Assorted RV Modifications (and Hints) :

The Ideas here are ones I believe are unique, and each solved a problem for me. These notes may give you some ideas for fixups of your own. This is my third motorhome and I have made most of these changes on each one to make my life a little bit simpler.

RV  Idea 1.

Timer for Outside Lights:

I always add a 60 minute timer to control the outside patio  light. Too many times we forget to turn off the light and only notice it is still on the the next day. The mechanical timer is available from  most hardware stores in various timing ranges.  This solved the problem.  It is hooked in parallel with the existing patio light switch, which is left in place and is still useable.  The bulb was replaced with an LED lamp..

Timer for Outside light


RV Idea  2.

Screen Door Latch :

 A home made arrangement was made to allow opening  the screen door  without  opening the slide. This was fabricated from a stiff wire with an offset to push down on the outside latch handle from the inside. A bar was added across the screen just above the slide to allow easier closing of the door , also giving visitors somewhere to push against instead of the screen. The wire was once a buried cable marker  on the roadside with a small orange flag. The pushbar came from the frame of a collapsed  screen tent.

The first  shot shows the deails of the push bar, the upper wire support bushing and the red button to push down to unlatch the door. (The background is the Desert Mesa south of Ehrenberg Az)
Scrren door opener showing pushbar

This second shot shows the detail of the wire bending and the hole drilled in the white slide seal cover. A small grove was necessary in the slide itself to allow  full closure of the slide. I used a soldering iron to melt the required slot.
The stiff wire support at the pushbar was made from a wire holder, around a piece of rubber tubing. 

Screen door opener

  RV Idea 3.

Fixing Flexible Water Jugs:

We leave Ontario in early November, and have all systems winterized.  Water is in 5 gallon flexible water carriers, which can be  folded and stored  when empty. We keep them in the shower.  The problem is that folding usually results in pinhole leaks which according to Reliance Industries (the maufacturer) are not repairable.  I had tried many patching materials over the years but found only one method works. Use a glue gun. The carrier is made of polyethylene and so is the glue material. Use enough heat to soften the bag material enough to bond with the glue, and the patch will hold forever. Hobby glue guns are usually not hot enough.. But be careful not to melt an even bigger hole.

RV Idea 4.

Simple Parking Light Warning:
All my motorhomes have never had  a buzzer to alert me if the parking or headlights lights are left on after parking.

I made the following simple circuit,  consisting of  a 2000 ohm resistor in series with the negative wire of a 12 volt buzzer from Radio Shack. You can use either a mechanical buzzer or a piezo alarm. Resistor size is not critical, 1000, 2000 or 3300 ohms should work.

Connect the +12 volt wire from the buzzer to  a point that is live when the lights are on. I use the parking light. Connect to loose end of the resistor to ground. And then connect the mid point (where the resistor and -12 v. from the buzzer are connect together) to a source which is live when the key is on. That's all. Very simple.  Do you really need a drawing? 
Turn on the lights and buzzer sounds. Turn on the key with the lights on, then both sides of the buzzer are at the same potential. Buzzer goes silent. Turn on the key with lights off and 12 volts is only across the resistor, drawing a few milliamps but the buzzer remains silent. 

RV Idea 5.

6300 Series Power Converter:

This electrical mod is more complicated and can vary depending on the maufacturer of your RV's converter. Mine is a Parallax 6345 120/12 volt converter as shown in this photo.
Converter Nameplate
But the principle is the same for most.

Step 1.
  I put a 120 volt switch in the internal wire from the main breaker to the transformer.  It is usually black. Since I have plenty of regulated charging current available from solar, I wanted to prevent the unregulated built in  trickle charger from overcharging the batteries and boiling away the water whenever plugged into 120 service. Switch it off and you disable all charging.
 You can see the switch on the left in this next photo.

Converter front viewConverter Front View
After exploring the innards of the Converter , I wondered why the converter was rated at 45 amperes but the charger was averaging only 0.5 amperes. Maybe I could  fiddle the converter portion wiring to create a more robust charger and decrease generator run times if needed.

Step 2.
 Where were the converter amps going? I traced more wires and found that there were two power supplies inside. One small rectifier was used to energize the coil of a  transfer relay, and the other fed the charger and the converter. The transfer relay switched a portion of the 12 volt fuse bank off the battery when the RV was powered from 120 volt. The remainder of the fuses remained connected to the batteries, I assume as a sort of noise filter.

Panel 12 volt  Wiring

The next step was to connect both left and right  portions of the fuse panel together.  The New Heavy Red jumper wire with two yellow lugs is connected to the stud  with the blue wire coming from the transfer relay. It is sized to handle the full output of the converter.  It goes behind the fuse panel and connects at the back of the  panel directly behind the Screw Connector with the smaller red wire. At that location (behind) I first removed and taped the output wire that feeds from the trickle charger and parallels the two sections of the fuse panel (red , not visible in the photo).    Really simple, once you have traced the wiring. If you cannot do this yourself , get  someeone who can. I won't provide a diagram as every converter is slightly different and ratings are all over the map.

