Would it be worthwhile to install a fuse into a lawnmower?
 

Last week, I tried mowing Mom's lawn with her electric mower, but when it hit the tall grass, it died, and blew the circuit. When I tried again, it just kept blowing the circuit. The bridge rectifier showed continuity, so I ordered a new one.

That was as frustrating as any of my projects. I struggled to get all of the clippings out of the screw holes, not wanting to strip the heads, but they were already stripped. I tried some different screw extractors, but the good ones tore apart the screws, so I drilled them out, and damaged the plastic housing, which was full of grass.

Somehow I do not think packing clippings around electronics is a great idea.

I checked Slickdeals to see if they had anything good for lawnmowers. They didn't, but someone commented "FYI - make sure you get the right amperage extension cord for your devices."

The neighbors said the houses up there did not have the right amperage. Do I need to plug the lawn mower into the outlet for the oven or dryer? :)

Would it be worthwhile installing a fuse into the mower so it does not blow the house circuit? Would it be better to replace her outside outlets with GFCIs?

Thanks!

You'd want some kind of mini breaker, not a fuse. You'd be replacing a lost of fuses.

GFCIs are probably a good idea if you're plugging anything in when it's wet. What else do they get used for?

What amperage is the breaker for your outlet? and is anything else on the circuit?

If your extension cord is too light of gauge, you'll get a voltage (and therefore current too) drop under load, which will mean the motor can't make the power it needs to. The longer your extension cord, the worse this will be. If you keep the load light, you don't need to worry about it. You can do that by not letting the grass grow too long, not mowing when the grass is wet, and/or by taking extra time when you do have to.

Or you can find yourself a heavier gauge extension cord. (But that doesn't mean the circuit will be able to keep up with the demand.) You've probably got a 16 gauge of at least 50 feet. A 12 gauge is what I'd want for something that could routinely pull 15+ amps. I found my 12 gauge extension cords at Costco for cheap.

You are supposed to have continuity through certain parts of the bridge rec.
The easiest way to test a bridge rectifier is close the contacts check for AC voltage going in (makes sure the switch is good) and check for DC volts on the output side. If the motor has DC potential and not turning then the brushes or motor are bad.

I use a 30 amp dedicated welder circuit and 14 gauge extension cord.
I don't use a gfi.

Oil Pan, yes, but how long? :)

When I bought my 14 gauge cord in 1999 it was 100 feet long. It's 70 or 80 now.

I replaced the bridge rectifier and mowed Mom's lawns. I tried to fix the gas one, but at least we have one working mower.

Where would I install the mini breaker?

Put it between the switch and rectifier.
I run mine on an over breakered detected welder circuit and have never killed the bridge rec.