I was pretty surprised when my 85 diesel Suburban started right up after sitting completely buried under a huge snowdrift since January until the middle of March,when I tried firing it up last week...
I did have to jump the glow plug relay to get them to come on,(solenoid plunger must be rusty)--and I only had one battery,but it didn't spin more than 5-6 turns before it started!...also the fuel in it is over 6 years old,and its only got about 1/8 of a tank,so I'm betting there is some water in it from condensation..usually I had to crank the piss out of that old 6.2 to get it to run,even on a warm day..it was only 50 degrees the day I started it..