Category Archives: Skoolie

Air (Part I)

One of the nice things about the bus is that it has an air system for the air brakes, which means that it has a compressor that runs off the engine with a mechanical pressure regulator and a dehydrator for the system, which doesn’t mean that it makes apple chips, but rather that it helps keep water from building up in the brake lines (which can be a big deal in the winter!). You might ask why this is a nice thing, since your car most likely gets along fine without such things.

Well, first, it offers the possibility of refilling tires if need be, or, if you like, any number of air-powered accessories, like tools (impact hammers/wrenches, drills, jacks, etc.), or an ‘air seat’ for the driver (highly over-rated from my experience on school buses that have them), or air suspension bags (to aid the shocks and smooth the ride), or to run air horns. However, one of the things that our bus didn’t have as part of its air system was an auxiliary tank.

Air brakes for a single unit vehicle only need one tank with three partitions. The first partition (wet tank) is the place where air is stored for future use, and to trap more of the moisture that might have made it through the dehydrator. The second partition feeds from the first tank and serves to provide air to the front brakes, and the third (also fed from the first) provides the air for the rear brakes. This is why, on a vehicle with air brakes, there are either two pressure gauges (one each for the second and third partitions) or a single pressure gauge with two differently colored needles, each indicating one of the two brake partitions. (Multi-unit vehicles with air brakes usually have a separate gauge for the trailer brake tanks.)

Now, some of the people on the Skoolie board had just tapped into the first tank for a ‘service’ air line for tools (or in a pinch, to hook a compressor to, in case the one on the engine failed), but it’s not something to tamper with if you want safe brakes. I wanted to be able to use an air line for tools, as well as run air horns, and have the possibility to upgrade to air suspension bags in the future if we decided we wanted it. In order to do this, we needed an auxiliary tank.

I found an auxiliary tank online that was a 20 gallon one that would fit alongside the air brake tank under the bus. While one might think that this would be a simple matter of running a line between that first partition of the brake tank over to the auxiliary tank, you can’t do that, because there is a maximum amount of time your air brake system can take to get up to “working pressure” of about 85 psi from starting with no pressure. If you hook a 20 gallon tank up to that first partition, you have to bring that whole storage area up to the 85 psi threshold within that minimum time, which just doesn’t work.

Air pressure valve, 85 psi on
Air pressure valve, 85 psi on

In order to get around this problem, I had to install a pressure valve in the line between the two tanks. This valve stays closed until the pressure in the brake tank partitions get up to about 90 psi, then opens, allowing the compressor’s air after that bring the whole system up to pressure over a longer period of time. One of the things that ends up happening here is that I have a lot more air available for my brakes when the system is up to pressure (120 psi), as the 20 gallon tank can feed air back to the brake tank as long as the system pressure is over 85 psi.

The pressure tank I got had a whole lot of ports, but none on what I wanted as the bottom (because of the placement of the ‘feet’ for attaching it), and one on what I wanted as the top, so I ended up having to support it from underneath, rather than bolting it directly to the floor. The location of this port to be facing down was important so that it could be used as a drain to get rid of excess moisture, and I did double-duty in putting in a pressure release valve in, so if the system over-pressured (150 psi +), it would let the excess pressure out and save other elements from stress. , but I could also manually activate it as a drain.

Bedrails can make good structural supports!
Bedrails can make good structural supports!
Building supports for the air tank
Building supports for the air tank

So, one port was the pressure relief valve, another was the air coming in from the brake tank, and, for now, only one port would be used for feeding up through the bus body to two air sounding devices. The first was a Leslie Supertyfon RS-3L that was originally installed on a Conrail Diesel locomotive that my father had acquired somewhere (more on this later). The other was an ‘air chime’ which, when used nautically ends up meaning an air horn, but in this case was the closest I could get to a steam whistle. It channels the compressed air through four different chime pipes, a rich sound compared to the air horn.

