QuestionWe believe the issue to be one with the charging system. The tractor will start with a fresh, full charge on the battery. After running for anywhere from 15 mins to 45 mins, the tractor will stahl and wont start. The battery is drained. After putting a charge in the battery it will once again start up and run, but only for a short amount of time. After talking to several people about this, the most likely culpret seems to be the alternator not recharging the battery. Do you agreee? This is the reason we are attempting to remove the alternator and replace it if needed. Do you have any other suggestions on where to look or what to look for other than where we are going?
Thanks
-------------------------
Followup To
Question -
My mom has a 2002 MTD yard machine riding mower with a 17.5hp Briggs & Stratton Engine. Engine barely starts, and when it does, it doesn't run more than 45 minutes. (we've replaced spark plugs, battery, cleaned the air filter, replaced the fuel filter, etc., but the problem still exists.) Since the battery is not holding a charge, we are thinking alternator. I'd like to try and do this myself because of the cost and time delay (2 wks minimum) - neither of us has $200 to have the local MTD authorized service do this. We have gotten down to the crankshaft, but can't get the crankshaft bolt off - The repair ser vice tells us the alternator is accessible once you remove the crankshaft. Is there a secret to getting this off - both my husband and I have tried, and it won't budge. Once we get it off, we are hoping the alternator will be easily recognizable. Any suggestions? or are we doomed to coming up with $$$ for the repair service?
Thank you.
Answer -
The alternator has nothing to do with how the engine runs. There could be an issue with the ignition module but if you are having a separate charging issue, that is another problem altogether. The charging coils are located under the flywheel. You need to use a strap wrench to hold the flywheel to get the retaining bolt (or nut) loose. If you still can't get it loose, you would need to use an air impact to loosen the bolt. Then you would need to use a puller (harmonic balancer puller) to remove the flywheel. However, before you go tearing down, make sure you have done a full diagnosis of the charging system. You can verify the alternator is charging by putting an inductive ammeter on the battery lead or checking the charging voltage (should be greater than 13V). If it is charging, the issue could be the battery. If you have a separate running issue, you would need to troubleshoot the source of that problem separately. Please write back with what you find. Hope this helps.
AnswerThe battery and charging system do not affect how the engine runs. The ignition system is not dependent on battery / alternator voltage. That's why I suggest you have two separate issues. I am suspicious that you could have a problem related to heat with regards to the charging coils and ignition module as they are in close proximity to each other under the flywheel. I recommend that you check for spark immediately after it quits (if the ignition system is capable, it should jump a 1/8" gap). If you have no spark, I would proceed with removing the flywheel to inspect the charge coils and and ignition module. Hope this helps.
