The Cox 09f3 Compact Tractor was manufactured from June 1983 to February 1986. Here is what they call the owner manual for it (it is combined with an illustrated parts list):
http://www.coxmowers.com.au/files/cox/pdf/09F3%2009B6%2009J6%2009M7%20OWNERS%20MANUAL.pdfThere are quite a few different models of GV400, we would need the four letter "engine code" to tell which one you have. All of them were made only in Japan. Here is the owner manual for the engine:
http://engines.honda.com/pdf/manuals/3189120.pdfNote that its oil capacity is 1.2 litres. I am surprised that it would seize up repeatedly with 0.7 litres remaining in it: there may be another problem as well as the low oil. I suggest you check for grass or other material (such as an insect nest) inside the cooling air cowl. If the air passages are clear, you may have been overloading the mower or operating on an excessive slope.