The next thing to do was to lift the tank into place, which is actually tougher than it sounds, as I was attaching it to the bottom of the floor and to the side of the bus’ ‘skin’ where it drops down.  In order to hold the tank in place, I decided to use a nice floor-jack and lift it, but this also was trickier than it sounds, as the tank was balanced just so and having the supports catch on the brake tank or the skin of the bus could cause it to tilt and slide off the jack.

Jacking the tank into place
Jacking the tank into place
Lifting the tank into place
Lifting the tank into place

 

 

 

 

 

 

The new tank and pressure regulator in place
The new tank and pressure regulator in place

 

To be continued (in Part II) …

 

And for a really nicely detailed explanation of air brake systems, look to this great Army informational film from 1967:

Buses and fuel

  On a bus-conversion board, I found a discussion on fuel tanks. Some buses have one, and reports of size varied from 40-100 gallons. Some buses come with two (seemingly of the same size) which vary from 30-100 gallons.  (It would be awesome to have two 100 gallon tanks … As it is, we have a 60 gallon tank.)  But perhaps more important for how far you can get on your tank(s) of fuel is your miles per gallon (mpg).
  As for mpg, actual mileage of fully converted buses (that people have reported) go from 3-16 or so (diesel).  Much of this seems to hinge on gearing and travel speed, but some is in the styles of buses, with ‘conventional’ or ‘long-nose’ chassis get better mpg than the ‘pushers’, which isn’t a surprise, as the nose is more aerodynamic than the ‘flat wall’ of the buses with the rear engine.  Even with the aerodynamic issues, buses lose out in mpg because, as Mr. Jake von Slattso nicely puts it, they’re steel skin over steel supports with more steel inside, all mounted on a true medium truck chassis. Plenty heavy, but plenty safe , and with lots of space. Ours, even with the low amount of travel it gets and the much higher amount of idling is getting about 12 mpg.
  In comparison, while most factory-made RVs are on lowered chassis to optimize head-space, and are built of wood, fiberglass, aluminum, and sometimes steel in order to reduce weight, they still seem to get between 2-16 mpg (diesel), with some of the newer hybrid engines hitting on that upper range.  But the structural stability of these is nowhere near that of a bus, and that is not even factoring in the large slide-outs that compromise the structure as well.
  So, when asked about (or confronted with a) “well, wouldn’t it make more sense to just buy an RV for better mileage?” or “don’t forget that all that weight you’re adding in tanks/walls/appliances/frippery will take away from your mileage!”, I have to take a deep breath and re-iterate that school buses are about the safest vehicles on the road.  And yes, while a lightly (or under-) loaded vehicle is likely to get better mileage than one that’s fully loaded, buses with air brakes stop better when loaded, and most buses are geared low enough that the added weight really doesn’t stress the engine too much. (One guy on the Skoolie board commented that he built Jacuzzis into his buses and the mileage didn’t vary at all whether the 8/10-person Jacuzzis were full of water or empty.
  We’re been exploring WVO (Waste Vegetable Oil) as a fuel source, in order to make the project more efficient in its mileage. Why WVO, you might ask? Well, most diesel engines will run on it with -no- modifications whatsoever (Apparently, there’s a type of fuel-lubricated rotary fuel pump on some engines that has an issue because the WVO is more viscous than diesel fuel). Major costs involved in the conversion are auxiliary fuel tanks, a fuel tank heater (WVO needs to be at about 160 degrees to flow like cold diesel), a flow switch/ electric valve and possibly new, corrosion-resistant fuel lines.
  There is a filtering/ settling process to actually get the WVO to be usable (though some don’t worry about this – which may or may not damage the injectors), but you end up with a cleaner burning fuel that smells like french fries (or probably in our case, wings).  There’s an outfit in Mississauga, Ontario that makes in-line pressure-driven centrifuges that would take water and particulates out of the WVO.
  I’ve asked on another board how the mileage with WVO compares with diesel, and it seems like WVO should give about 80% the power of diesel.  I’ve been toying with getting another tank to get 50-100 gallons worth of travel of our trips for just the labor and filters of processing out the sludge from the WVO – which will likely be well worth the savings at the pump, since many restaurants have to -pay- to have the stuff disposed of …

