Mystery knob

[sdc53]

Got a knob I'm sure someone here knows the purpose of.  Under my dash on my 4107, there are 3 knobs.  The left one controls the left air wiper, the right one controls the right air wiper, and the center one does nothing on my bus.  What is it supposed to do?


Scott
'69 4107
Gladstone, OR

[B_K]

Maybe the sprayer for the washer ?
  BK 

[luvrbus]

Push that one don't turn  it is the washers

[sdc53]

Just came in for the night, but I'm pretty sure it turns like the others. I'll try pushing it next time I'm out.  My washer fluid tank in the bay under the drivers seat is toast anyways.  Are the washers air operated as well?


Scott
'69 4107
Gladstone, OR

[luvrbus]

The original was air that knob will turn but if original it pushes in to operate the washer 

[qayqayt]

Yes the window washer system is air operated.  If yours is toast, you can still get them new.  We got ours from Luke at US Coach.  The knob turns but you have to push it to activate it.

Bryan
Vancouver BC

[luvrbus]

I buy my washers from www.schoolbuspartsco.com  I find them to have the best buy on electric or the air air washer lots of different types and they have the parts to make the wet arm also

good luck