you could either use the command /give 21738, or you can find it in any construction site, I found mine in black creek mill

Head all the way up the stairs to the right and onto the roof
Jump up onto the air unit and then jump over onto the construction building

This generator is broken and needs two things:
Motor Oil - 21739
Cable Reel - 21735

If you don't feel like cheating them in, I believe both can be found normally around the map.
I got my cable reel as a zombie drop in black creek mill, and my motor oil at the airport.


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Once you put the motor oil in you have a time limit, so be quick

Place the motor oil into the generator, and jump down to fix the broken cable. Head down and run all the way around to get back up the first way and put the concrete in, or just set a waypoint at the top of the building.




If you fail, you just wait for the engine to cool down and try again, you will need another cable reel and a new motor oil. Upgrading your stamina and exercise should make it easier.

thats it! you should unlock the achievement upon putting the concrete bag into the mixer