we have a takeuchi tb175 and theres oil in the engine coolant! does anyone know what causes this???
You could have oil cooler leaking , head gasket leaking , Crack into coolant galley.have to try pressure testing radiator?
Take a coolant sample and have it tested, that will narrow your search quickly. If you run engine oil in the hydraulic system have them look for soot and other byproducts of combustion.