Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Hi, my name is***** will be assisting you.
Yes it sounds like you have two separate issues on this one.
After running for 20 minutes the engine shuts off on its own? Does this machine have an electric clutch to run the mower deck?
You can disregard the question about the clutch, I answered my own question there.
When the machine shuts off, you say that the battery is almost dead. Can you tell me what kind of voltage the battery has when the engine shuts down? I am to assume that when you start the engine the battery is fully charged?
The engine continuing to run for a short time after the ignition key is turned off is most likely a ground wire issue going from the switch to the ignition coil. The engine may have a fuel solenoid on the carburetor that shuts the fuel flow off going through the carburetor which would eventually stop the engine since it can not get fuel to it any longer.
Can you give me a voltage reading on the battery? This could be more than one possible issue you are dealing with.
If the compression release isn't working properly the engine is going to be really hard to crank over and even with a brand new battery the engine will most likely not turn or at best would be very difficult to turn over. I would be interested in knowing what the battery voltage is doing when you try to start the engine once it has stopped on you. Do you have a load tester to check the battery? If not, do you have a voltmeter that you can put on the battery and watch the voltage reading when you try to crank the engine after it has stopped.
So, there is no electric clutch therefore there is nothing else to run the battery down unless the charging system is just not working in order to recharge the battery from the initial start. I would check the charging system with the engine running, you should have at least 28VAC coming from the alternator white wire(s) and 14 - 15VDC coming from the red or black wire on the alternator. These are the wires that come from behind the starter, the engine must be running at full throttle when doing the test or check.