Small Engines (Lawn Mowers, etc.): Mower blows fuses immediately

Question
QUESTION: I have a 1987 Toro riding mower model 57360.  It worked fine until one day the mower deck suddenly disengaged but the engine continued to run.  I turned off the key to see what was wrong and since then I have been unable to start it.  It doesn't even click when I turn the key.  The fuse right behind the key switch is blown, and now blows immediately when I replace it even with the key off.  I even tried taking the connector off of the key switch to see if the switch was bad but the fuse still blows even though the wiring harness is unplugged from the key switch.  I tried replacing the worn battery cables but no other exposed wires are obviously worn.  What's wrong? It never had a problem before.

ANSWER: Dis-connect the clutch and charging system connector to isolate them from the wire harness.

You have a direct short to ground causing the fuse to blow.

Have you had the battery tested?  I would start with a know, good battery as I have had them fail in the past.

Do you have a mutltimeter to test/check for shorts to ground?

Eric

---------- FOLLOW-UP ----------

QUESTION: I have a multi meter.  I am not really sure how to go about spotting the exact location of the short though.  I am sure the battery is good as it is new.

Answer
These are usually the batteries I have trouble with...new batteries.   Many years ago, there was a bad batch of batteries that had reverse polarity issues.

Buy a bunch of fuses...probable 10 or so.

Next, download the parts manual (schematic is in the parts manual)

http://www.toro.com/en-us/parts/Pages/PartsDetails.aspx?mybeid=4146&serialNumber


Go here: Toro Product Center Typing in this model number in the "Enter Model Number" block will do it: 41-20OE01. After clicking on the red "Search" button, click on the red "Manuals" tab and it should give you a list. You should see the Demystification manual listed. Be prepared, even on a high speed connection, it takes a while to download those 500 plus pages.

Try this URL:

http://www.toro.com/en-us/parts/Pages/PartsDetails.aspx?mybeid=3218&serialNumber


You are looking for the demystification manual(523 pages)...it is a good Toro manual for you mower that tells you how to check the electric clutch and all the other switches.

I would start trouble shooting by disconnecting the the clutch and the charging system (the connector coming out of the engine.  See if the fuse still blows.  If so, disconnect the clutch switch, check to see if the fuse blows.  If it blows, disconnect the key switch.

If it still blows then there is a wire shorted to ground.  Most likely the wire will be behind something, it  got pinched and rubbed through the insulation.  Also, pay very close attention to all areas where the wire runs through holes or next to any metal part.

It can be difficult to find a bad wire or you may get lucky and find the clutch is the issue.

Eric