Before I got the floor finished and the seats in place, I had decided that I wanted to take the bus out for ‘exercise’.  The engine should be run about once a month, and the bus should be moved at least a little to make sure the diesel fuel sloshes about and doesn’t get set for algae and that the tires don’t ‘square’ from staying in one position too long.  (The ‘squaring’ comes form the wires in the radial tires sitting with so much weight on them in one place for a long time.)

  I had planned out a nice route from our house out to Broderick Park on Squaw Island Park by the Buffalo River, and wanted to take my wife, our son, and my mother-in-law.  It was to be the first real ‘passenger trip’ in the bus.  I used the old seat holes and threw two seats in place, right up front behind the driver’s seat, so it was mostly a big empty space, and somewhat loud when on the road, but I thought it would be fun.

The original entry steps.  Well, still the entry steps, but now a little different …

  It took a little bit to get my mother-in-law up the steps and into the bus.  She had some knee problems, and the bus only had two steps to get in.  At some level, that sounds simple, that she only had to make it up two steps, but those two steps (three, once you count the initial entry or the top step, depending) have to get you from ground level to 42 inches above, which is floor level.  And of course, I’d removed all the seats and the forward ‘wall’ and support railing when doing so.

  But with a couple of concrete blocks and a little wooden step, she got in, my wife and son got in, and we were ready to go.

  We got just outside the gate on our driveway, and I set the parking brake, went and locked up the gate, then got back in and we set off.  Once we had pulled onto the street, however, the air pressure, which normally sits right around 120-125 psi was plummeting, and there was a hissing sound. Well before we even got to the corner, the little ‘wig wag‘ arm let loose and was swinging (as it should have, right at about 80 psi).  I pulled over and set the parking brake so I could get out and try and suss out what was happening.

  Once the parking brake was set, the hissing stopped and the pressure started to rise again.  I took a quick look out and around, but couldn’t find a broken hose or leak, so when the pressure hit 125 again, we started off hoping that it was a fluke and we could go about our trip.

  It wasn’t a fluke.  Once again, the pressure dropped and I decided that we’d just go around the block and stop when necessary to get the air pressure back up, then go again.  Four stops later, we were back in the driveway, everyone was off the bus and I was trying to figure out what was wrong.

That’s not a shadow behind that front left bolt, that’s missing plastic that cracked out!

  With the wheels chocked and my wife taking the parking brake off while I was outside of the bus, I tracked the hissing to the rear axle, port side.  Climbing under, I found that a port pressure release (as I was to find its name later) was leaking.  I chocked the wheels and go into seeing what I could about the part.  Some scraped knuckles later I had it out and confirmed that it was not a seal, but rather a leak from cracked plastic.

  The port pressure release might look like a simple piece, but it’s tucked way up inside the frame rail with the bolts behind the that go through from the inside to the outside, which means that the nuts are almost inaccessible back behind the dual back tires.   Luckily, with a wrench jammed in on the bolt, one can still, with long arms, blindly work a ratchet to get the nut loose.

The nice, spacious workspace.  The detached lines are 1/2″ air lines that attach to the port pressure release.

   Now, by the time that I got the piece out, it was after hours when the parts department of the local dealership was closed.  I tried to do a parts search to figure out what kind of cost I would be looking for to fix it and get the bus going again, but without knowing the name of the part, that’s really tough.  So I had to wait for the dealership to open and take the part in and hope that they had it.

  While they didn’t have any of my exact make and model, they had an updated part that would meet the needed specs.  It turned out to be a simple part that cost only $22 and they just grabbed off the shelf, so I ended up getting two, just in case one of the others went in the same way.  Then I only had to put it back in.

At least the new one has more aerodynamic styling …

  That seems sort of simple, in that it’s just a matter of reattaching the relatively rigid air hoses back together, but of course, when I was taking them off they always wanted to screw back in because of the twisting of the plastic hose on the barbed fittings.  So when I started to screw them back in, they wanted to unscrew because I was twisting the hoses the other way.  I ended up spinning them in the direction against the threads for as many turns as I could manage and still keep control of their twisting, then fit them into the correct port on the port pressure release.  This ended up working fine, and the lines all went back together.

  Now, if you’re used to hydraulic brakes, like I was, you might find yourself a bit intimidated by working on air brakes, but it really is much easier.  See, in a hydraulic braking system at this point I’d have to open the line at the brake and pump on the brake pedal and force the fluid (and any air bubbles) out of the ~20 foot line to the back axle in order to make sure that the brakes would work safely.  But in an air brake system, all you have to do is start the engine up, build air pressure, chock the wheels, take off the parking brake, then get out and check around the reconnected lines for an air leak.  As it was, I had none, and with the engine already running, moved the bus forward, hit the brakes and the bus stopped perfectly.

  Yet another bus hurdle was overcome, and while no trip was taken, everything was okay, and I felt a lot more confident in the buses’ brakes.