CRASH BAR
On Valentine's Day, 2001, I got a call that my storage area had been broken into and the motorhome damaged.  As it turned out, they had bashed the roll-up door with some kind of vehicle and smashed the ladder up against the fiberglass, fracturing it under the paint and went under the coach enough to smash the license plate up underneath the valence panel.. I don't believe they actually went into the storage area as nothing else seemed to be touched.  After the break-in, I made up a "crash bar" that goes almost up against the inside of the roll-up door and locks into the receiver on the rear of the coach.  Hopefully, if they try that again, it will hold the door back enough that the motorhome does not get hit as well as leave some nice damage on THEIR car instead and they will not be able to get into the storage area.

INSTALLED ALARM LED BY DOOR
After the break-in, I decided to add a couple of things to try to deter them if they DO get into the storage area.  Hopefully, these will also help in a campground.  I used a flasher LED from Fry’s.  Installed in the vinyl trim strip on the left side of the door next to the handle.  It's wired to the +12V that is available at the Intellitec battery switch panel next to the door just inside the coach.  Although the LED has an internal current limiting resistor built in,  I added a 1200 ohm resistor so the LED draws only about 5 ma when it flashes.  In addition, I made up a warning decal and put that on the side window.  Maybe it will help a little..

INSTALLED OUTSIDE 20 AMP OUTLETS
To do this, it was necessary to run two, 12/2 with ground wires from the rear fuse box to the outside storage compartment.  This was done by snaking the wire through the existing chaise on the left side of the coach (inside) and then through the floor under the stove to get to the compartment.  I installed two 20 amp breakers in the fuse box and 20 amp plugs in the compartment.  Since these receptacles are after the transfer switch, they are connected to both sides of the incoming 220 line or to each side of the generator, depending on the source of the AC voltage.

MODIFIED ENGINE DRAFT TUBE
As originally supplied, the draft tube from the engine is above the frame rail on the passenger side of the coach.  This results in a pretty oily frame rail as well as leading to clogging of the intercooler with oily dirt.  There supposedly was a service bulletin on this from Caterpillar that lowered it below the frame rail somehow but Houston Freightliner knew nothing about it so I decided to fix it myself.  I added a “in line trap” piece of PVC obtained from Home Depot.  I cut the end off at an angle to create a draft when moving down the road.  The inside diameter of the original draft hose is 1 inch.  The OD of the PVC trap is about 1 1/16.  A clamp holds it in place in the hose.  The trap shape just clears the frame rail and the end is now about 3 inches below the frame rail.

INSTALLED QUICK DISCONNECT FOR PROPANE
When dry camped, it seemed that the batteries would not hold up as long as I would have expected.  I checked the parasitic current draw and found that almost 1 amp was being drawn from the batteries by the propane solenoid mounted on the tank.  To address this, I installed a female quick disconnect plumbed into the propane line that goes through the side compartment up to the refrigerator on the right side of the coach.  I bought a new high volume regulator and 5 feet of hose and installed the male part of the quick disconnect on the end of the hose.  Now when we dry camp, we can run the refrigerator off an extra 20 pound propane bottle and save over 20 amp hours of battery power per day.  The external bottle and regulator will supply enough propane to run all the gas appliances including the generator if need be.  Nice back-up.  Incidentally, the whole setup cost me $35.00!  (I had the bottle)  UPDATE:  Originally, we would take the batteries down about 50% in two days.  Using the external bottle, we recently went 5 days before they were at 50%.  I ran the refrigerator on the 20 pound bottle (in pretty moderate weather) for 6 days and had over half a bottle left.

INSTALLED FURNACE CONTROL SWITCH BY BED
This switch is in the thermostat control line and allows the furnace to be turned on or off from the bed.  In this manner, we can sleep cool in the winter but turn the furnace on in the morning before getting up.  The wire for this is 18/2 that was snaked through the chaise inside the coach from the furnace to the rear power compartment where the switch was placed on the outside of the lower cabinet.
 
 

INSTALLED SEWER HOSE CARRIER UNDER COACH
For this carrier, I used perforated PVC drain pipe purchased from Home Depot and secured it up under the coach just ahead of the sewer dump compartment.  The pipe was mounted using two long hose clamps and situated with the holes down to allow drainage.  The cap is a 4 inch PVC pipe cap with a plug.  The other end has a closed pipe cap glued on to seal it.  As you can see, the sewer coupling just fits inside the cap and the cover holds it all in.  I painted the pipe flat black to blend in. I have used this for several years on other rigs and it works out very well.

