Bad condenser will spoil your fun.

[RED-Z06 2,221]

Cranked up the K181 to get it good and hot to change the oil and let the new paint cure.  The coil, points, condenser, wiring, etc only has about an hour on it.

 

10 minutes at about 3000 rpms it sputtered, gas looked okay but i put about a quart more in, touched on the tune a bit and i could turn it lean until it shot flames out the stack...then rich until it puffed black, but there was never a point where it ran right.  Tried a new plug..no change, dropped the bowl...clean.  i pulled the points cover and the points had a bit of wear, more than expected.  I filed them and regapped at 0.018", and cranked on it, started and ran but the points looked like they had more spark than the plug.  I swapped the old condenser back on and the sparking stopped and it immediately ran correctly.  Aftermarket condenser...go figure

 

[953 nut 55,212]

The Kohler 230722 Condenser fits all battery ignition single cylinder and twin cylinder from the K-90 to the K-582.  The 235786 condensers are for the magneto equipped Kohler engines only K-161 to K-301

The unit of measure for a condenser is the Farad. Many electronic components like radios and TVs use capacitors that are in the microfarad range (ten to the minus six power Farads) and our small engines use a condenser that is in the nanofarad range (ten to the minus ninth power Farads) which is based on the voltage range they work in. A magneto ignition system uses a 100 to 250 nF condenser and a battery ignition system uses a 200 to 500 nF condenser. A good multi-meter will have a capacitor testing function.

Armed with this information you can walk into your auto parts store and get a very confused look on the face of the person on the other side of the counter. The capacitance is not listed on the package and probably not in any of the on-line data they have for the condensers they stock. You just have to go by the application chart and be sure that the condenser you are buying is for the type ignition system your engine has, not just the horsepower or engine size.

If an engine idles well, but runs erratically when revved up, like it hits and misses, pops and backfires, then chances are, it needs a new condenser/capacitor. And always install a condenser/capacitor with the wire facing downward so rain water and/or when washing off engine, water will not enter inside condenser/capacitor, ruining it. With water inside the condenser, this will also allow it to idle well, but cause it to run erratically when revved up.

What is a farad (F)? A farad (F) is the standard unit of capacitance (C) in the International System of Units (SI). It indicates the ability of a substance to hold an electric charge. The value of most electrical capacitors is expressed in farads, microfarads (µF) or nanofarads (nF)

[Achto 27,570]

I chased what I though was a carb issue long enough to frustrate the crap out of me. In the end a new condenser solved the issue. Was amazed at the way a bad condenser made the engine run.

[WHX?? 48,815]

[RED-Z06 2,221]

17 minutes ago, Achto said:

I chased what I though was a carb issue long enough to frustrate the crap out of me. In the end a new condenser solved the issue. Was amazed at the way a bad condenser made the engine run.

Its bizarre right?  Idles like a rolls royce, coughs and pops off idle

[953 nut 55,212]

The quick and easy down and dirty way to see if you have a bad condenser on a battery powered ignition system is to disconnect the condenser wire from the coil. If the condenser was bad the engine will run better. Don't just leave it disconnected or your ignition points will burn up.  When the points are closed and the current if flowing through the primary winding of the ignition points the condenser is just sitting there doing nothing. When the points open the magnetic field collapses and a momentary high voltage is induced into the secondary of the coil. At that moment a strong electrical arc would form across the points without a condenser of the proper size in the system to quench the arc. 

[c-series don 8,696]

I have a C-175 with the factory Series 1 17hp Kohler. For the life of me I couldn’t get that damn thing to run properly. In fact I got so frustrated with it that I gave up and pushed it outside and now it’s under a tarp. By the way I hate leaving stuff outside. I’m by no means the best small engine mechanic, but I’m certainly not the worst. My high school shop teacher taught me basically everything I know about this stuff. He was/is a wealth of knowledge. I was even thinking about loading up the tractor and bringing it to him and saying here, you figure it out!! I’m happy to say that we are still friends after I graduated 36 years ago. Anyway, one thing that I didn’t do was change the condenser! Since this is the feature tractor for this year’s big show, and this thing needs a full restoration I’m thinking about trying to get it done in time. I will however not do anything to it until it runs perfectly. I have a few other irons in the fire right now but then I think I’ll start by changing the condenser!! 

[RED-Z06 2,221]

52 minutes ago, c-series don said:

I have a C-175 with the factory Series 1 17hp Kohler. For the life of me I couldn’t get that damn thing to run properly. In fact I got so frustrated with it that I gave up and pushed it outside and now it’s under a tarp. By the way I hate leaving stuff outside. I’m by no means the best small engine mechanic, but I’m certainly not the worst. My high school shop teacher taught me basically everything I know about this stuff. He was/is a wealth of knowledge. I was even thinking about loading up the tractor and bringing it to him and saying here, you figure it out!! I’m happy to say that we are still friends after I graduated 36 years ago. Anyway, one thing that I didn’t do was change the condenser! Since this is the feature tractor for this year’s big show, and this thing needs a full restoration I’m thinking about trying to get it done in time. I will however not do anything to it until it runs perfectly. I have a few other irons in the fire right now but then I think I’ll start by changing the condenser!! 

Certain cant hurt to swap one off another engine real quick to test.

[kpinnc 12,017]

Got a buddy with a C-81. That thing ran like crap, as if under a load. Ran hot too. Made no sense at all. Everything seemed to be correct. 

 

Changed the condenser and it purrs like a kitten. I'd have never thunk it was true, but it was.