(Near) Winter Camping at Sprague Brook Park

  At the end of November of 2013, my son and I took our two dogs to do some near-winter camping at Sprague Brook Park in the south of Erie County.  We had never been to Sprague Brook, but it was suggested to us as a place that had ‘winter camping’.  It turns out that that means that the small loop of power campsites is open until November 31st, but the bigger loops of unpowered sites is already closed.  I was actually happy that the site would have power, since the bus doesn’t have a heating system.  I had thought that I would bring two small 1500W space heaters, which I figured would keep the bus warm.
Such a nice glow …
  I had just had the almost 3ft by 9inch plastic ‘School Bus’ signs removed and replaced with glass to let more light in, so it really changed how the bus was for driving (I was able to see the light above the intersection through the new window!  Conversely, the new windows provided a way to get the sun in your eyes …)  I also pulled out a couple of light fixtures to let us see in the evenings.  The first of these is a nice brass fixture that is reminiscent of a gas lamp that a previous owner put a little push-switch on.

I put this up on the wall in the ‘cabin’ area so we could see to eat and read in the facing bench seats.  I had some nice 40 watt amber bulbs, so I put them in and it gave the ‘cabin’ area a nice cozy glow.

The other fixture was a carriage lamp that I put up near the bunk, as our son likes to have a night-light.  I didn’t want anything really bright, since I dislike light while I’m trying to sleep, so I settled on a little 3 watt ‘flicker-flame’ bulb.  It seemed like it wouldn’t give much light, but at night when you’re trying to sleep, or get around, it gave off more than enough.
And you can just make it out despite the
fluorescents in the garage …
  We stocked up with firewood, a large, old, several gallon coffee tote full of very hot water, several gallons of drinking water, eggs, bacon, venison, bread, butter, onions, potatoes, coffee, hot cocoa, and some other sundries along with our sleeping bags, a cot (only one of the bunks was done), and warm hiking clothes.  Even with all that, we stopped by the EnglishPork Pie Company on our way to the site so that we would have some warm food in us while we set everything up.
  The trip was nice.  It started out on four lane & six lane highways, then to four lane roads, and then to nice winding two lane roads through small towns and over streams along water-worn cliff-side that showed the geology of the Devonian period.  But it was slower going, some slower traffic and stop lights holding us back a bit.   The pies turned out to be a good idea, as it got dark just as we got to the park, and it was a slow process of backing up and checking behind the bus, then adjusting the bus and backing it some more, and checking and adjusting again.
The bus, in situ, with the moon, just after parking …

 

  But our campsite was right across the loop from the washrooms and, it turned out, we were the only campers there that night.  We set up the extension cord to the 20 amp outlet and plugged in the heaters and the lights, though when both the heaters kicked on, the flicker-flame bulb wouldn’t light, but that wasn’t a big deal, as there were streetlights around the campsites.  These probably wouldn’t have been so bright when there were lots of leaves on the trees, but in November, they spread a lot of light around.  Luckily, our campsite was in amongst a good stand of white pines which tried to help.
  As the evening wore on, though, the heat that the engine gave us for the bus interior was wearing away, and even with the two space heaters, it was chilly.  The dogs really didn’t care, however, and were happy out on the lines that I tied to a nearby tree, as well as being in the bus.  Our husky decided that the bunk was for him.  The only downside of having the dogs was the accordion-style bus door, which can make it a bit more awkward to clip the lines on or off their collars, but we work it out, and get a fire started.
And this is what warm looked like in the morning.
  But our son breaks out a surprise that my wife sent – some candy.  We use the bread, some chocolate, and Mary Janes to make some tasty Toastite sandwiches, and we do some setting up and reading before bed.  Given how cold it is, I give our son my mummy bag (good down to 0 F when I got it years ago) and he opts to stay on the (for the moment novel) cot, and crawl into his sleeping bag on the bunk still in my clothes.  Luckily, this means I got the husky for extra warmth.
And here’s the bus at the site in the light …
  The morning was chill and quiet.  The temperature went down below freezing overnight, and in the light I discovered that the side door that I ran the extension cord through was kept slightly ajar by the cord, so there was a source of cold.  Of course, the bus is lacking a whole bunch of insulation at the moment, so it is easy to get cold.  Rerouting the cord in the light is a whole lot easier, and I got the cord through the back door.

