Back on the road! Engine brake field trials and battery charging enlightenment

We left Coach Maintenance Company having improved or resolved several critical issues: We got our desperately desired Jake engine brake installed, finally figured out exactly what was going on with the battery charging problem, tuned up the Detroit Diesel, straightened a storage compartment door frame, and eliminated our concerns about the low oil pressure indicator.  Though we road tested everything with Ted while at his shop, the true test, especially for the engine brake, would be a long ride with significant downhill runs.  Our trip to Glass Beach provided that in spades.

One of our many 7%+ downhill runs testing the Jake Brake

One of our many 7%+ downhill runs testing the Jake Brake

Engine Brake Trials:  We took CA State Route 20 from Williams to Fort Bragg (the California one, not the North Carolina one).  This is an unusually windy road, especially the downhill section from Willits to the coast, which gave us a pretty significant stress test on the new Jake Brake.  We hit numerous six and seven percent grades, a couple of eights, and one ten, with many of them requiring slow speeds to manage tight turns.  Along the way we learned the capabilities and limitations of the Jake Brake, along with how to best use it and when not to use it.  Bottom line: it’s a major assist but not a cure all.

Because of the idiosyncrasies of our transmission, the Jake only works in Direct and Overdrive (sort of the 2nd and 3rd gears).  It will hold the bus at any speed above 35 mph on a six percent grade without using the regular brakes at all, but steeper than that it needs them to assist.  Critically, when I drop the speed into the single digits, I need to be ready to disengage the Jake otherwise it might actually stall the engine completely.  Overall, I am very pleased to have this equipment; it made a huge difference coming down the Mendocino Range, and gives me a lot of comfort for the mountains to come.

It rained. We turned on the headlights.  The battery charged.  Son of a...

It rained. We turned on the headlights. The battery charged. Son of a…

Starter Battery Charging Problem: Solved, we think.  Most of you have probably read about our increasingly critical failure of engine to charge our batteries while driving, which has caused us to have to stop and use the Honda generator to charge them on several occasions.  I am not sure what caused this problem to get worse over the course of our travels, but we have a much greater understanding of our electrical set up now that we have spent hours with Ted at Coach Maintenance going over it.  In addition to cleaning and aligning the points on two critical relays, we also learned that the electrical regulator will not engage to charge the starter batteries until it senses a marginal electrical load.

Prior to The Big Kahuna’s conversion from a transit bus to a motorhome, there were several electrical loads on the system that no longer exist, such as passenger air blower assemblies.  It appears that the removal of these items has decreased the electrical load such that the system is not even engaging the charging circuits.  We now know how to monitor this via the recently identified mystery light on the dash panel, and our run west on CA-20 in mild drizzle accidentally taught us a work around to ensure that the electrical load sensor engages the charging circuit: turn on the head lights.  I’m not kidding, it was as simple as that.  We watched the charging failure light switching and off for the whole journey until we turned on the head lights, and then it stayed off. Crazy.  We suspect that some of the electrical work we had done in Florida or Texas may have removed some of the regular loading on the sensor circuit, but now we have a fix of sorts.

Proof that the engine brake worked: we arrived safe in Fort Bragg CA after running down the Mendocino Ridge

Proof that the engine brake worked: arrived safe in Fort Bragg CA after running down Mendocino Ridge

House battery charging via the Honda generator: When we first got the Honda EU2000i generator running back in Key West, we learned that our invertor placed an unusually high electrical demand on the system causing the little generator to trip off.  We just assumed that we would have to live with this limitation until we could install a modern controllable inverter with our house batteries.  During our full week stay at Coach Maintenance Company, however, we did some experimenting while hooked up via a standard extension cord to Ted’s 20 amp circuit.  We found that if we flipped all our circuit breakers to off, then turned on only the inverter battery charger, waited, then turned on the other circuits, we could keep the demand below 20 amps and not trip Ted’s breaker.

This got me thinking about doing the same thing with the Honda generator. Sure enough, it worked, barely.  As long as all the other breakers are off we can initiate power to the inverter; the Honda will flash the overload light sporadically for a minute or so until things calm down, and at that point I can turn on the other breakers, mainly the refrigerator.  But if I try and do this with the refrigerator breaker already on, it will trip overload circuit on the Honda.

I know this sounds minor and a bit down in the weeds, but this is huge for us.  For months we have operated with the assumption that, until we get a major electrical upgrade, we will not be able to charge our house battery system at all unless we are in a park with at least 30 amp electrical hook ups.  Now we have eliminated this limitation without changing anything but our procedures.  We can charge our house batteries with our little Honda OR at any of your houses with an electrical cord while we are parked in your driveways!  Yeah, us!