Generator Redux – A Few Final Adjustments

We had been planning a run to Florida for the Arcadia Bus Rally in December. So, the pressure was on to get the generator completed in time for our intended departure around December 19. I think I got it complete sometime during the first week of December.

At the same time I was reworking my generator and bay, the hydraulic levelers decided to go south. Suddenly, one day the left rear cylinder would not retract! So, I set the generator project aside and called TS at Equalizer Systems. They were helpful (eventually) but it took several days to determine that one of the switches on the control panel had failed. Of course my entire system is obsolete and they don’t sell replacement parts unless you want to ‘upgrade’ to the latest generation – a very expensive option. Fortunately, I was able to find a used controller on the internet and quickly scooped it up. It was a different shape and had a different wiring harness, so I had to rewire the controller and remount it. After I got that done, the levelers worked fine and I could turn my attention back to the generator.

That little project set me back another week, so the schedule was getting very tight! I needed to get the genset up and running so I could do some PM on the bus and get it loaded. It takes a few days to get this thing ready for a trip. Well, it all worked out and we departed late morning on our planned day and a huge winter storm chased us halfway across the country. The day after we went through Little Rock, AR they got 10 inches of snow!

We’ve already posted several times about that trip, so I’ll just say that, on the whole, the trip to Florida went great! The MightyBus ran like a champ (albeit slowly – see Throttle Fiasco in a previous posting) and the generator got a workout as well. We had few if any issues until just a few days before we got home.

One night in Georgia, the lights went out – no sorry that’s a song. One night in Georgia, just before we were to retire to bed, Wendy and I both smelled sulphur. I’d been running the generator for several hours, but we just immediately assumed it was propane that we smelled. So, I shut the refrigerator down and closed the valves on the tanks. The next morning, I went to start the generator and – nothing. The start battery was dead? That’s weird, because the start batt is supposed to get charged while the generator runs. So I went into Wal-Mart, bought a set of jumper cables and jump started the generator. I also turned the propane back on to cook some breakfast and we immediately smelled propane again – or so we thought. I shut it all down again and breakfast was completed in the microwave. So, we just kept the propane shut down for the rest of the trip and I had to jump start the generator when I needed to run it. I’d look into it when I got home.

Fast forward a week or so and we’re back home and I finally have some time to look into these problems! I decide to start with the generator start battery and discover that it has swelled to twice its normal size!? Did it freeze after it went dead? So I take it up to my battery guys and they immediately recognize a cooked battery. “How did you cook that battery?” I had no idea, but warranty doesn’t cover that and I’m out another $90 for a start battery.

When I get back home, I hook up the new batt and fire up the generator – whoa!!! The generator charging system is putting out 17 volts! That explains the cooked battery and (as someone gently pointed out to me on the bus forum) cooked batteries can smell a lot like propane! Hmmm…

Now, the old generator charging system was a rectifier and a magneto so that came along with the little Kubota when I built the new generator. However, when I called  TS they tell me that I can’t have both! One or the other but not both. Well, I know this is the way it was wired at the factory so I don’t know what to say about that. However, they were able to point out that there’s no adjustment and it either works or it doesn’t! So I either start replacing obsolete parts (if I can find them) or (as they said on Monty Python) do something completely different.

I decide that a dedicated charger wired into the generator output is the way to go so I head back to my battery store for a suitable charger. We find the perfect charger for the Optima battery and they even rewire it so I can plug it directly into my battery connection. Cool, now I just have to wire it in and I’m on the next problem. Not so fast! That new charger has ‘Start” button on it? What? That won’t work because I need a charger that requires no human intervention! So, I head for home empty-handed and decide to use an old 10 amp charger I have sitting in the shop.


It was a simple task to simply bypass the rectifier and magneto on the generator. So I add a breaker to my generator sub-panel and wire in a receptacle.  In this shot you can see the charger, the receptacle and the 12 volt leads exiting my inverter bay.  So, when the generator runs, the charger charges at an appropriate voltage and my battery should stay happy for a long time!  Of course, nothing is ever simple and I notice that even though the charger is Off, there’s a small parasitic load on the battery for a stupid LED!  I disconnect everything and give myself few days to think this over.

I probably could have solved this with a diode on the 12 volt lead, but I really don’t know much about diodes and besides I found the perfect little 120VAC relay at Grainger’s for $20. So, I open up the charger, wire the relay coil into the 120vac side and the contacts into the 12vdc side, close up the charger case and VOILA!  Problem solved.

I start looking for a propane leak next. Except, there isn’t any leak!  I mean I tried everything I could think of to run down a leak and found NADA!  No leak. I even pressurized the entire system, shut the tank valves and let it sit for 24 hours. When I came back – I still had pressure in the system. So, at this point, I have to conclude there was no propane leak. That sulphurus smell was me overcharging the start battery on the generator.  Moving on…


When I trashed the old generator control box, there was this nice hour meter in it. So I decided to use it for my new generator. I just cut the meter out of the box and using the same sheet metal screwed it to the roof of the gen. bay. The wires for it were already in the new control box so connecting it up was a cinch. I’ve got another one up in the house with the remote start.

I also noticed that the generator bay got super dirty on the Florida trip. Those air intake holes in the bottom of the bay are directly behind the right front steer tire.  So a lot of road grit, water and dust got thrown up into my new generator bay. This will not do!

So I took some leftover plywood and build a couple of vent doors.  I have included a few pictures of that project below.

IMG_4379 IMG_4380 IMG_4381

The last little job was to add a couple of cutoff switches. I wanted to be able to disconnect the generator start battery so I used a Blue Sea cutoff switch I had lying around in the shop. Since I had two of these switches, I decided to also install a cutoff for the 12 volt power to my slide- out room and the hydraulic leveler systems. Here’s a quick shot of those two in the inverter bay.


So, the Mighty Bus is ready for its next big adventure!  Where to I say?


One comment on “Generator Redux – A Few Final Adjustments

  1. Nice Job Jim. Nothing like keeping ahead of a storm lol. Do you have any kind of mud flap behind the steer tires? That would help as well, but i am guessing you dont run the gen set underway. Couldent a cat be trained to place and remove the panels? Love the cutout switches. For finding gas leaks i use a bottle of kids blow bubbles with a small paint brush. The sulphor smell was the give away. You wont ever forget that smell. Used to open boat bilges and have to jump back!!! Again, nice work, Hi to Wendy

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