Sorry, when I said air up I meant the tyres. All four would easily take an hour from sand driving soft psi, the left rear had the exhaust outlet aiming straight at you. An attachment that actually clipped on to and stayed on the valve without me holding it would have been very welcome. Any suggestions?!?
If you mean a knurled knob on the right side of the steering column, it is a hand throttle. But you have to use the foot throttle to set the speed and then you can hold it by twisting the knob. Mine was a fire truck and you might want to raise the idle to run the water pump. Might also be useful when inflating tires or using air tools.
OK, thanks guys. That makes sense. Got the box off today and the chassis looks pretty good with very light rust only in a few places. I do not think we will sandblast, have pressure washer coming tomorrow for a few hours of blasting. That and trying to figure out what I cut that has made the truck run rough.