I will, the mast wasn't down yesterday and I'll check next saturday and post some pics on a new thread.
Thanks
Steve

Steve
This is really a good idea.
I got more than an eye full ane a ear full of information from the professional rigger I hired to advise me when I rerigged the standing and running rigging myself.
Here's some free advice already: Go 1 or two sizes larger than you have now on the standing and running rigging.
Now back to coils.

TRUE GRIT