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View Full Version : MSD Blaster Coil Blew Up??



Jraysray
08-10-2010, 08:28 PM
After running around for a bit (not hard) we went for an anchor and swim. About an hour later I started the boat to make sure it would start after running my radio. It took a few but it did start.

Later I tried again but no luck.

I then raised the hatch to find the TOP OF THE COIL separated from the body. It was sort of half way popped off.

What happened? Should I be worried and try to figure the cause or just replace and cross my fingers?

BTW, this happened on 8-8-10. My tow boat us expired on 7-31-10. I would like to publicly thank fellow board member for
1. Answering his phone
2. Splashing his 16 fueling it and then towing me back to the ramp. ( He was a wounded warrior from the night before )

BLAKE SULLIVAN is the man. getting towed in by one of the nicest 16's around took some of the sting out!

Conquistador_del_mar
08-10-2010, 08:35 PM
You might need to run a ballast resistor with the setup. I have never heard of one developing enough heat to blow. Bill

Carl C
08-10-2010, 08:36 PM
I've seen coils get hot and explode if the key is left on and power flowing to the coil. (on cars)

Jraysray
08-10-2010, 08:37 PM
I did but then it dropped to low. We measured it without the resistor and was around 10. Was thinking the merc harness had some type of internal resistor.

Jraysray
08-10-2010, 08:40 PM
I've seen coils get hot and explode if the key is left on and power flowing to the coil. (on cars)

Carl you might have it. I remember the jackass mech saying something about a start assist off the solenoid. I will check it.

Cuda
08-10-2010, 08:57 PM
All a coil is is a winding of wire. There is very little that could possibly go wrong with them. Some you have to mount laying down, that's to keep the wires in oil. Others don't have oil and you can mount them in any position.

Cuda
08-10-2010, 09:01 PM
I've seen coils get hot and explode if the key is left on and power flowing to the coil. (on cars)
I've seen batteries go dead from leaving the key on, but that was way back when we had points. The points would have to be in the closed position for the battery to go dead. I have never seen one blow up because the key is on. That's just too likely to happen and the car engineers should know that.

BlakeSullivan
08-10-2010, 10:12 PM
Any time it was a good reason to go out in the boat plus I was being a Huge BAby with my monster hangover .

Jraysray
08-11-2010, 12:03 AM
I've seen batteries go dead from leaving the key on, but that was way back when we had points. The points would have to be in the closed position for the battery to go dead. I have never seen one blow up because the key is on. That's just too likely to happen and the car engineers should know that.

So why would one get so hot and lift the cap? (there was oil sprayed around it) I am assuming it came from the coil.

mrfixxall
08-11-2010, 12:24 AM
if its sitting on top of the intake and that section usually gets really hot it will boil the oil in the coil..i dont like the msd coils,too many problems with them,jay do yourself a favor and get a mallory pro master coil..Its been on my x18 for over 25 years and it still kicks a$$..
here is the one im using,i have it mounted to the bell housing on the back of the engine away from the heat..http://www.malloryperformance.com/ProductDetails.aspx?modelNumber=29625&productID=2125&majID=545&minID=5455&selection=4&minselection=4

BUIZILLA
08-11-2010, 06:41 AM
either you left the key on, or the coil is wired hot all the time with the key off...

hdsadey
08-11-2010, 08:32 AM
To my knowledge all coils should have oil in them, keeps the windings from overheating and shorting out under the intense heat. If the key is left on for an extended period of time i.e. listening to the radio then the coil will get super hot and cause it to pop. The ones I've seen do that were on cars which is the same system of 12 volts going through the coil. Always seen the side of the coil blow out never seen the top blow off! A suggestion if I may? Switch your stereo to a switched circuit off 12 volts constant like nav. lights and I won't happen again, just may run your battery down!

Conquistador_del_mar
08-11-2010, 10:27 AM
It sounds like you had power going to the coil while listening to the stereo to develop enough heat to blow the coil. I had a MSD coil let go on my Eliminator once. I figured it might have been the vibration from the blower that took out the primary or secondary windings inside the coil so I bought one of these epoxy filled MSD coils for high vibration - end of problem - :yes:. Bill

http://www.jegs.com/i/MSD/121/8222/10002/-1?CT=999

Cuda
08-11-2010, 11:12 AM
It shouldn't have power running to it unless the pick up was in a closed position which is highly unlikely and to be that way more than once the chances are astronomical. It must be the coil is mounted by something hot.