 

  Looking out from our campsite, we can see that we’re on one of many terraces cut by the stream over time.  After we get dressed, we take the dogs for a walk down to the bottom of the valley, watching some deer make their way quietly off to the east and away from our noise.  Upon reaching Sprague Brook itself, we were a bit surprised at how small it was, but it was a fast-flowing stream with rocks of many different colors amidst sandy shoals, and the banks showed the past streambeds that had fallen into disuse when the stream’s erosion had undercut trees that had fallen and diverted the flow.  But, of course, this was still before breakfast, so, our curiosity sated, we walked back up to the bus.

 

  We started a fire and while it was getting to where I can cook on it, our son discovered a playground that was just at the edge of the campsites, so he goes and plays for a bit.  I got some coffee, hot chocolate, bacon, eggs, & potatoes cooked up for breakfast, and after eating, cleaned up and decided to go for a nice hike.  I ended up with both dogs on their leads, one on each hand, which actually balanced me out.  As we walked along the south side of the lip of the stream’s valley, we made some good time, and found another playground.  And another and another.
  The first leg of our five mile hike took us past four additional playgrounds before we got to the downstream bridge across Sprague Brook, and after crossing the bridge, we found another two.  The dogs and I weren’t as interested in these, but my son was, so each provided a delay to our hike, but not a really bad one.  The day was overcast and cool, but not too windy, so it was a great day for hiking.

 

A selection of the trails available.  Our site was in
that lower right loop.

 

  The trails at Sprague Brook were numerous, including an 8 mile loop along both banks of the stream, but we only hiked up to more direct way to the ‘overlook’ in hopes that we could see the bus which was essentially just across the valley, but we couldn’t.  There were just too many trees.  But our hike back was a bit more circuitous, following the lip of the valley to some interesting places where the roots of trees were the only things holding up the ground and making quite a drop.
The high point of our trip – altitude-wise.

 

Our son with the Brook  on one of the overhangs …
  We hiked about 5 linear miles and up and down some 600 feet (250 down, then 350 up and 350 down and 250 up), and got back none too soon, as it started a cold misty rain just as we got back to the campsite area, but it stopped again after 20 minutes or so.  The dogs loved the hike and were totally energetic for almost all of it, but they crashed when we got back to the bus, and just slept for hours.  We got another fire going and set up our dinner of bacon, venison, Phineas & Ferb mac & cheese, and potatoes & onions, topped off with candy-filled Toas tites for dessert.  (We earned it.)
  We read and stayed warm up in the cabin area, then, as getting ready for bed, I realized that the two heaters drew so much electricity from the 20 amp outlet that one of them wasn’t heating, just basically being a fan.  After that, I turned off the one that was putting out less heat, and we just had the one heater.  We slept in our clothes again, trying to keep our heads inside our sleeping bags, as the air was very chill. (Not surprising as the temperature got into the low 20’s (Fahrenheit) overnight.)

 

And lots and lots of terrain …
  When we got up in the morning, it was dreary.  We didn’t have enough wood for a breakfast fire, and our camp-stove ran out of gas, so we had cereal.  We took one more hike down to the stream, which was festooned with icicles on branches and sticks near its banks.  After that, we tiredly policed up our campsite and made our way in the bus out of the campsite and back home.   The trip was fine, and it was nice to get the bus up to temperature and get the bus comfortably warm.  Unpacking took a bit, but we learned a lot (like that we needed to bring more firewood and that I need to get the 30 AMP hookup working!).  Most of all though, our son (and the dogs) loved it and couldn’t wait to go again.