[77newell]

Hey Phil; it's possible you don't have one. Assuming you have an 8V92 the high idle operates differently than on the electronic engines. On the electronic engines all you need is a switched input to the ECU and the electronics take care of the rest. On our mechanical engines the governor needs to be mechanically bumped up to make the idle go high. There are a variety of ways of doing it. According to my Detroit Diesel manual if you have a built-in high idle you will find a small air cylinder on the top and a small one on the side of the governor. An electric switch up front would then operate an air valve controlling the pressure to these cylinders. If you have the Jake Brake on your coach I don't see how it is possible to have a high idle setup since the Jake buffer switch at the governor uses the place where one of the cylinders goes. On my 77 coach I have Jakes and use the cruise control to obtain high idle.

Take a look at your governor, if you have the two small cylinders you will have a high idle switch somewhere. Without the cylinders you don't have high idle unless you have a non-standard arrangement. A non-standard arrangement would entail at a minimum something to tweak the throttle input at the governor.

everything I know just ain't so