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wendelator

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"I just replaced my points,cap

"I just replaced my points,cap, rotor, coil ,plugs, and wires.Now i have no spark or current to my coil. WShen i hooked it to a meter ihave 12 from the + coil to a ground but when i turn it over no spark?

Thanks"
 
"Put the old coil wire back on

"Put the old coil wire back on and see if it runs. I have seen a lot of them bad out of the box. Next, check your points gap and dwell.

If you didn't run it before you changed these parts, it's going to be a lot harder to determine where the problem lies. You probably have the stator around the crank, right? The voltage regulator is notorious for going bad at the drop of a hat and doesn't tolerate bad grounds at all. The often freeze, too, because of incomplete draining during winterization. If the regulator is bad, find the replacement kit that uses a regulator alternator instead of the old system- you'll spend a lot less money and be a lot happier."
 
"It ran last year, unfortunatl

"It ran last year, unfortunatly i tossed the old coil....There is no stator that was changed to an alternator before i purchased it... If the points gap and dwell are off would that cause it not to start. It will turn over.. is there a trick for setting the points or gap?

Thanks for your help..."
 
"If there's a plastic cove

"If there's a plastic cover on the flame arrestor or a sticker on one of the valve covers (more likely that this is the case), it should indicate the gap and dwell. If not, call a Mercruiser dealer and ask what they should be set to.

If you look at the disrtibutor rotor shaft when you remove the cap and rotor, you'll notice that there's an area where the points are that has four lobes, or points that are rounded over. The fiber or plastic wedge on the points rides on this and when the point lines up with the wedge, the points are supposed to open. That little red or black plastic 'pill' is grease for the wedge, so the friction doesn't wear it away.

The theory behind the ignition system is this:

when current flows in a conductor, a magnetic field is created. If a set of windings has voltage applied to it, the magnetic field can be very strong and when you have another set of windings around or near the one with the voltage, the second set can be "saturated" by the magnetic field. How much saturation occurs is dependent on how long the voltage is applied to the first (primary) winding. The time interval is determined by the "dwell angle", and is caused by the points being kept open for a period of time that allows the coil to saturate. When the points close, the magnetic field collapses in the primary and the secondary and a strong voltage change occurs, causing the spark to jump at the plug tip but only if the voltage is sufficient. If the coil is shorted, the points never open or close for the needed time or if the condenser is faulty, the voltage will never be enough to cause the spark to jump, or it won't be intense enough. This is called a "collapsing field" system, since the voltage increases drastically when the points close.

The points are set with a feeler gauge and the distance should be listed on the previously mentioned cover or sticker. There will be a range, in the area of .016"- .024" and a dwell angle of about 26º- 34º. These numbers aren't necessarily what yours needs, so don't just set it to them. Get the correct specs from the dealer.

You can get a dwell meter at Sears for about $35 and there are digital ones available, too.


the coil is a transformer, since it has a primary winding and a secondary winding"
 
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