What am I?!?!?!?

[Sc17842]

Does anyone know what this black knob is / does???
http://forum.prevostownersgroup.com/blob:http://forum.prevostownersgroup.com/593e96f9-6831-439a-af4d-974587d5c8bc

[Sc17842]

Picture of the knob

[Flatbroke]

Almost looks like a hand throttle control.

[Sc17842]

Traced the cable a bit and it goes through front fire wall, then across the front of the bus to the passenger side. I lose it after that. I don’t see that it’s moving anything, but does pull out about 6-8 inches.

[Sc17842]

You can see the cable when looking in grates just above the front bumper

[billbunch47]

Its the Liberty train horn push pull

[Sc17842]

Would it be mechanical ie. Cable pushes and pulls bellows, or is it something that the key has to be on to actuate??

[Joe Camper]

The control is mechanical and I dont think the ignition needs to be on. It is a train horn that would be even more defined to describe it as a steam whistle, it gives you more of a toot toot that an air horn blast. Great toy, grand babies love it.

[Pete]

Once you have air pressure, "pull" on it, the key does not need to be on. If it is working, it can be VERY loud.

[Sc17842]

Thanks everyone!!! I am traveling this week, but now very excited to get home, air up, and get to hear it. I never pulled it because I could not figure out what it did.