Generator Evaluation

Since the last owner stated that the generator was being "flaky" and shutting down I started the investigation on what might be wrong while it was out. He said it was an electrical problem. His generator guy had it working in the shop a couple of times before they pulled the plug on the repair and opted to replace. 

I found these sub standard crimp connectors on.

This brush block powering the stator of the generator (or not?) this connection also provided power to a second set of brushes on the same stator. First indication that this is not a low current application. Now add bad crimp connections and follow from there.

I also discovered what looked like some kind of ad hoc arrangement in the control panel of the Gen Set.  After looking at wiring schematics ti showed a 10 ohm resistor and a diode in this wire run.  So shoddy but not ad hoc. 

The solution was to Heat shrink the run and re secure in place.

Now the brush block feed is in better condition and awaiting a test.

Some spacers and new screws to hold everything in place and allow for the larger wiring loom. (the missing screw is broken off in the end case courtesy of the "Generator mechanic") Me thinks he should find a new hobby. Mechanic I see not, so far.

The next step I see is building a simple fuel system. Connecting a battery and fire it up to see what I get.

Gen Set retrival

  After winning a bin on eBay the next trick is to get the item you won. I just spent all day getting my (new to me) Generator set from a suburb of Nashville. 300 miles on the odometer on the van. Slightly less on the return trip ~10 miles due to a short cut I didn't know about on the way up but I still burnt more gas due to trying to keep up the speed to make it back for a boy scout meeting that was scheduled for Monday night. So all in all two tanks of gas in the E350 and a 500 lb generator on the trailer waiting to be transferred by what ever means I can muster into the storage of the Bus. Pictures to follow when I can take them. Lost two screws on the trip due to vibration but the load stayed in the middle of the trailer all the way home with no incident.

Generator won

OK no response form my gen set company BUT I did win a bid (again on eBay). Now to plan a 4 hour trip up to Nashville area for the pickup. This unit was used in a motor home and has 700 hours on it. the Generator part started going flaky on it when it was upgraded to a larger unit. So not without strings but at least one more of the big ticket things purchased at a reasonable price. ~1 sixth of full price.

Design notes

   I have amassed multiple pages of brain rumblings on design and random thoughts on systems and priorities.
Energy management first and foremost.
    Stove / Oven: At first I was under the impression that a commercial Motor home stove just wouldn't cut the mustard with this build. My wife wants to use this bus as a retirement cooking circuit vehicle. My mind said "all out galley" 4 gas burners and separate oven, maybe ovens. LP cook tops not a problem, easy to find. Dual and single LP ovens a little more tricky.  Electric is flat OUT no way to support an electric beast on battery. Now thinking on it How many times have you used all 4 burners on your stove? By the deposits on our home unit it is easy to see that we favor the large burner and one medium for most of everyday cooking. In that light a 3 burner LP unit with one large burner up front will suffice.
     Fridge:  Most motor homes use a gas absorption unit.  (Ammonia cycle) in short they use heat to make cold. The excess heat needs to be dealt with via vents or some other method Going over energy use of a standard high efficient refrigerator if the door isn't open all the time they run very little. So devise a latch to keep the doors from flying open during transit and use a home unit.
    Cooling: Most Motor homes use roof mounted AC units. This is the easy option and I could be running that direction.  But... If I get the Gen set from the refrigeration trailer it has plenty of guts to run a regular home unit. If I can find a 110v unit with large enough capacity I could plumb a Aircraft style duct work and central air the coach.
    Heat: I already explained to some extent on the previous posting. Both water and coach heat can be accomplished with hot water heat. Zoned with thermostats for each area via base board heat and controlled by valving opening the loop demanding heat. Dedicated loop for a water to water heat exchanger for Hot water for showers and washing dishes.  At one point in time I started to design a way to keep the fresh, Gray, and, Black water tanks from freezing in cold weather. Then it hit me put the Diesel burner (Wabasto) in the same bay as the tanks. The thermal spill from the unit will keep the bay and everything in it above freezing. Just have to insulate the bay from extreme cold.
  Plumbing: Speaking of extreme cold all plumbing lines need to have a low spot drain built in to the lines for purging all water for cold storage. The only exception is drain traps RV antifreeze will provide protection from freezing.
    Electricity:  Still in infant stage there. Depending on what is available the system will have 110v possibly 240v 12v or 24v battery banks plus inverter for 110v off grid and generator power.
    Lighting:  Everything I can I want to convert to LED lighting not only for the power consumption but the length of life on the units.  For $99.00 I can buy some neat solid track lights and if I can find replacement 12v led lamps to put in them I could run the entire system on 12v direct instead of using a 110v to 12v transformer.