Now I had something. A real boost charger at little cost. Testing showed over 35 amperes initially, dropping slowly to about 30 amperes after 5 minutes or so.

What about over charging? I then added a timer identical to the one used for the patio light, in series with the wire from the small diode rectifier to the transfer relay coil. It times out in 60 minutes, shutting down the 30 ampere section and flipping back to trickle. The timer is located on the right side of the Panel front view photo. The brown lever arm made it easier to set and then view status from afar. The timer shuts down at whatever  time I preset. It also forces me to be around when running a boost charge that needs more than an hour.   ------------------------------------------------------------------

RV Idea 6

Onan Fuel Pump:
I had continuous problems with my Onan fuel pump. Failed several times. It might be a heat problem. It might be due to the gas tank seal filler cap being sealed and the pump cannot overcome the vacuum. No one knew. Onan replaced the carburetor. Failed again. Onan replaced the pump. Failed again. This was getting expensive. The location made it difficult to replace by myself.

Following a discussion with a 18 wheeler driver who mentioned he always adds a second fuel pump in series with the standard pump, just in case.  If one fails the other takes over. It gave me an idea.  I bought a replacement and found a place to install it in the front of the Generator compartment where it was easier to access. Leaving the old pump in place, I put the new pump #2 flow in series with the output of the old pump #1, and connected the output of pump #2 to the carburetor.  Then I electrically wired up the old and new pumps in parallel so they were both energized at the same time. (It seems there is a solenoid in the old pump which must be energized to allow through flow to the new pump). It has worked perfectly ever since..
But if it does fail, I can now replace it myself.

Here is the photo Of my placement of the second fuel pump.
Onan Fuel Pump #2 Location
 It is a little crude and shows the signs of years of bouncing on gravel backroads. There is not much choice of placement. I do have to lift the pump slightly to check oil level, but so far twice a year has been sufficient. With 360 watts solar,  I only put about 10hours a year on the generator, running it monthly to flow fuel through the carburetor and keep it out of the shop.
RV Idea 7

Water Heater Temperature Control.

Water and Propane saving are at the top of my list for extending boondocking periods. We allowed 3/4 gallon of fresh water per person per day when living on the boat. During our first years RVing  we attempted to meet these numbers. The shower was the biggest user. It needed lots of propane if left on all day and wasted good water just geting the temperature adjusted.. We soon learned to only heat the tank  if  needed for showers. That  saved propane, but water was still going down the drain while adjusting the temperature. Ok, so we then caught the initial water from the shower head in a bucket.  That saved some water.

But the real problem was the tank was too hot and it needed  cold water to make it comfortable to shower.
I bought an indoor outdoor thermometer and tucked the sensor on the tank inside the insulation. The readout was placed where it was visible inside the rig.  Now we heat the tank to 100F (you pick your own setting),  and then shut down the water heater. We no longer have any need to fiddle with the tap mixture. Problem solved.


RV Idea 8.

Buddy Heater:

This is more a suggestion than a mod, but is perhaps something of a new idea for most. The small Buddy Propane Heaters will only run on the green 1lb bottles for 3 hours at full output, and maybe 6 hours at half output. But when run on pilot alone will run for over 40 hours. In our RV, the pilot flame alone will raise and hold  the temperature inside about 15F above outside , enough to keep us comfortable on evenings, and cool days. It is like having a 300 to 400 watt heater that does not need electricity. Works for tent campers also.


RV Idea 9.

Towing Car with Automatic Transmission :

 In keeping with the theme of showing ideas which have not been seen elsewhere I must mention that in spite of what you read about not beeing able to tow most automatic transmission vehicles, you can. Just leave the engine running, and tow anywhere. This allows the lube pump to circulate and the engine cooling to dissipate the transmission heat.  

RV Idea 10.

Backing with Towed Vehicle attached:

Most literature warns against trying to back a motorhome with Toad attached.     After towing for several years I realized that as long as backing straight I could move a fair distance before the car would jackknife. The problem was knowing when the car was getting out of control.  By the time it was visible in either mirror, it was too late.  To solve the problem I  drew lines showing the straight back outline of the car on the backup monitor. If the car drifts towards the outline then move the top of the steering wheel towards that edge. It will correct itself and you will be able to continue backing. As long as it is kept straight backing can continue.

  This led me to develop a procedure for turning around. Find a place where the road makes a "T". Approach the "T" and make the turn and go until the auto is centered straight behind.  Now backup across the "T" using the technique above.  Now you can leave via the road you entered .  

More to come......
73 de VE3LGS
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