jonw440 196 #1 Posted July 11, 2021 The K181S has spec of 30803 k181s spec 4152243. Its in a 198? C85. The model and serial number is long gone. We have no spark. Gaped new plug at .025 and cleaned coil wires. How can I test the coil and condenser? Could the magneto be dirty or bad? Share this post Link to post Share on other sites
pfrederi 18,664 #2 Posted July 11, 2021 If you have a coil and condenser you do not have a magneto but you do have points. First see if you have 12 volts at the + terminal on the coil (switch on run) if you do hook a test light on the - terminal of the coil and crank the engine ..light should flash on and off. If it doesn't clean the points. 1 Share this post Link to post Share on other sites
jonw440 196 #3 Posted July 11, 2021 I checked to voltage and it shows 12.7v at coil from both sides of the coil with the key in run position. I gaped the points to .020 and cleaned the contacts but still no spark. Bad coil or bad condenser? Can I test them with digital multi meter? Share this post Link to post Share on other sites
pfrederi 18,664 #4 Posted July 11, 2021 Primary (small + to small -) should show 3-5 ohms Secondary test center terminal to small - should show 6k -10k ohms If you have a spark plug tester you can try the the pictured test (I just had a coil issue it had resistance readings close to above but wouldn't generate a spark on the machine or in the pictured test.... There is no practical test for condensers except to disconnect it and see of spark returns... Share this post Link to post Share on other sites
squonk 43,794 #5 Posted July 11, 2021 2 hours ago, jonw440 said: I checked to voltage and it shows 12.7v at coil from both sides of the coil with the key in run position. I gaped the points to .020 and cleaned the contacts but still no spark. Bad coil or bad condenser? Can I test them with digital multi meter? You need to check the voltage of the negative side of the coil while cranking. Share this post Link to post Share on other sites
jonw440 196 #6 Posted July 11, 2021 Thank you for the tips! BUT I found out what the problem was........... BAD SPARK PLUG! I took a good one out of my 314-8 and checked for spark and wouldn't you know that's all it was, I saw a great spark. Put the plug back in the motor and a shot of juice and she light right off. Now I am dealing with a bad fuel pump. That will be another thread. Thanks again for the help! Share this post Link to post Share on other sites
pfrederi 18,664 #7 Posted July 11, 2021 7 minutes ago, jonw440 said: Thank you for the tips! BUT I found out what the problem was........... BAD SPARK PLUG! I took a good one out of my 314-8 and checked for spark and wouldn't you know that's all it was, I saw a great spark. Put the plug back in the motor and a shot of juice and she light right off. Now I am dealing with a bad fuel pump. That will be another thread. Thanks again for the help! It was a new plug and it was bad...let me guess it is a Champion.... Share this post Link to post Share on other sites
Handy Don 14,061 #8 Posted July 11, 2021 1 hour ago, pfrederi said: Just adding that the spark should happen as the yellow wire is removed from the negative coil terminal, not when it is touching! 1 Share this post Link to post Share on other sites
jonw440 196 #9 Posted July 11, 2021 1 hour ago, pfrederi said: It was a new plug and it was bad...let me guess it is a Champion.... The bad plug was not new. It was in the tractor the last time it ran about 12-14 years ago....... Share this post Link to post Share on other sites