The Distance: 1,154 miles, our least amount of movement in a month yet, obviously because we left the bus in the repair shop for three weeks.  Our total distance since the start of fulltime RVing at the beginning of the year: 6,556 miles.  Of course, if you count our plane flight to Hawaii…

The Places: Since leaving Death Valley on April 1st we had a night of mechanical failure induced stealth camping behind the gas station in Barstow, a short and unfortunate day in Joshua Tree National Park followed by a pleasant but expensive night at an RV Resort in Indio, and then three nights at Orange Grove RV Park in Bakersfield.  The bus then spent three weeks between two different repair shops, Bay Cities Diesel and Coach Maintenance Company, while we stayed at Rosemarie’s sister’s house, interspersed with a eight day trip to Hawaii.  Of the five nights on the road we had hookup sites for four and boondocked one.  So in terms of “cool RVing,” April was a bust, but in terms of family visits and vacations, it was a great month.

The Budget:  Totally, completely blew the budget due to the Hawaii trip.  Though we paid almost nothing for the plane tickets, it was the hotel and entertainment expenses accounted for 56% of our expenditures for this month, and resulted in us being about 75% over our planned monthly budget. Inexcusable and unsustainable.  We have resolved that come hell or high water we will be under budget in May and June to get our annual expenditure rate back on track.

The Drama:  So much of it.  Clearly, the complete loss of reverse gear on April Fool’s Day after a morning of dead battery stress and a failure to secure an RV spot in Joshua Tree makes that day the worst of the month.  Things improved from there even as The Big Kahuna’s battery charging worsened.  We stumbled into a perfect stealth camping site, put out the urgent word on Busnuts.com for a mechanic in the Bay Area, and nursed the bus all the way to San Francisco.

The Improvements:  Major power steering fluid leak fixed, reverse gear restored, and top gear (overdrive) transition significantly improved.  Those are big, though perhaps only the last one is an improvement since the first two were simply repairs of things that broke that month.

• January Report
• February Report
• March Report

Well this is the big reveal, the major upgrade we have been wanting ever since our scary downhill ride in Sedona.  Though now more prepared for such events, we experienced several more downhill runs, particularly leaving Joshua Tree and coming into Carmel Valley, that I can only categorize as “not fun.”   Such incidents increased our sense of urgency to improve Kahuna’s braking ability, and online research revealed that retrofitting an “engine brake” onto our Detroit Diesel engine is perfectly doable.  Thus, two weeks ago when we picked up the bus from Ted following the reverse gear repair, we made arrangements to come back for the Jake Brake install.

See that innocuous unlabeled switch to on the lower right? That will make all the difference next major downhill run.

Here is the gist of it: Trucks and buses are so heavy that their brakes are often insufficient to the task of slowing and stopping them on long steep downhill grades.  They become overheated and less effective.  Exhibit A: The Big Kahuna.  Thus you often see warning signs at the top of long downhills advising trucks of the percent grade, to check their brakes, and use low gears. Part of the problem is diesel engine mechanics; for most diesel engines, even when no fuel is applied, the full amount of air is sucked into the cylinder, compressed, and that energy applied to the crankshaft.

Door modification in progress to allow for the oversized valve covers.

In the late 50’s and early 60’s Clessie Cummins, of Cummins Diesel fame, developed a method of retrofitting a device on the rocker arms inside the engine that, when activated, would open the engine exhaust valves such that the compressed air is not applied to the crankshaft, but rather the energy is absorbed by the engine, effectively turning it into a brake.  Or as Ted explains it, it turns your engine into an air compressor.  We will be able to turn it on and hold our speed on even significant downhill runs without touching the brakes at all.  We just completed our test drive, and it works as advertised on the limited hills in this area, and exactly according to spec in terms of when it engages and how.  This major upgrade gives us a lot of peace of mind for our future runs through mountain areas.  The only down side is that the modifications required much larger valve covers, and one of them is so large that the rear doors do not close.  We will modify the doors with a professional looking bubble to accommodate the valve cover, but for now Ted just cut a clean rectangle out.

A bit Mad Max looking, innit?

Incidentally, engine brakes are often called Jake brakes because the first manufacturer/distributor was Jacobs Vehicle Systems.