Re: Kubota RTV 900 turns over but wont start
Lift pump is mechanical on those. No power to it, runs off of the fuel camshaft sorta like an old domestic V8.
Never bleed the system at the delivery valves. Meaning at the injector lines/pump side. It's too easy to turn the delivery valve in the pump when trying to loosen the pipe nuts...and when it does turn, it'll never run correctly until the pump's rebuilt and then re-timed. It's real easy to do it too and most times you never even know the delivery valve has turned until it does start/run and then runs like poo. Just an FYI.
There is a hex bleeder near where the rubber fuel line enters the injection pump. Bleed it there. Loosen the hex, crank engine until fuel comes out, tighten bleeder, then start the engine. It may take some cranking if it has a lot of air in it. IIRC the hex bleeder is 10mm on the old 900's.
Here's how I diagnose a no-fuel situation. Loosen hex bleeder at the injection pump, then crank engine. With the bleeder loose, it should pump some fuel out and make a mess. If it doesn't, either there is a restriction between the injection pump and fuel tank, or the lift pump (little mechanical pump) is bad....but those lift pumps aren't known to fail very often and a lot of times when they do, it fills the crankcase with fuel. Is the oil level higher than normal? IF you do get fuel there and it won't start, check your fuel shutoff solenoid. Some of them had a "large" solenoid mounted atop the injection pump area totally exposed. If you have one of those, I've seen more than one of them die...get stuck in the "off" position, and when they do, the engine will not start until a pair of fingers (yours) manually push the shutoff lever back to "run". If you have an internal solenoid...which is mounted on the back side of the engine block where the injection pump is, there's not much you can do with it...if it clicks when you turn key on, it's likely good, if not, check for power and proper ground. If no power, follow the circuit to find out why using your wiring diagram.