Does this contraption have anything to do with Jake Brakes?

[Bryan]

hey guys, does this contraption have anything to do with Jake Breaks?

The reason I'm asking... I'm trying to find a spare wire that has already been run from the driver panel to the engine compartment. I found a group of 5 wires at drive panel, and only 3 of them were being used, and they are being run to the jake switch, I also found a group of 5 wires running to this picture, and of course 2 of them were not being used and they are the same colors. I tried putting some voltage to one of the spare wires at the driver panel, and use a test light at the engine to see if power was running thru it, and it didn't seem to have any power on it. Any other suggestions on finding a spare wire? And again, what is the contraption in the picture? Thanks!

[OneLapper]

RPM sending unit, I would say.

[luvrbus]

Like Mark said a tach drive pulse generator the white wire goes to the tach I don't where the 3 wire grey goes to but certainly not the tach or Jakes, it only take 1 wire from switch to the buffer for a single stage Jake take 4 for the 2 stage Jakes The generator wires should be easy that will be be a pair of twisted wires     

[Bryan]

Like Mark said a tach drive pulse generator the white wire goes to the tach I don't where the 3 wire grey goes to but certainly not the tach or Jakes, it only take 1 wire from switch to the buffer for a single stage Jake take 4 for the 2 stage Jakes The generator wires should be easy that will be be a pair of twisted wires     

he grey wire you are seeing is coming down from the group of 5 wires I had mentioned earlier. At the bottom of the picture the 3 grey wires are connected to the white wire which also has 3 wires in it, and runs to the device that you guys are saying is an rpm controller. Am I thinking of this correctly?

My jakes have 2 levels of braking. So you are saying that uses 4 wires correct? where would I find these wires at the engine?

[luvrbus]

At the buffer on the governor going to each head at the front of the engine ? do you have a off/on toggle and a hi/lo toggle there are so many ways to wire the Jakes one never knows without tracing in the end all will connect to the buffer switch if you have one then to the heads     

[Lin]

As mentioned in another thread, a tone generator makes tracing wires relatively easy.

[RJ]

Bryan -

That device is NOT an rpm controller, it's the pulse generator that sends the tachometer it's signal.

Just to help muddy the waters some more.   

FWIW & HTH. . .

[Bryan]

Bryan -

That device is NOT an rpm controller, it's the pulse generator that sends the tachometer it's signal.

Just to help muddy the waters some more.   

FWIW & HTH. . .

Ever since the automatic transmission has been installed, the RPM gage hasn't worked, it just makes spuratic movements. I ended up cutting those three wires anyway, theres' nothing wrong with that right? Since the RPM gage doesn't work, I may be able to use those wires for something else?

[Cary and Don]

If you have cruise control, you might not have any now.  Our cruise control uses something similar.

Don and Cary