How long do you guys think I should let the block heater run on my JD410 if it's around 0* outside and it's been sitting for a week or two? Those cold weather starts can be mighty hard on an engine I'm told.
You are correct cold weather starts do add wear fast. It might take a bit of experimenting but i would let it run until you see temp gauge move. I have spent over twenty years as a heavy equip. mech. in colorado. We figure if you can do away with the cold start you will add close to 30% to your engine life. Also if you have a temp gun just ck block temp. Just remember all block heaters are no created equal.