I went out to crank the mower which had been running all summer and sit for a week. It started just fine for about 10 seconds then died. Then it wouldn't fire at all. So I started to do the basics eliminate electrical problems then go to gas.
I tried the following to troubleshoot :
1. Removed the safety interlock and ignition switch wires from the isolated post at the throttle assembly. Did not help
2. With wires removed tested isolated post for continuity to ground. No continuity.
3. Measured 4.5K between spark plug lead and post. Cranked with spark tested attached and had a spark
4. Removed wire from lower terminal on coil and texted. No continuity to ground and 4.5K ohms to plug lead. Checked coil Gap.
5. Replaced wire from post to the coil, replaced the spark plug, reassembled, and tried to crank. Did not start.
6. Pour some gan into the carb and try again. The engine Cranked and ran for 5 seconds.
7. Tried to repeat #6 several times but engine did not fire. Retested with spark gap and did not have a spark.
Could this be a coil with an intermittent issue?
Detailed Problem description:
So the mower has a blade switch and a neutral switch with an interlock that grounds the common post on the throttle assembly. So I took the interlock and the ignition switch wire off that post to eliminate safety switches and ignition switches. Then I checked and did not have a short to ground on the post. I checked the ohms from the post to the spark plug lead and had 4.5K ohms. Took the lead wire off the bottom of the coil and found the same conunity. I tested for a spark with a spark tester and did not see a spark. Bad coil right but it didn't seem to have a short to ground and had conunity. Changed the spark plug just in case too. Put it back together and tested and it had a spark. So I poured some gas in the carb pulled it started and ran for about 5 seconds.
So thought perhaps it was the carb or plugged filter or the gas shut off. Took the gas line away from the card and the gas flow was good. But then when I repeated the fuel test could not get it to fire. So went back and checked the ohms at the post with the switch and safety disconnected and it showed dead short. Jiggled wire and the short went away. Took the lead off the coil and measured 4.5K Ohms. Tested spart no spark.
What do you think bad coil that's somehow intermittently bad? I not only eliminated the wire to the coil by removing it but also replaced it. Should I replace the coil?
I tried the following to troubleshoot :
1. Removed the safety interlock and ignition switch wires from the isolated post at the throttle assembly. Did not help
2. With wires removed tested isolated post for continuity to ground. No continuity.
3. Measured 4.5K between spark plug lead and post. Cranked with spark tested attached and had a spark
4. Removed wire from lower terminal on coil and texted. No continuity to ground and 4.5K ohms to plug lead. Checked coil Gap.
5. Replaced wire from post to the coil, replaced the spark plug, reassembled, and tried to crank. Did not start.
6. Pour some gan into the carb and try again. The engine Cranked and ran for 5 seconds.
7. Tried to repeat #6 several times but engine did not fire. Retested with spark gap and did not have a spark.
Could this be a coil with an intermittent issue?
Detailed Problem description:
So the mower has a blade switch and a neutral switch with an interlock that grounds the common post on the throttle assembly. So I took the interlock and the ignition switch wire off that post to eliminate safety switches and ignition switches. Then I checked and did not have a short to ground on the post. I checked the ohms from the post to the spark plug lead and had 4.5K ohms. Took the lead wire off the bottom of the coil and found the same conunity. I tested for a spark with a spark tester and did not see a spark. Bad coil right but it didn't seem to have a short to ground and had conunity. Changed the spark plug just in case too. Put it back together and tested and it had a spark. So I poured some gas in the carb pulled it started and ran for about 5 seconds.
So thought perhaps it was the carb or plugged filter or the gas shut off. Took the gas line away from the card and the gas flow was good. But then when I repeated the fuel test could not get it to fire. So went back and checked the ohms at the post with the switch and safety disconnected and it showed dead short. Jiggled wire and the short went away. Took the lead off the coil and measured 4.5K Ohms. Tested spart no spark.
What do you think bad coil that's somehow intermittently bad? I not only eliminated the wire to the coil by removing it but also replaced it. Should I replace the coil?
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