When I got home from work Friday evening I received a phone call from my brother. His tractor wouldn't start again. So I told him I'd stop by his place Saturday morning to have a look. I thought to bring my multimeter with me. When I arrived at his place he already had the hood removed so to work on it was much easier. I first asked him to crank it over so I could hear what it sounded like. It cranked ever so slow. I put my meter across the battery terminals and it read 9 volts. It needs a charge I told him. We put it on the charger for a couple of hours and tried again. This time I put the test leads across the terminals before he even thought of cranking. When he cranked it it read 9 volts again. His battery was shot. Off to the store for a new one. We put it in, he hit the glow plugs until the dash lite went out and cranked it. It fired right up. As the engine was running I put meter probes on the battery again to see if the generator was working properly. My meter showed 14.3/14.5 volts. It's charging as it should. I received an email message from him this morning (he has the week off from work) and said the tractor started without a hitch this morning even with the wind hitting it straight on all night at 26F. Who knows if the fuel gelled or not. But at least the darned thing starts for him now. Thanks to everyone for the suggestions, encouragement, etc... It really helped a lot. Roger