Of course you could go low tech and just use 2 relays a 12v fuel solenoid and a diode if the outback provides an output voltage to drive a relay on for the duration of the gen time on.
If thats the case, and your oil sender does not get up to pressure until the thing actually starts running, then the 2 relays fuel solenoid and diode works well enough.
Relay 1 is dpdt using the normally open contacts NO (normally open)
Relay 2 is dpdt but use 1 set as NO and 1 set as NC contacts (normally closed)
Use half of a dpdt (relay 1 NO contacts) driven by the outback to turn on the fuel solenoid. Also use this signal through the second relays NC contacts in series with the starter solenoid. When the outback sends the gen on signal relay 1 closes and provides b+ to the fuel solenoid direct and the starter solenoid through the NC contacts of the second relay. That gets the thing starting. (fuel on and starter turning)
Assuming your oil sender grounds out when pressure is reached, then use this to turn on relay 2. The NC contacts open and the starter stops.... now what happens when we dont start but still reach oil pressure from turning it over........
In the second half of relay 1 (driven by outback) use the NO contacts to switch B- to the second relays solenoid via a set of NO contacts in the second relay(this relays coil is wired to b+ and we switch it on via the b- from the oil sender turning on) When the sender turns on relay 2, it also will then latch itself on from the relay 1 b- NO contacts. in series with the NO contacts in relay2
So if the engine doesn't start, the oil pressure will die off, and the now latched relay 2 holds the NC contacts in series with the starter in the open position. It creates a 1 shot switch and start cannot occur until you reset the relay (momentary open switch in series with the NO contacts in relay 2 if you want this option) or the outback lets off the gen on signal.
If the engine does start, then all will be well until the outback turns off the "gen on" signal. This will reset the system until next start.
A diode in series with the relay 2 and the oil sender will isolate the sender so the B- signal on the relay 2 does not interfere with the oil low light or whatever it is hooked onto.
When the outback turns off the "gen on" signal, the fuel solenoid shuts off and the engine dies.
The Relay 1 goes open circuit and the system resets the latched relay 2 to off and the oil sender goes open, (relay 2 drops out and unlatches) .... ready for the next cycle
The latching circuit is only to stop secondary starts if the engine did not fire up.
If the oil sender turns on too early,(ie gets up to pressure before the engine starts) you can sample the ac output from the alternator to get your engine running signal to drive relay 2 instead of the oil switch, ...but we won't be able to stop the starter if it does not start..... then a timing circuit using perhaps a 555 might be in order.
And if your starting to feel bold, then you can use a third relay to turn off the fuel solenoid from the oil sender in case of low oil pressure, and use the starter signal to turn on the fuel solenoid during the start cycle (use an isolating diode from the starter relay to stop the fuel solenoid from trying to run the starter in this case)
Whew, if you follow that your better than me.. but hopefully you'll get the gist of it.
............might be low tech, but a monster to explain
.............oztules
