Generac 15kw 2 wire auto start help

[Supervstech]

Not sure what you are referring to. The generator has a demand regulator inside which typically has a window of 10-12" of operating pressure for LP. Nothing else is allowed.

I think you are referring to the primary and secondary pressure regs outside of the unit. There is no "burner" inside of a generator. A demand regulator does not regulate pressure. If establishes the mixture going to the engine.

I use the term burner to refer to the consumer of the gas.
It is after all, burned...

 

[beastman]

Bummer, that's a big load for anything to handle. I get it.

Your symptom sounds exactly like valve adjustment or a weak engine like low compression. A lot of these older units don't have an hour meter so I see a lot of calls for diag. I show up and it's the same story. Hasn't been serviced in years, blah blah blah. Cranks non stop. I jam my thumb down the hole of the throttle body and it fired right up and runs like new.

I think if they fault out for whatever reason, they sit for weeks, lose prime, then can't get restarted within the 3 crank cycles.

The other issue with this unit is that the engine, electronics, and fuel system are still being made. The back end is discontinued so just be aware of that. I don't have that parts, I only stock the AVR, battery charger, and other small parts for the old square body.

Just for reference of others; I am still working on the generator. I ended up replacing the fuel regulator and the 12v coil regulator w/ plunger assembly. It starts without fluid now; but the demand regulator is still difficult to get opened up. Currently, the generator is fed directly from it's own LP tank some 15' away with a 13.5" wc regulator. I purchased another wc measurement device to see what makes it past the first stage regulator. Everything is working, initial startup is flaky. This was after doing a valve adjustment on it as well, new plugs, etc. Everything in the gas stage is brand new. If I put my hand to do additional choking after it sits for some time it will startup. Choke plate and/or some sort of prime is lost between carb area and regulator on the unit. If primed, will start manually with a 10 second crank. This is the best the generator has ran in 12 years at this point. Must be too much pressure or need another secondary regulator right before the inlet of the demand regulator. If I could modify the choke plate to cover more area I think it would startup immediately every time. This is a 2006-2007 generac 16kw model. I have a thread on ziller if anyone wants to know more.

In terms of doing a 2-wire start, I don't see why we can't solder some plugs to the rocker switch for the manual start and trigger this with the 2-wire from a solar controller to start/stop the unit instead of hacking the transfer switch.

 

[beastman]

Update on 2 wire start - I bought a solark and am planning to use the old guardian generac 16kw with the 2 wire start from the solark. Turning on the generator is actually easy. I metered out the 3 way rocker switch. The manual start simply takes 12v from the center conductor on the switch and runs it to the two contacts on the top of the switch for both auto/manual. If you are running the generator without any transfer swtich directly into the solark in manual mode this should work. I am however using a 200a generac transfer switch on the grid side of the solark which needs the transfer function (wires 194/23 12vdc). This complicates things a bit as when the power is out the 2 wire setup needs to close the contact to the automatic side of the rocker switch (the switch is a DPDT). A relay from n1/n2 sense will need to be closed from a 120vac to turn the setup to automatic when 2 wire start is called if the grid is down. If the grid is up and the 2 wire contact is called when the generator is set to auto, the generator will not start because there is voltage on n1/n2. These early model generators also have a problematic battery charger which is relatively easy to bypass, so I added some 18 gauge wires in the conduit to the generator to run a 1a battery maintainer (less than 120w) on dc from inside the transfer switch - cheap $20 noco from amazon.

 

[Bradeyboy]

It’s not that difficult. It takes a couple of relays. One relay takes the NO contact from the inverter and opens a 240 line from the inverter out. These two lines go to the Generac. On loss of 240 the generator starts running. When power is stable it provides a 12v signal back. I use that to close a contractor, that way you do not supply the inverter until you have stable power. There is another pair you will need. You need to supply the GenSet with 120v for the battery charger. With these three things you can get rid of the transfer switch. I also add a indicator when the contractors close. (I am using 2 SS relays for the contractor, one for L1 and one for L2)

Hey can you send a drawing and part identification for this? I too am looking to do this to mine.