Hi All - Posting this for my dad who's not great with the computer. He's been running excavators for 20 yrs, however this current machine is his first with a DEF system. New Sany machine, worked great for the first 100 hrs. Then wouldn't start one day. Checking the fuilds, we saw milky white coloration in the DEF tank, which is normally clear. Went through the whole "did you accidentally pour diesel or hydraulic in the DEF" he swears he didn't. $2,500 later, we paid the dealer to remove & clean the DEF tank. They had no clue why it happened but said the obvious "accidental fuild swap" scenario as most likely. Well, it's happening again and I personally helped him refill the DEF last time, so I know it wasn't an accidental fluid swap since it was cleaned. Any ideas? I know the urea turns white when it crystalizes, but I've never seen it turn white in solution like this. Thanks,
Usually means air or water was introduced to the system. Check DEF cap and or any vents.
Most DEF tanks have a heating tube inside them with coolant in it. I wonder if there could be coolant getting into the tank.
Thanks for the quick replies guys. I'll check the cap and vents. I'll run the coolant tube idea by the dealer (we're not dismantling much yet since it's still under warranty)