Bought a komatsu PC50-uu1 about six months ago. It's been an awesome machine. I've been doing odds and ends around my house with it but nothing serious. Brought it to my buddies house the other day to start doing some more serious work and actually put some hours on the machine and get to know it's capabilities. Anyways i went to start it today and it made a CLICK and then nothing. No power. No nothing. Gauges don't work, nothing lights up, switch for lights don't work (they did work), the machine instantly lost complete power. I pulled the instrument panel apart and started checking for power going to the ignition switch. I assume there's supposed to be 12v here (i just probed around on it with the key switched on until something showed power as i don't have an actual diagram). Long story short the most i was reading was 6.xx volts. I went and jiggled the battery cables and the instrument panel came back to life. Machine cranked and started. There's an electric fuel pump on this machine (i don't know if it's factory or was added) that used to hum with the key on. it's not working now. Work lights also aren't working. I'm going to replace the ground that goes from battery negative to the frame of the machine and see if that fixes my issues. I'll report back on that. Just a few questions about this machine. 1. There's a module under the instrument panel. I thought this machine was all mechical with no electronics. Any idea what that box is? 2. The machine has plenty of digging power but it seems like it should throttle up higher. Do these machines run at low revs or should i look into maybe the throttle not fully pulling on the pump? 3. I have no dipstick for whatever gets filled to the right of the seat. Can someone measure their dipstick and the marks on it so i can fab one up (i looked around and doesn't look like i can buy one.)
Ok. Replaced ground strap. Didn't seem to help. The fuel pump died as well. I popped open the cover and the contacts all smelled burnt. I bought another generic 12v diesel pump from my local parts store. Wired that one up using the switched power from the key and nothing. Put a voltmeter on it and it was like 10.5 volts. Either the wire is corroded and can't handle a load or something else wonky is going on. I ran a temporary power from the battery to power the pump to get the machine running because i needed to use it. The lights still don't work, the glowplugs don't work now, and the fuel pump doesn't work either. (unless i leave it hooked up how i have it.) All four fuses are good. Any ideas?