jadonmmiller / mci-bus

The code, documentation, and other articles for our private-conversion 1992 MCI motorhome.

MCI Bus

This contains the code, documentation, and other articles we used in our private-conversion 1992 MCI motorhome.

Air Step

Our bus came with the optional air-powered entry step. It's controlled by two air cylinders; one moves it in and out, while the other locks it into place. Unfortunately, the original relay-logic controller had serious issues in its custom solenoid air-manifold. Rather than remanufacturing it, we simply replumbed the cylinders to regular industrial solenoids, then designed an Arduino Pro-Mini based controller to run it all. It was a fun project, and while the software is hugely overkill for the task at hand, the step has worked excellently for years!

Engine Swap

Needless to say, we weren't impressed with the 4.5MPG max mileage that our original Detroit 8V92 engine put out. After finding a great deal on a rebuilt Cummins M11, we pulled our old engine, fabbed a bunch of custom brackets, plumbing, etc, and proceeded to swap our engine. Our goal was to make the conversion as professional and reliable as possible. Part of that includes the schematics for the electrical. Please note the Monaco references in the schematics. Our new engine included a full motorhome engine wiring harness. We reused as much of that wiring as possible, terminating the motorhome harness into the MCI junction boxes. That's the reason for the Monaco wiring numbers.