I bought a used Exmark HP with the Kawasaki 23hp engine three weeks ago and the dealer serviced the engine just before he delivered it. We have only put 10 hours on the machine and Saturday just after we started mowing, the engine pulled down and stopped. We looked at the engine and noticed it was covered with oil around and below the filter. The filter was loose and all the oil had pumped out. We let it cool down for a few hours and tightened the filter, added new oil and the engine started and sounds fine. I drove it around to the shop and shut it off and it was leaking oil again. The filter was loose again. This time when I tried to tighten the filter I noticed the threads were stripped. The dealer installed the filter and I trust the mechanic. Did he get a filter with bad threads? I'm sure he;'s changed thousands of them, I don't think he would overthighten it. Does the engine have a low oil shut off? Did this damage the engine? The machine is a little over one year old and has 210 hours, it's still under warranty.