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Discussion Starter #1
Hello all, I am having a little problem with my 526 with 8hp Kohler. This morning I checked the plug on it since it had a miss about every 5 seconds and found the the plug had a lot of carbon on it. So I went and got a new plug and installed it and it didn't start up. Checked and found I forgot to put the plug wire back on. :fing20:

Put the wire on and it still would not start. I then took the plug out and set it on the engine and cranked it, no spark. I then put the old plug back in and nothing happens. I put the new one back on and crank but still no spark. I then noticed when ever I switch the key from ON to OFF I get a spark.

What would cause this happen so soon? It was doing fine last night mowing other than the little miss. I cleaned and set the points but that was no help. Also noticed the coil was warm to the touch. Not sure if that is normal or not. Only thing I can think of is the condenser going bad but like I said, it ran fine last night.
 

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Few things can cause that that I'm aware of. First, since you just cleaned the points, I'd check to be sure a bit of trash did not end up between them. I once found a smashed earwig in a distributor point set. Might say it had a "bug". Next, since the coil is getting warm you might check the connections hooked to it. Resistance is a funny thing and bad connections can cause a multitude of symptoms. A bad condenser probably will not cause the coil to heat but it sure would cause the loss of spark.

Since you get a spark when you turn the key there is a good chance the condenser is bad. Why this happens with a bad condenser I don't know. I've noticed a few times that you often get a spark with or without a bad condenser when the key is turned but a bad condenser will not fire the coil thru the points. Seems strange but must be because the points are on the opposite side of the coil.

The coil itself may be defective. Usually these can be bench tested by using a known good condenser and battery.

Last thing is the simplest. Since you are getting the spark with the key you may have a grounded wire that leads from the coil to to points or the points may be internally grounded. Either of these would shut down their function.

These are what I'd check for and I'm sure there are others.

Mike
 

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Discussion Starter #3
Thanks for the reply. I put my multi-meter on the condenser and saw that it would not build up resistance. So it must be leaking voltage. Hopefully I can get a new one tomorrow and see if that solves my problem.
 

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The condenser will not show resistance. If you're using an analog meter, you will see a momentary movement of the needle when connected to the condenser. You may not be able to see this with a digital meter. The easiest way to proof a battery/coil system is to simply turn the key to "on", and manually open and close the points, you should have a spark every time the points are opened. There is no need to crank the engine.
 

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One simple thing to also check is the brand of plug you're using. For whatever reason, I haven't had much luck with Champion brand spark plugs in Kohler motors. A couple of times just switching it out with an AC brand plug was all it took. But if might not be that simple in your case.....
 

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Discussion Starter #7
A new condenser solved the problem. Runs fine now. Just have to give it a work out and see if the miss is gone.

On the subject of testing a condenser with a digital multimeter. First you have to ground it by touching the wire on the base. Then with the multimeter on ohms, have one lead on the wire and other on the base. It should start at a low resistance then increase as it charges till it reaches infinite resistance or open line on you meter.
 

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One thing I love about working on Ls (maybe the only thing) is the simplicity of the electrical system.
You can hardly even call it an electrical system :) Well, ok, I suppose if it's electric start, but still...
 
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