Our friend, Mikey Skylar, recently bought himself a diesel car which he converted to veggie oil. He found that he wanted a better way to know when to switch his diesel tank to a the vegetable oil tank. You do this because the veggie oil must be warmed up before it can efficiently run the engine.
Being the builder he is, Mikey made a device called The Greasy Mon that tells him when his veggie oil has warmed up enough. You can either download instructions on how to build your own, or he is now selling these devices to other people who may want them for $100.
There are three thermistors which measure temperature changes based on resistance. Each of the thermistor sensors has four LEDs associated with it which the driver can see illuminate as the temperature increases. Each LED that turns on indicates that the grease has increased by 20 deg. fahrenheit in temperature. The temperature range is from 65F - 135F. Due to the sensors being placed on the outside of the fuel hoses the sensor range peaks rather low to allow for the insulation provided by the fuel hose.
Check out the video here:



Oh thank God I found this website. It’s got great energy! Thank you!
where do i donwload instructions on how to build a greasy mon and also where can i purchase one? tqhanks
Hi Ed,
You can find the schematics, source code, and gerber files that were used to create the greasy_mon here:
http://screwdecaf.cx/greasy_mon.html
If you have worked with AVR microcontrollers and surface mount parts before this project would be a good one for you to take on yourself. Otherwise you might want to purchase one. The soldering and programming skills do take a while to acquire.
There is a paypal link at the bottom of the page if you wish to purchase a greasy_mon.