I have a Craftsman push mower with a 6.25hp, 185cc motor. I believe it is a Techumseh Motor. It started right off the first couple times I used it this year. However, the last time I went to start it a couple days ago, it would not start. Not even an indication it wanted to.
In the past, it would only do this after it had been running a while and was hot. If I stopped it while hot, it would refuse to start until it cooled down. But now it won’t start when cold whereas before it would almost always start first pull when cold.
So, I pulled the plug and there is gas in the cylinder and on the plug. I took some household electrical wire and grounded the plug to the block with the plug wire on the plug and I see no spark at all with the plug. I removed the kill switch wire from the magneto thinking it might be shorted as well and it still would not start. I installed a new spark plug and it still wont start and I still see no spark. I also removed the magneto, filed the mounting holes on the magneto and block to ensure a good connection and still nothing. So, I am thinking the Magneto is shot. I read somewhere that a motor that is hard to start or won’t start when hot is a sign of a magneto going out as well.
Before I spring for a new magneto, is there anything else it could be? Is there any definitive way to test the magneto? Any suggestions on where to go from here?
And just to be sure everyone is on the same page, here is what I am calling the Magneto. It seems there are two or three common names (Coil for example) for this part and I didn’t want any confusion.
<img src="http://www.doityourself.com/forum/attachments/outdoor-gasoline-electric-powered-equipment-small-engines/66511d1464231188-no-start-issue-seems-like-no-spark-magneto.jpg" border="0" alt="Name: Magneto.jpg
Size: 48.5 KB” />
I pulled the flywheel tonight hoping to find some jacked up points but seems my mower doesn’t have points so I am at a loss as to where to go from here. My thoughts are an issue with spark. I cannot see a spark when I turn it over and I even tried using myself as a spark meter. hahaha. It was hard to turn it over while holding the spark plug wire and touching the block at the same time but I did get a small jolt. Nothing like I expected however. Since there are no points, I am thinking it has to be a bad coil (magneto). But, I don’t want to spring for a new one unless I know that is the problem. Does anyone have any further suggestions?
Here is a photo after I pulled the flywheel off expecting to find the points and condenser. So does this have electronic ignition? Or is that just a dumb question?
<img src="http://www.doityourself.com/forum/attachments/outdoor-gasoline-electric-powered-equipment-small-engines/66512d1464231282-no-start-issue-seems-like-no-spark-techumseh-motor-1-.jpg" border="0" alt="Name: Techumseh Motor (1).jpg
Size: 50.0 KB” />