1st time Poster - I was mowing for several hours today on my 1998 Craftsman GT style mower. Everything has been running fine. No problems. It has been a very hot day up near 100 degrees. I was just mowing and it suddenly died. No ability to turnover or nothing now. I checked the fuse coupling and I found a 30 amp fuse there blown. I let it sit for about 45 minutes came back with a 15 amp (what I had available without leaving the house) and nothing, but it blew immediately without a wimpier from the starter or anything. Thoughts?

 

You have a short to ground on a wire or load (starter solenoid, PTO, start switch, etc) that is supplied with battery voltage. You will need a ohmmeter. An electrical schematic makes the job easier but not required.
Disconnect the negative and positive cables from the battery. Connect one leads from the ohmmeter to the negative cable and the other lead to the 30 amp fuse holder output. (starter solenoid, PTO, main switch, etc) The meter should indicate continuity. Follow the wire attached to the 30 amp fuse holder output until you reach a termination. Disconnect the termination. If the meter indicates continuity, the circuit/load disconnected is OK and reconnect the termination and continue to the next termination. At one removed termination, the meter will indicate no continuity and the short is beyond that point. There could be parallel circuits so close inspection is required. This is where a schematic is helpful. Good luck

 

If you have a test light, I prefer using this method because you can just glance at the light to tell if it's on or not without having to read a meter. Disconnect the negative terminal from the battery and connect the test light between the battery and the cable. Put a new fuse in and it will light up the light. Disconnect the fuel shutoff solenoid on the carburetor, disconnect the hour meter if equipped, and the light should be off, but since yours has a short, it will still be on. Now you can go through and start disconnecting things and wiggling wires while you watch the light and see what makes the light go out or flicker. When you disconnect the shorted item or interrupt the short by wiggling wires, the light will go out. This gives you and idea of where the short it.

 

Cheese:
The author says the replacement fuse blew (doesn't say if immediately or after operating the ignition switch), therefore there is no battery (+) to operate the test light when the fuse blows. Therefore the test light must be self powered and placed between the battery (-) and the load side of the blowing fuse. There is no short in the wire connecting battery (+) to the fuse. The test light may stay on dimly when the short to ground is removed if there are loads normally connected to the battery (+) circuit for the state of the electrical circuit at the time of test. This is why a schematic is preferred.

 

That's why I said to put a new fuse in it after disconnecting the negative cable. Now you have power to run the light. It won't blow because the negative cable is not connected to the battery anymore, it has the resistance of the test light bulb to pass through before grounding. Once the short is removed, the light will go out. I use this method often and have found it to be much easier than using a meter or tracing wires on a schematic.

 

I didn't have a chance to get to it yesterday because of a major downpour here, but while I was running errands this morning I picked up a supply of 30 amp fuses ready to begin testing with - well I went ahead and placed a proper size fuse in AND EVERYTHING IS NOW WORKING. The only thing I had been able to do yesterday was look all over the mower for any worn wires. At this point I am unsure if my brief inspection temporarily opened the short or if there was something related to the 100 degree heat I was mowing in. Either way I appreciate everyone's help, comments and suggestions. I will be keeping those close by if this is a short term fluke and it goes down again.

 

It may be that your electric PTO clutch (if equipped) is going bad and over-amping. This is one of the things that happens sometimes when that's the case. If your PTO switch goes bad soon, you can pretty much bet on it.