MODIFICATION TO ENGINE GRILLE FOR COOLING
This was a warranty recall by Damon to improve engine cooling while towing a car.  The modification was performed by Allstate RV (formerly Burditt) in Spring, TX.  If I had it to do over, I would NOT let them modify the grille until I had overheating problems.  The original looked MUCH better in my opinion.
 
 

INSTALLED SIDE TURN INDICATOR LAMPS
I installed dual bulb clearance lamps and wired them as clearance/turn lamps.  I mounted the lamps just at the top rear of the fiberglass front wheel housing.  The lamps were originally designed to ground to the frame through the mounting screws.  Since this is a fiberglass body, and I needed access to both power and ground, I soldered in a ground wire to the frame of the lamps.  The wiring to the coach is very straightforward; the new “ground” wire from the lamp goes to the hot side of the turn signal filament (white wire) of the front turn signal.  The “+” lead from the lamp goes to the hot side of the running or parking lamp (green wire).  Now, when the turn signals are turned on and the running lamps are off (headlights or parking lights off), the added clearance lamp flashes in synch with them.  Under this condition, the lamp is grounded through the parking lamp filament.  When the running lamps are on, the clearance lamp is on as well, getting its ground through the turn signal filament.  When the turn signal is turned on now, the clearance lamp flashes out of synch with the turn signal.  In this condition, ground is obtained through the turn signal filament when the turn signal is in the off mode.

FIXED CB ANTENNA AND INSTALLED CB RADIO and AMATEUR 2 METER RIG
The factory installed CB antenna had an infinite SWR.  I fixed that by adding a piece of braid for a counterpoise to the inside of the mount where the bolts came through the fiberglass.  The braid now hangs down under the cover on the driver’s side.  After the addition of the braid, the SWR was 1.5 to 1.  I then installed a small GE CB radio with the bracket mounted in front of the transmission control console on the wall.  It is wired such that it is on with the ignition switch.  I also installed my Azden two meter rig under the shelf over the driver’s seat using one of the screws that was originally there.  I hid the wires in the gap of the trim panel and snaked them to the lamp that is located near the radio where I picked up power.  I know, I know, I was supposed to go all the way to the battery with the wiring but this thing only draws about 4 amps on transmit and works fine this way... and it was MUCH easier.  I used a Larson NMO2/70BCO dual band antenna mounted on a Maxrad BMMB34 mirror mount mounted to the fiberglass on the right side of the coach, just behind the windshield. The Larson antenna is a co-linear antenna with an air wound coil in the middle.  The antenna can be bent double and will return to its original shape.  Just the ticket to combat the trees in some campgrounds.  On a recent trip to Florida the antenna performed very well.  I was able to hit repeaters on the normal fringe areas and simplex operation was very satisfactory.

INSTALLED RESISTOR IN VENT HOOD FAN CIRCUIT
The fan in the vent hood over the cook top would literally scream and there was a vibration that I was not able to remove.  I fixed the problem by putting a 3.15 ohm 20 watt resistor in series with the fan to slow it a bit.  Seems to work fine now and the vibration is gone.
 
 
 

INSTALLED WATER PRESSURE SURGE TANK
I installed a 2.2 gallon pre-charged water reserve tank under the kitchen sink.  The tank came from Home Depot and was very inexpensive.  The pressure is set for 20 PSI.  I put a PEX “T” in the cold water line up to the kitchen sink and ran PEX tubing to the tank.  This stopped the surging of the water pump and we can now wash hands or flush the toilet several times without the water pump even turning on.
 

INSTALLED DIGITAL VOLT METER ON DASH
This is a “Lascar” model EMV 1200 purchased from Allied Electronics. It is a self powered (only has two wires) 3 digit digital volt meter.  This is a slick little voltmeter that mounts using one small hole.  The wires run out through the center of the mounting stud.  It is wired to the radio power lead which comes directly from the Intellitec controller.  In this manner, it reads the voltage on the lighting buss in the coach.  If the coach is plugged in and the house batteries are disconnected, it reads converter output voltage.  When dry camping, it reads the voltage on the house batteries.  Great for telling the charge status of the batteries as we drive or when we are dry camping.

