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No spark when she warms

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rocman

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"i replaced the coil ,but yhe

"i replaced the coil ,but yhe new coil has a built in resister and i'm not sure if the old did.I'm not sure if theres built in resistors in the wiring or somewhere else,my engine is aq131c,the new coil seemed to get really hot ,and the engine did the same when i put the new one on.I couldnt get any fire from my plug wires or my coil wire until she sat for awhile,any help would be great,i changed everything."
 
"Do you still have points and

"Do you still have points and condenser in the distributor, or have you already upgraded to Pertronix or Hot Spark electronic ignition?"
 
"no dindnt up grade yet,thats

"no dindnt up grade yet,thats my next project,i just don't know why i wasn't getting a spark from my coil when she quits,i changed the coil but the new one was really hot when i checked it,it has a built in resisiter and i don't know if theres anymore resisiters some where else?"
 
"For test purposes, try hotwir

"For test purposes, try hotwiring the + of the coil with a 12V wire from the battery (you will have to remove the jumper afterwards or the engine won't stop when you turn the ignition key off!!!). If the symptoms you describe don't clear, then have a look at the points and condenser in the distributor; you may find that the points are gapped incorrectly or that they are pitted."
 
"i did just that and she turne

"i did just that and she turned right over,the points are new had them installed by mechanic,but i don't know about the condenser?"
 
"i'm going to puty on the

"i'm going to puty on the pertronix,but i got to figure this out first,call it stubborn or stupid {more stupid|ha!"
 
"If your original coil did not

"If your original coil did not have an internal resistor and the new one has one, it will likely not generate a strong enough spark, as you probably have a section of resistor wire between the ignition switch and the + of the coil. How many volts do you measure at the + of the coil? If lower than 12 V, you probably have a resistor wire installed."
 
"the new one doesnt have an ex

"the new one doesnt have an external risister its built in,i put a wire to the + coil and to the + of the battery and she started right up ,should i leave the wire hooked up and let it run for awhile to see if it will still shut down on me?,i don;t have a tester ,but i;m gonna borrow one."
 
"If you are going to upgrade t

"If you are going to upgrade to Pertronix or Hot Spark, then you will need the coil you just got installed (3 ohm, internal resistor). Meanwhile, you will have to trace the wire that goes from the ignition switch to the + of the coil and either: 1) if it has a resistor on it, then remove the resistor; or 2) if it is a resistor wire, then remove the wire and run a new length of pruple wire (16 AWG) from the ignition switch to the + of the coil.

Running an external resistor together with a coil with internal resistor is not a good combination, as it will lower the voltage too much to generate a good spark."
 
"thanks alot EL , when i get h

"thanks alot EL , when i get home tonight i'll trace the wire and go from there,i'll let you know how it went ."
 
"before i traced the wire ,i s

"before i traced the wire ,i started her up ,i pulled the wire of the fourth plug and  nothing happened i the pulled the wire of the third plug and nothing happened ,i'm only getting fire from 2 cylinders,does this mean my rings are siezed or head gasket gone?"
 
"To find out if the gasket is

"To find out if the gasket is gone you will have to run a compression test.

Are you sure the wires are going to the correct spark plug? And are you sure the rotor and cap are in good condition, as well as the wires and the spark plugs (including the spark plug gap)?"
 
"i replaced the wires and spar

"i replaced the wires and spark plugs,i'm not sure about the rotor,i have a buddy thats going to do a compression test for me,also the cap is new,and by the way EL the comments on you being so readily to help people like myself with your wisdom couldn't be more correct,tks a ton,

Rocky!"
 
"I took the the boat to a mari

"I took the the boat to a marine mechanic,he's going to do a compression test for me,but i would just like to know,if i'm not getting any fire to the last three plugs,could it be still something else other than electrical,tks."
 
"El, Thanks for the informatio

"El, Thanks for the information, it is helping my problem. But....
My coil gets too hot to touch and stops sending a spark as well. The purple wire coming into the + side of the coil is just over 9 volts. Is this the correct voltage for this wire? Would it hurt the coil if I ran a wire with 12 volt to the + side of the coil?
The high enegry wire to the distributer has 2k ohms resistance and the wire states it should be 1k ohms.
The plugs, plug wires, cap, points all look good and seem to be in specs. I will recheck as soon as it stops raining.
The old coil was cracked so I replaced it with an automotive coil for testing with the same results. The new coil has a primary resistance of 1.4 ohms. I have no idea about the resistance on the old coil, again I will check when the rain subsides.
Thanks again!"
 
You may want to try with a 3 o

You may want to try with a 3 ohm coil (primary resistance) and no resistor (or resistor wire) between the ignition key and the coil.
 
"With the points open, I recei

"With the points open, I receive 12 volts on the + and - side of the coil. With points closed I receive 9 volts on + and less than one on -.
The plugs are one heat range too low, and the points were closed or so bad out of adjustment, they did not open enough to even see a difference. Points and plugs are now gapped correctly. I will add a resistor and see what happens.

thanks again."
 
"If the points never open up,

"If the points never open up, then the coil will not fire, Correct?
Could there be enough current to create a high enough charge to fire a plug?

Still searching. I will post about the resistor when I get one installed."
 
"Fixed the problem. The point

"Fixed the problem. The points were not opening enough for the coil to generate a full spark. Therefore, the coil would overheat and stop working. I did not add a resister and the boat ran for about 2 hours with out problem.

Happy Boating!!!!"
 
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