Airco 250 Amp DC Hornet D-E

[QTRHOSS]

Newbie here and I need some expert help.
I have an Airco 250 Amp DC Hornet D-E that has a Kubota D850 3 cyl diesel engine - engine runs strong but that is it. No excited electrons from the generator - zero... Weld or AC.
I am having a tough time finding any real information on this machine. I know Miller and Generac made machines for Airco but nothing I have found really matches up to this one. I would like to find a diagram and generator test procedure. The engine is worth $ but I would really like to make it work since it is in really great shape rather than scrap the unit for the engine.
Any assistance would be greatly appreciated.
I have photos of the placards, machine, the engine and all, but am not yet fully aware of how to add them to this post. As I lurk around the site I am sure I will figure it out.

[J. D.]

I had one of those that I ended up junking around 2007 I never had much in the way of manuals and such, but I was able to chase down the manufacture of the voltage control unit to Generac in Wisconsin. The electronic voltage control was what was originally wrong with mine. After paying $453.00 for one and having only last a few hours, I decided to try and repair the one I had and while the schematic for that is proprietary information, a tech there was able to read me the resistor values for my unit. I used that machine for around 10 years and had no problems until the day all the majic smoke came out. I guess you should try contacting Generac welder service and see if they can help you. Good luck.

[QTRHOSS]

Thanks J.D.
That is what I am concerned with. This thing really "looks" good. The windings and all are really clean with tons of brush material remaining. I bought it as-is and I don't know if the go-smoke is still in it or if it was released back to nature. I can tell you it would be a shame to scrap it - but the engine alone is worth more than the welder together and complete since it is apparently the same engine used in some small garden tractors, mini-excavators and bobcats.



And I have no idea why it wants my pic's sideways...

[J. D.]

If you can find a good generator/welder repair man, he might be able to go through the back of your control panel and locate your problem for you. If I remember right, that machine uses a bias voltage from the 12 volt charging system to energize the generator fields. So if your battery and charging system are not up to par it might not engage the relay that charges the generator field wiring. Also you could just have a bad relay. I believe that the D-850 Kubota is rated at about 18 hp and is just a little light at the max amp settings. But the nice thing about that welder is that it generates 220 vac at the idle/low speed setting and gets around 8hrs of ac power for around 5 gals of diesel.

[QTRHOSS]

Thanks again J.D.

I noticed that the alternator does not charge the battery - but I figured that system was completely separate. Now I have renewed faith that this old girl could live again, so that will be the focus to start.

As far as the engine, once again, you are on the money at 18 hp net. The economical sipping of fuel is quite attractive, and I only rarely go above 185 amps for the games I play so it sounds like it would be worth while to invest a little in it before I cut my losses.

I have other welders so I am not in dire straights, but it is awful hard to scrap something that has potential.

Once again, thanks!