INSTALLED STATPOWER PROwatt 800 INVERTER
This inverter will deliver 1000 watts continuously and a 2000 watt surge.  Used #4 gauge welding cable and a TRACE 110 amp “T” series fuse.  The unit is wired directly to the coach batteries.  The inverter was installed in the front of the coach right behind the center console for a short run to the coach batteries.  A 14/3 extension cord for the 115 volts was snaked through the cable chaise on the left side of the coach to the bedroom front power panel where it is connected to the “receptacle” and the “GFI” circuits with a transfer relay.  The inverter drives the relay coil such that if the inverter is on, the receptacle and GFI circuits are powered from the inverter.  If the inverter is off, (and the relay in its NC position) the circuits are tied to their original 15 amp breakers.  I also added an indicator lamp on the dash to indicate when the inverter is on and a master disconnect switch on the console.   These circuits power all the 115 volt outlets in the coach as well as the refrigerator.  When under way, we use the inverter and run the fridge on 110.  It is very nice to start out in the morning and fire up the coffee pot without having to start the generator.  1000 watts will also run the toaster (not at the same time as the coffee pot) for that english muffin while I drive!  I also installed an accessory 12 volt cigarette style outlet using a #12 wire and a 30 amp fuse from the coach battery.  This allows relatively high power devices (like a Peltier icebox) to be run while on the road.

INSTALLED ANTI THEFT SWITCH
This switch is a 30 amp ignition switch mounted on the cover over the transmission controller.  The switch is in series with the “battery power” lead to the Allison controller.  With the switch off, the engine starter will not engage.  If the engine is running, turning the switch off illuminates the “DO NOT SHIFT” lamp on the dash and the controller is turned off.  There is no way to shift the transmission out of neutral with the switch off.  You can set the fast idle and remove the anti-theft key and not worry about the coach being driven away.  Doing this sets a “23 12” code in the Allison computer but everything works normally.  When we park the coach, I remove the key and the engine can't even be started.

INSTALLED UNDER COUNTER LIGHTING
My wife complained that the counter area was a little too dark.  To address this, I used a three halogen lamp kit purchased from Home Depot for $15.00.  The lights are installed in the kitchen area on either side of the vent hood.  I used the supplied 120 V transformer so we have to either be plugged in or use the inverter to make them work.  They are running on 11.5 volts off the transformer. If I had wired them to the house 12V supply, they would have seen nearly 14 volts when plugged in and I was worried about bulb life.
 

ADDED HEATER OUTLET DUCT
When heating the coach up from a cold start, the furnace would “limit” once or twice and the burner would shut off while the fan continued to run.  The burner would re-light in a minute or so and the heating would resume.  It turned out that this was caused by the high temp limit switch shutting the burner off.  The duct flanges were very poorly mounted to the floor and allowed a LOT of heat to escape.  This hot air was being drawn right back into the furnace inlet and causing the high temperature limit switch to open.  In addition, there was excess hose that was kinked restricting the airflow.  After repairing the heater flanges where they mounted to the floor of the coach and trimming off the excess hose, I added an additional duct to the furnace to increase airflow.  The outlet was installed into the left side of the drop down panel below the sofa.  It turned out that the required 4” hole was already in the wood behind the fabric.  All I had to do was cut the fabric and install the duct.  Hydroflame sent me the new flange (at no charge) to mount in the unused hole in the front of the furnace.  After the addition, the furnace will bring the coach up to temperature without ever limiting.  The bedroom also heats MUCH better now as well.

BUILT DRAWERS FOR BASEMENT STORAGE AREA
I built and installed two drawers per side for under coach storage.  Each drawer goes half-way across the coach and is heavy enough to store canned goods.  They slide on wooden runners lubricated with silicone spray.  In the first picture, you can see the block underneath that serves as a stop when you pull the drawer out and down to load or unload.  As you can see, they are great for that extra stuff from the pantry.
 

INSTALLED STAINLESS SCREWS IN FREEZER
The original screws and washers in the Norcold freezer compartment were rusting so I replaced them with stainless steel allen head screws and stainless washers obtained from Home Depot.
 
