I have a yanmar longhorn 6 seater which I believe is having fuel delivery issues. It will run off of starter fluid and will sometimes run on gas but will not idle. Fuel pump is new and verified to put out 56 psi. Injector is new, I'm reading 10.5 volts at the injector, gas is new. The unit will run when the engine symbol is not present at the gauges. Diagnostic port doesn't appear to be present, can't find it where yanmar says it should be. Oil is full but old. Any ideas what's going on here? Is there a maintenance function that will shut this machine down if it has old oil?
