Anti-freeze in engine oil is VERY destructive to bearings. Even a small amount run for a relatively short time will pit the bearings. This material loosened from the bearings acts as an abrasive, which takes out other bearings.
My former employer was running a tub grinder with a 619 John Deere engine. It had a liner with a caviation hole, which allowed coolant into the crankcase. This at first just made more blowby but it got progressively worse. One day it was fogging so bad I could hardly see the engine. I was walking over to the engine to shut it down when it LOCKED UP. This is a 300 horsepower engine turning a 500 pound hammer mill running at 2300 rpm and it stopped dead cold. My boss came over and tried to turn it over with the starter and all the starter did was click.
They tore the engine down at John Deere and 3 main bearings spun in the block, along with 2 or three rods. An engine that could have been saved by a $7000 overhaul had to be replaced with a brand new engine costing $18,000.
If you have antifreeze in the oil, DO NOT RUN THE ENGINE.