 
 

30 AMP POWER CORD
Most places we go only have 30 amp service.  In fact, a 50 amp RV connector is in reality 50 amp, 220 volt service.  In most RV applications, the second pole of the 220 line is used to run just the rear AC.  With most adapters, if you hook a 50 amp cord to 30 amp service the rear AC will not run.  I made up a cord using a standard 30 amp plug and a Marino connector.  I wired the two hot poles together inside the Marino plug so that now, I can run either the front or the rear AC when hooked up to 30 Amp service.  As I recall, the connector is a Marino 6364CRNS.  Although these connectors are expensive, the convenience of not having to handle the 50 amp cord is worth it to me.

ADDED AC COMPRESSOR LED
I wired the LED from the switched side of the thermostatic switch on the evaporator to ground.  In this way, the LED is lit whenever the compressor is running.  The LED is mounted just to the left of the HVAC control panel on the dash.  I used a 560 ohm dropping resistor in the positive lead from the thermostatic switch, and mounted it right near the connection to the thermostat.  That way, should the added wire ever short for some reason, all the current that can be delivered is about .020 amps.
 

ADDED OUTLET FOR VOLTAGE AND POLARITY MONITORS
Added a second duplex outlet for the line voltage meter and the polarity monitor.  The receptacle is wired to one of the existing plugs (below the cabinet) and is fused with a 6 amp fuse.  Now the voltage and polarity can be easily monitored and the polarity can be checked after plugging in the house cord (by looking through the window)  before ever getting back in the coach.
 
 

MODIFIED ENGINE AIR INLET
The inlet hose fell off the flange of the air intake box because it folded in from the clamp pressure on the thin flange.  I went to Home Depot and got a water drain like you would use in a flower bed.  The back of it was just under 5 ¾ inches and JUST fit into the original hose flange on the air intake box.  This makes it MUCH stronger.  While I had the box off the motorhome, I noticed that the hole through the side of the motorhome didn’t even come close to lining up with the air inlet in the box.  I cut out about 1 inch more of the plastic box to open up the air path.  Previously, the filter minder would jump almost to the top with a new filter.  Now it reads significantly lower.  Guess I was starving the engine for air all along.  Incidentally, the hose connection to the engine air filter was reinforced the same way after it folded in on itself as well.

REINFORCED STORAGE DOOR STRUT MOUNTS
The gas struts for the storage doors were originally mounted using long screws through the foot of the brace and into the door.  The leverage was such that all of the screws had loosened at one time or another and had to continually be tightened.  Several had actually pulled completely out over time.  To address this problem, I made up some 3" X 4" .062, T6 aluminum plates.  The corners were drilled to accept #10 X 3/4 sheet metal screws.  I cleaned the surfaces well and then put white silicone caulk as a glue between the plate and the inside of the door.  I screwed the plates to the door and then drilled the plate with the appropriate drill to accept the same screws and mounted the foot of the struts to the aluminum plates.  The strut mounts are MUCH stronger now.

ADDED MINERAL OIL TO BATTERIES
I had read about the oil that they sell to add to your batteries to stop or minimize the corrosion around them.  I did some research and it seems that Edison used oil in his original batteries that were used along the railroads.  In fact, they say you can still find the bottles along the tracks some places.  Anyway, I did some research on the stuff that is being sold today and found the patents for it.  Turns out that it is primarily mineral oil with a few other additives, primarily for color.  I made a call to a friend of mine who is a chemist to see if there would be any reaction between sulfuric acid and mineral oil.  He said that not only is mineral oil just fine in a battery, HE had used it for just that many years ago while working as a mechanic in his Dad's truck shop.  He said that it worked great to stop the corrosion and outgassing so based on this information (and Edison's experience!) I added 4 ounces of USP grade Mineral Oil (intestinal lubricant!) to each cell in my 6 volt, deep cycle batteries.  That amount seems to result in a blanket about 1/8 - 1/4 inch thick.  If you take a cell cover off now while the batteries are charging, there are little tiny bubbles on the top of the oil.  No more big popping bubbles to carry sulfuric acid out of the cells.  We'll see how it works!  I will report back in a few months.

April 2003 UPDATE:
It has now been over one year since I first added the mineral oil to the batteries.  I have had to add a very small amount of water one time in that last year.  I recently did a load test on the batteries and I cannot tell that there is any capacity loss at all in the last year.  I don't believe that the addition of mineral oil has in any way harmed the batteries and it has certainly eliminated the corrosion that was occurring on the terminals.  I will definitely use the oil in any deep cycle batteries I purchase in the future.

