It’s gonna be really good to be able to use that word again without any political overtones
We arrived in Galveston to begin our Covid-Hunkering, but only just barely. For the last 100 miles or so, I was noticing an issue with a key RV WHERE YET system. And when I say “KEY,” I do so NOT tongue in cheek, which might refer to the Blender, or the Musical horn. Those ARE important, but Air Brakes trump all!
WARNING! MECHANICAL and PHILOSOPHICAL notes follow!!
I always try to provide a little background to mechanical stories – some may think I have deep and wide mechanical expertise – the truth is I am only slightly ahead of most of our readers, and climbing a steep learning curve with the gracious help of the Senior Bluebird Cabal.
The bus’ brake system is exactly the kind found in large trucks – Compressed air is used to apply the huge brakes sufficiently to stop the bus, and for safety there are redundant air systems. These are isolated from each other and from the general air system (used for slightly less imPOtent activities like honking the horn, inflating the air-ride suspension, etc.) by check valves. These maintain pressure in the brake systems long enough to safely stop the bus in case of a major leak in the “general” air system or air compressor failure.
I noticed as we approached Galveston, that one of the redundant brake systems was NOT maintaining pressure. I stopped at a wayside rest to consider the problem. I heard no air leaking, and the second brake system WAS properly pressurized and operational, so this was not a catastrophic problem. But, this needed to be resolved as soon as possible. I knew we would be in Galveston for several weeks, so I’d have ample time to figure out the problem and either fix it myself or find a mechanic to do so. We continued on, watching the air gauges like a hawk, in case the second system started to exhibit issues.
Once firmly ensconced in Galveston, I crawled under the bus to investigate, tracing fully the air system until I COMPLETELY understood all the tubes and pipes and valves and ALL of their operational nuances and, according to Liz, to get purposely and THOROUGHLY covered in grease. I concluded the ONLY possible issue was the check valve for the first system – not opening to allow pressure IN. Knowing this and FIXING this are two different things. The valve itself is a standard item, used in every truck, and was shortly acquired from the local NAPA store.
The problem: Access to the old valve. And not only that, removing the old valve and associated fittings virtually welded together by 40 years of operation! I spent a FULL DAY under the bus, contorted to get wrenches in, and ultimately the valve was sitting in my hand; though I could NOT separate it from the bushing and tee on either side no matter how hard I wrenched.
Unfortunately, several brass fittings were damaged in the process; and these were made of previously mentioned “unobtanium” (NOT directly replaceable). I won’t go into all the gory detail – simply needed to reconfigure the various connections – kinda like reassembling a jigsaw puzzle out of different pieces yet coming out to the same result.
Fortunately, the guy behind the counter at the local NAPA store was SUPER UNDERSTANDING; going back into the warehouse multiple times and coming out with various combinations of fittings for me to try. He wasn’t masked (I was, why wouldn’t he, just to make his customer more comfortable? IDK…same reason Waffle House doesn’t have outdoor seating, I guess…), so I had to talk to him from three steps back from the counter, in a non-confrontational way, but eventually we got ‘er done!!!
The FINAL challenge in this reconfiguration was a real teaching moment. The original brake system used copper tubes, and with the various new combinations of fittings, I was not sure I could get the old copper to line up and connect to the new fittings perfectly. If not quite perfect, air would definitely leak. They do make Nylon Brake lines that I could use for a complete re-plumbing project… This would require a LOT more work from me, in very tight, hard-to-reach areas under the bus, but might be my only alternative.
I wasn’t sure about replacing metal with plastic for something as imPOtent as brakes (and Liz was feeling VERY nervous about that!), so I posted a question online for the Bluebird Brain Trust/Old Farts. I got two useful answers:
- EVERY SINGLE truck today uses DOT-Approved nylon lines and push-fittings, so how could this be dangerous?
Not QUITE convinced, until online guru#1 said:
- “That old copper will be as hard as a woodpecker’s beak (I THINK he said “beak”)…nylon is the way to go…”
Anyway, armed with PLAN A (rejiggered fittings but close enuf for continued use of existing copper) and PLAN B (replace the whole thing with new Nylon Lines), I had a way forward. And LOTS of time, as we are planning to stay in Galveston for at least a couple months. Indeed, no actual forward movement possible until the brakes work!
For the REST OF THE STORY…a future post!!