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stewart and Stevenson generator


I have a Stewart and Stevenson generator that im trying to find if theres any info on it out there. I have already contacted them and they no longer have any info about it. Its powered by a 453 Detroit. Its rated at 50 kw and is a 230 volt 3 phase model. Im trying to get schematics of its wiring and controls. Any ideas where i can find anything?


I will have to take some pictures tomorrow. The model is a 4-gd-50. S&S says it stands for 4 cylinder, generator, diesel and the 50 is the kw. I do know its static excited.


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Good Luck.

I tried getting info from them about gen sets and I could get more responses from whipping on a dead horse. (at least I could get a dead horse to quiver when I kicked it)

They do have service tech's scattered around and will make service calls to people or companies with deep pockets.

They prefer to sell their eq to oil companies and they are very tight lipped about furnishing any technical info, so as they can get service contracts.

Birken Vogt

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Back when S&S was the local Detroit/Allison dealer and sold other truck products my experience was less than great also.

I asked for some product by part number. They said here it is, quoted some outrageous price. I choked a little and he backed off by like 40%. Now if you can drop the price 40% right off the bat there is some serious padding. But I don't want to do business with a company like that.


Your controls look like they are in really bad shape, and they look like first generation solid state stuff. IMHO I'd do some basic tests on the gen end (continuity and insulation), rip off all the electrics, get the engine running, and they do a fixed field flash.

Does this unit use brushes? You may need a $$pricey$$ static exciter. I'd call Power-Tronics and see how bad it might get. They likely are familiar with your static exciter and/or your generator end itself and know exactly what needs to replace it. If not, they can usually do some basic electrical measurements and know what it needs.

In the end, you don't need S&S. It's a Detroit engine with some kind of not exotic generator end.

Last, once running and genning, I'd add a control panel. Deep Sea and others makes nice control panels for not much money.


The engine runs like a champ. No issues there. Yes you are correct in everything being very dirty. I did contact powertronics. They weren't 100% sure what i need without sending a tech out. Sounds to them i need the xr8 module and static exiter add on. Also it does look to have brushes. I did find other info on the genset head. Looks like it may have a shunt generator inside yet it has static excitation.