April 2004 UPDATE:
Its now been over two years since I added the oil to the first set of batteries.   I recently did another load test and I can't tell that the batteries are degraded at all.  When I added the second set of batteries, (read about it here) it made it a bit more difficult to accurately measure capacity on the first set but overall, the battery bank is performing fine.  I certainly have no complaints relative to the addition of the oil to the cells.  Again, I have added water the the cells only once in the last year.

January 2007 UPDATE:
We were getting ready to be on the road for about 6 months and a lot of that will be dry camping so I replaced all 4 of the coach batteries with Interstate golf cart batteries from Sam's Club.  I didn't want to take a chance of having battery problems on the road and the coach batteries are a BEAR to replace.  The new batteries got 4 ounces of mineral oil in each cell before they were even installed.  Two of the batteries I replaced were 7 years old and had the mineral oil in them for 5 years.  The other two were about 4 years old and had the oil the whole time.  When I removed the old batteries there was ZERO corrosion anywhere including the battery trays themselves.  I am a big believer in the mineral oil in deep cycle batteries.

INSTALLED SEDIMENT FILTER IN WATER LINE FROM TANK
Originally there was not enough room to put an inlet filter directly on the inlet to the water pump.  I installed a filter in the line from the tank to the pump.  I got a regular filter designed to screw on the inlet of the pump and got the correct fitting to go on the ½ inch pipe thread outlet of the filter to allow it to go in the ½ inch ID hose that runs from the tank to the pump.  With the filter installed that way, I can separate the filter housing and immerse the pump side of the filter in antifreeze solution to winterize the coach water system as well.
 

INSTALLED POSITIVE AWNING LOCK
On the trip to the west coast, we got into a heck of a storm and the awning tried to open while going down the road.  I replaced the A&E awning cam lock with a new one but I was not satisfied that would positively prevent the awning from opening under similar conditions.  I developed a positive lock for the awning by using parts readily available from Home Depot.  Later, I went back and replaced the end cap with a new one (from MarksRV) that contains a new pawl assembly so I now have a fully functional A&E lock as well as the TWO accessory locks.  I don't think the awning will be unintentionally coming open anymore.

There are two things that prevent the A&E awning from unrolling while going down the highway.  The primary thing is the locking pawl that is located in the right end cap of the awning.  This consists of an aluminum disk and a pawl that engages it.  The other thing that prevents the awning from unrolling is the tension on the springs located in both ends of the awning tube.  Notice that the arms being locked against the rig have nothing to do with the awning staying rolled up.  The awning WILL unroll with the arms still tight against the rig.

To address the unintentional unrolling, I used a heavy-duty picture hanger, a screen door catch spring, a stainless steel hose clamp, a couple of S hooks and 6 feet of chain for each end of the awning.  Although it sounds a bit like a "Rube Goldburg" setup, the picture shows that it looks very neat and clean on the rig and performs very well.  In addition, I have had several very positive comments on it.  The picture hanger is clamped to the end cap on the awning using the stainless hose clamp and the door stop spring goes between the ring on the hanger and the foot of the upper brace for the awning.  The whole lock can be installed or removed from the ground and it is impossible for the awning to open with it in place.  The installation was very straightforward.

First, mark the rivet that holds on the end cap that is on the outside when the awning is in the up and locked position.  This is so you will know where to install the picture hanger in the next step.  Then open the awning and clamp the heavy duty picture hanger to the end cap using the stainless steel clamp as shown in the second picture.  The hanger is placed with its bottom end just above the head of the outside rivet that you marked earlier.  This prevents it from slipping around the end cap when the spring pulls down on it.  Tightening the stainless steel hose clamp forms the tab on the hanger around the curvature of the end cap.  After the clamp is tightened, use a screwdriver and bend the hanger away from the clamp enough to allow the S hook to go through the opening.

This is how the spring assembly hooks to the hanger.  In the first picture, the awning is in the down position for clarity.  The spring is normally removed and installed with the awning in the rolled up position.  As shown in the second picture, the spring is easily installed from the ground by hooking the S hook over the top of the awning rod and holding it in place on the rod by pulling down on the chain while you raise it and hook it on the picture hanger.
 