How to heat

Even before I got to pick up the bus I bid and got a Webasto DBW-2020 heating unit.  This unit was designed to heat large Diesel engines in cold climates to keep from having cold starts.  The marine industry used these same units for potable hot water via a water to water heat exchanger and zoned heat in large boats. It puts out 80,000 BTUs. In my thoughts "this is a big boat" so why not?.  The unit uses a diesel fuel  burner to heat a water jacket of antifreeze mixture and pump it out to the engine block.  I have found 24V valves in both McMaster Carr and Granger that could open each heat loop circuit as needed on demand. This could be actuated by either a thermostat or a demand switch as for Hot Water at the galley sink for dishes or a shower.  Each loop would be actuated by a 24V solenoid double pole double throw so as not to allow back flow of electrons to activate other systems that are not demanding heat. 

Design stage

Now I have the shell. What do I do with it? On a recent boyscout outing even before I had the bus. I had a bid out on a different bus in VA. A little closer than the one I got but, the possibility of getting it put me into design mode.
  How do I develop a system to live "off the grid" for an extended period of time?
   Battery bank, with intelligent inverter/charger, Switching unit for ground / shore power that will tell whether 110v is available or not.  If 110v available charge batteries. If not available use batteries to provide 110v to the motor home.  Monitor battery voltage to determine state of charge and if it drops below a pre determined level start the generator and charge on 110v from it. Extend battery life by installation of solar panels on the rear roof to supplement battery storage.
  The big nuts to crack here are the cost of a Diesel generator, inverter, batteries, and solar panels.
Every Diesel gen set I have found so far has either been $6,000 or more for an RV unit or a small contractor grade air cooled running at 3600 rpm. The latter of them being loud and weak in power. The more expensive units run at 1800 rpm and are water cooled plus put out 6KW or more of power. Just what is needed to power 2 roof AC units.
  Just yesterday I had the epiphany of what else could be used. I have e-mails out to a company that has and overhauls clip on generator sets for over the road refrigeration trucks. I am hoping that they will not be priced out of my budget range for the build. By manufacturing standards these units have to be rated at 17KW perfect size not to small and not to big. Hopefully not to big as well in size.  Normally these generators are encased in a "frame" that hangs from bolts on the front of the trailer and contains a fuel cell and all the support structure for the engine and generator platform. Since I am using this in conjunction to the bus's original fuel system and intend to encase the unit under the bus I will not be using the frame. I do not have a dimension on the Generator set for space requirements yet.
  The inverter is also on the shopping list. I found that Xantrex had a recall on one of its units in August and called them to see if they had any rebuilt units for sale.  They told me No at this time but to call back in a month or so.

In The Begining

This is the interior as it started. I blocked off the seats to drop capacity below 16 passengers and get it out of the CDL category for the drive home.

Here is my 300 cu ft of basement. the rear bay will more than likely be used for water storage and management as well as heat systems to warm water and the coach

This is the Greasy pig of an engine that will have to come up to my engine standards before it goes on the road.

And this is the most important picture.  The bus's residing place AWAY from the house.

And so It begins

  The trip home was semi uneventful. Started out with the walk around on the bus while air pressure was building in the system. Inside the bus was warm in the Virginia countryside. First switch I went for was the air conditioning. The old owner said No, no air "Drat!!"  It's OK, open up the rear escape hatch for some flow through and turn on the drivers fan to circulate the air from the small driver's sliding window. Then I'm off first thing I notice is that the speedometer didn't even twitch.  Another problem to address. I don't even know the system. is it cable, is it tach, how does it work?
   Now I'm committed 40ft long of 96 inch wide of unknown, unfamiliar vehicle running through the VA country side with no way of knowing exactly how fast I am going. looking for my first stop, An advance auto parts store in Woodstock VA. Things to get: 1 OIL, 2 Seafoam, and 3 a funnel of sorts to administer the required fluids.  After checking the oil in the parking lot I put 3 quarts of the gallon of rotella 30W in the engine and stowed the remainder in the basement. Now to finish my boondoggling and get to the interstate for the trip home. By now the sun is starting to set. As it slowly got darker I turned on the marker lights and head lights.  The dash lights seemed weak so I turned them up and noticed the ammeter was out and the fuel gauge was as well. With a well placed precusson adjustment I got the fuel gauge light to come on and continued into the the night.
  When I picked up the bus it had around a 1/2 tank of fuel. My first fuel stop introduced the entire gallon of Seafoam to the tank along with $200.00 of #2 Diesel fuel. Labeling on the tank states that the capacity of the tank is 170 US Gallons. The gauge didn't reach 3/4 of a tank after the stop. The next fuel stop was inside the Atlanta city limits and was another $200.00 but it still has 1/2 tank when I got home.
  Adventures on the way consisted of a rest stop stop where the starter button was pushed 4 times before the engine would start.  Imagine the panic when you have no tools, have never worked on a Detroit diesel motor before and, are on the road in the middle of nowhere and the starter just spins. At this same stop the following also occurred.  My fuel gauge light refused to re illuminate and the air pressure,  (EVERY THING  runs on air) refused to build over 85 psi.  This was resolved by an adventure under the drivers floor in the spare tire compartment grabbing and wiggling some air lines/valves and pumping down the system with the brakes to allow the pump to sense a lower pressure. Then things began to cycle as they should.

   4:00 am found me backing into my drive with the bus home.  I wasn't right for two days after the 21 hour trip.