Ignition coil overheating - Mercruiser 140

bruceb58

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Re: Ignition coil overheating - Mercruiser 140

Is part of that suggestion keeping the points?
Same question I would have. Unless the new coil has an internal resistor, you have to keep the external resistor.
 

DJ Jaws

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Re: Ignition coil overheating - Mercruiser 140

The points are a non-issue here. Just remove the coil, the resistor, and the wire that runs between the two, and get a 12V coil. Problem solved, along with some other ones down the road. The only drawback to this is that you may have to put beefier spark plugs in it that can handle the extra power.
 

alldodge

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Re: Ignition coil overheating - Mercruiser 140

The points are a non-issue here. Just remove the coil, the resistor, and the wire that runs between the two, and get a 12V coil. Problem solved, along with some other ones down the road. The only drawback to this is that you may have to put beefier spark plugs in it that can handle the extra power.

:facepalm:
 

Bondo

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Re: Ignition coil overheating - Mercruiser 140

Originally Posted by DJ Jaws
The points are a non-issue here. Just remove the coil, the resistor, and the wire that runs between the two, and get a 12V coil. Problem solved, along with some other ones down the road. The only drawback to this is that you may have to put beefier spark plugs in it that can handle the extra power.
:facepalm:

Ayuh,.... I believe there's atleast Two posters in this thread, that have No idea how a points fired ignition works,..... ;)
 

bruceb58

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Re: Ignition coil overheating - Mercruiser 140

Ayuh,.... I believe there's atleast Two posters in this thread, that have No idea how a points fired ignition works,..... ;)
Only 2? There is a lot of wrong info in this thread.
 
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alldodge

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Re: Ignition coil overheating - Mercruiser 140

Ayuh,.... I believe there's atleast Two posters in this thread, that have No idea how a points fired ignition works,..... ;)

Please help me understand, how the increased current on the points would not were the points out faster. All points system I have ever found use a resister. Not saying they are not around but I have never seen one
 

bruceb58

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Re: Ignition coil overheating - Mercruiser 140

Please help me understand, how the increased current on the points would not were the points out faster. All points system I have ever found use a resister. Not saying they are not around but I have never seen one
You are correct. You need a resistor. Its either external or in the coil.
 

stratcat88

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Re: Ignition coil overheating - Mercruiser 140

Any other ideas about why my coil is burning up?
tach. my tach worked fine too on my first engine. we would be running for a couple of hours and start idling and the engine would start runnin rough then you would see a big spark from pos. to ground and the engine conked out.and would not restart. read some where in this forum that the tach could be the problem so start there so i did and changed all my gauges. never happened again. changed engine cause Don S said after looking at a few pictures of the engine, that i was riding on a BOMB! first salt water boat. i heeded his warning. GOD BLESS DON S.
 
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thumpar

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Re: Ignition coil overheating - Mercruiser 140

My reply was to the plugs needing replaced with a different coil.
 

bruceb58

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Re: Ignition coil overheating - Mercruiser 140

To test if your tach is an issue, just disconnect it.
 

stratcat88

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Re: Ignition coil overheating - Mercruiser 140

My reply was to the plugs needing replaced with a different coil.
thump, you are most likely right. first year with a mercruiser and dont have the experience all y'all have. when i read someones thread that sounds like something i just went through i,ll just share it.
 

boozer1966

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Re: Ignition coil overheating - Mercruiser 140

Maybe it needs a new flux capacitor.
 

splatter

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Re: Ignition coil overheating - Mercruiser 140

Did you get this issue resolved ? If so please share how . I'm having the exact same problem .I have new points,plugs, wires,rotor button , condenser , all put on at the end of last year . This trouble started when I put the boat in this year . So far I have replaced my coil , and condenser as well as checked the gap on the points and plugs.issue is still there . my thread is here
http://forums.iboats.com/mercruiser...ercruiser-missing-after-gets-warm-645870.html
 

MikDee

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Re: Ignition coil overheating - Mercruiser 140

Oops! I just posted to that link, please check it out:
 
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