Deutz F3L912 31 kw for Home Generator - Smokstak

Hello experts need some of your assistance !!!! I have recently aquired an older Deutz welder, a F3L912 31KW. I believe it was a miller Big Blue 400??? It didn't run due to setting up in the weather without the exhaust and intake covered. However after a little work I [removing intake & exhaust manifold, fuel lines , injectors, cleaning, new filters, fuel tank cleaned it] I now have it running. All the welding armature has been removed and left with eight 4.0 cables hanging out and provably ten #10 wires which all terminate on a block. I am trying to use it for a home generator. I was wondering how to go about getting 220/110 from it. also the shut down didnt work when pulled to stop the motor. IDK I've only ran it for a few minutes four or five times. I know AC/DC and good with diagnosing problems and working with stuff. Need a little help........ Got any close-up pictures of the generator end?

Most older welders are not much good for home backup use. Not sure what the basic setup would have been on that one though. For example Lincoln made a bunch of DC welders that could be used for running universal motors like grinders, buffers, saws etc on a limited DC 120 volt output. Works fine for pipelining and other portable welding projects, but not too useful for home backup. Another type would generate AC which would be converted to DC for welding. I have a small one like that. It has some true AC 120/240 capability, though still quite limited given the size of the set. If it's 31 Kw gen then that sounds large for a house, it may consume a lot of $$$ fuel.
Generally you don't want to have a gen with a lot higher KW rating than needed, because fuel consumption generaly scales with kw rating. And no-load fuel consumption is not a trivial cost, unless it's a diesel. Many houses here run an average load of 1-2 kw in winter. But you do need to add kw for A/C, wells, and motor starting.

If gas gen is 2X larger than what you need then after ~ 10 days of total run time the extra fuel consumption would have bought a used gen of correct size. It's mostly the baseline no-load fuel consumption that does this. Also would need larger fuel tanks.

Typical Example
7.5 kw Onan JB .6 gal/hr no-load, 1.2 full load gasoline.
15 kw Onan JC 1.0 no-load, 2.4 full load

Would estimate a 30kw gen would drink ~ 1.75-2 gal/hr no-load gasoline, and ~ 5 full load.

When I first wanted a gen I thought of mating a spare 5.0 liter car engine to a gen. That would have been a fuel cost disaster. 31kw sounds very high for a welding machine. The Big Blue 400 is a 400 amp welding machine and older machines didn't have full KVA output. I have a 500 amp Lincoln Commander that is only 12kw AC output.

Are you loozing at the data tag on the faceplate or the data tag on the engine? I am thinking the later, as 31kw engine sound about right for the output rating needed for rpm on the welding machine. Basically, the engine is twice as big as it needs to be, because it is running at half the rpm.


Can you post a picture of the welding machine faceplate where the welding controls and plugs are? Hey there..... You are exactly right..... It is off a plate on the motor. I will take a pic of it and post it. I can not locate an info plate on the gen set. as you will see all i have is a generator with cables coming out of it, which I put heat shrink on for when I ran the motor. However, they were labled. I will try to get a pic loaded today. Thank you for your time.........

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