Dr. David Fleming
08-12-2010, 09:57 PM
Ignition coil on internal combustion engine in really a step-up transformer. The slang term "coil" comes from the fact that it is made of two windings of copper wire around a soft iron core. the low voltage coil is energized and when it is turned off by ignition points or transistor the field collapse of the primary 12 volt winding induces a 25,000 - 30,000 volt spike in the secondary winding which leads to the spark plug.

Coils can be oil filled - older ones had PCB laden transformer oil - also they could be epoxy filled. Most had a ballast resistor which cut the current to the coil as it heated up. This reduced the likely overheating of the coil. Some coils have an internal resistor and do not need the external.

Advent of modern electronics has enabled a number of tricks to the old system which was first designed for the 1930's era Cadillac and was very state of the art at that time. Some of these tricks are feeding a higher primary voltage than 12 volts - sometimes up to 400 volts. Also multiple primary pulses fire the coil several times for each power stroke. etc.

Barry - Cuda - when I get you in my emergency room I am going to cut your gizzard out - and you won't be laughing soon!

BUIZILLA
08-13-2010, 06:33 AM
Barry - Cuda - when I get you in my emergency room I am going to cut your gizzard out - and you won't be laughing soon! if your working on gizzards, we are in the wrong emergency room... :eek:

Barry Eller
08-13-2010, 07:06 AM
if your working on gizzards, we are in the wrong emergency room... :eek:
Not if he is a Veterarian...:wink:

Cuda
08-14-2010, 11:00 AM
How did I get dragged into your argument. I've been working of stuff since you were chitting yellow and I know how a coil works withouit your dissertation of it. I have a garage full of coils, and not once did a new coil fix the problem, so put that in your gizzard and smoke it.

Start no chit with me and there will be no chit, but if you want trouble, I'll be your huckleberry. Who puts Dr on their screen name anyway jerkwad. I have three cousins who are doctors and I'm pretty sure none of them go around bragging about being doctors.

Jraysray
08-14-2010, 06:32 PM
How did I get dragged into your argument. I've been working of stuff since you were chitting yellow and I know how a coil works withouit your dissertation of it. I have a garage full of coils, and not once did a new coil fix the problem, so put that in your gizzard and smoke it.

Start no chit with me and there will be no chit, but if you want trouble, I'll be your huckleberry. Who puts Dr on their screen name anyway jerkwad. I have three cousins who are doctors and I'm pretty sure none of them go around bragging about being doctors.

Cuda,
I'm pretty sure he was kidding around.

Jraysray
08-14-2010, 06:36 PM
if its sitting on top of the intake and that section usually gets really hot it will boil the oil in the coil..i dont like the msd coils,too many problems with them,jay do yourself a favor and get a mallory pro master coil..Its been on my x18 for over 25 years and it still kicks a$$..
here is the one im using,i have it mounted to the bell housing on the back of the engine away from the heat..http://www.malloryperformance.com/ProductDetails.aspx?modelNumber=29625&productID=2125&majID=545&minID=5455&selection=4&minselection=4

That's a sick looking coil. I got another since it was an easy pick up down the street.

Donzi Vol
08-14-2010, 09:41 PM
One time, in my goofing around with wiring, I wired it in such a way that the ignition was always on...which meant that the coil was always on. That lasted for about 20 minutes until I realized what I had done and I switched it around. When I touched the coil, I screamed like a little girl because it was ridiculously hot. I would imagine that if a person were to leave it turned on for a while just sitting, a problem would arise.

So...all that to say, I would check and see if the coil was on or off the whole time that you were anchored. If it were on, probably time for some wiring alterations.

Jraysray
08-22-2010, 10:20 AM
And there you have it. I also found a wire going directly from the starter solenoid to the coil. Wonder wht it got so hot? :shocking::shocking:

Dr. David Fleming
08-23-2010, 02:18 PM
Automotive usage of ignition coil with external ballast resistor had two wires from the ignition switch - one the ON position wired primary current to the ballast resistor - this would reduce primary voltage to the coil if the resistor and coil heated up too much.

A second wire connected to START position would bypass this resistor circuit when the engine was being started - the idea was full voltage to the coil when the starter was cranking for higher intensity secondary voltage to the plugs regardless of how hot the resistor and coil were.