 

To hook the bottom S hook to the rafter foot, pull down on the spring with the awning rod as shown in the first picture.  I have found that selecting a chain length that results in pulling the spring so that is about half compressed seems to very firmly lock the awning in the closed position.  As a test, if you unlock the factory front travel lock and try to open the awning now, the spring absorbs the shock and the awning will not open.  I think the spring is a good idea to prevent undue strain on the system in the event the front lock fails.  This is really a very simple modification to perform and the total price is around $15.00!

UPDATE:  I later added clear vinyl tubing over the chains to prevent marring of the arms from the chain vibrating in the wind while going down the highway.

INSTALLED AIR FILTER FOR DASH AIR CONDITIONER
While in Wal-Mart, I spotted some air filters designed to go in floor vents to prevent junk from falling into the openings.  It turned out they were the perfect size to cover the air intake on the dash AC.  This will prevent cat or dog hair from getting into the evaporator.  The filter is just tucked in front of the opening and the airflow holds it up against the opening.  It doesn't seem to have a significant effect on air flow so we will see how it works out long-term.
 

INSTALLED NEW SHOWER DOOR SWEEP
The old sweep had failed and Damon could no longer get them,  Seems the supplier that made my shower door had gone out of business.  I went to the hardware store and got a standard vinyl shower door sweep and cut off half of the top ridge so it would slide in the groove that the end screw goes into.  The dimensions came out perfectly and the door is once again sealed.  The picture shows the top ridge trimmed to fit the slot.
 
 

INSTALLED WARNING LIGHT & SWITCH FOR BRAKE BUDDY
I wanted to be able to activate and monitor the Brake Buddy in the Toad from the driver’s seat of the motorhome.  I ran two wires in the wire chase on the driver’s side of the coach from the back of the coach to the dash of the motorhome.  I then installed a four wire flat connector on a harness from the motorhome to connect to a matching connector on the Liberty.  I used two of the wires on the connector for the ground connection and used one wire for the brake light indication and one for activation of the Brake Buddy remotely.  The brake indication wire goes to a red indicator lamp installed in the dash of the motorhome just above the switch bank.  The other end of this wire is connected directly to the brake lamp switch in the Jeep.  The other wire in the harness is connected to the “hot” wire in the harness that connects from the brake-away switch on the Jeep to the Brake Buddy.  It connects to a push button mounted on the front face of the transmission console in the motorhome.  Now, when I press the button, the Brake Buddy is activated and the lamp on the dash comes on.  When the Brake Buddy activates itself the lamp comes on as well.

Note that the warning lamp is connected to the brake switch in the Liberty, NOT to the Brake Buddy itself.  Not only is that simpler but should the Brake Buddy fail to completely release the brakes (which has NEVER happened), I will see the indication and stop long before any damage to the brakes can occur.

INSTALLED MOUNT FOR AMATEUR RADIO HF ANTENNA
I made a mount for my amateur HF antenna out of 1.5 inch wide by 1/4 inch thick 6061-T6 aluminum.  The mount is bolted to the rear awning support rafter.  In this manner, it can be used with the awning against the coach or with the awning out and the arm staked down against the ground.  I use a Hustler bumper mount antenna with the Hustler Spider to allow the use of three resonators so three bands can be used without taking down the antennas.  To hook it up, I mount the Hustler and then run a piece of RG-8X to the front of the coach where it connects to a similar piece of coax that runs through a feedthru into the coach.

I have checked the SWR with this rig and it is typically very close to 1:1 at resonance and under 1.6:1 at the band edges.  The antenna seems to play very well and I am back on HF when we are camped.

ADDED SECOND SET OF GOLF CART BATTERIES
I added a second set of golf cart batteries to the coach by building a battery box out of 1/8 inch thick, 2 inch angle steel.  The box is bolted to the frame, using heavy steel brackets, behind the original pair of batteries and the batteries are wired in parallel with the original set to deliver 440 amp hours of capacity.  The addition is very nice when we dry camp.  I used the mineral oil blanket in these batteries as well.  To install the new box, I placed it on a floor jack and jacked it up into place.  This worked very well considering the batteries weigh about 62 pounds each.  Yes, I have heard the the old story that you shouldn't mix old and new batteries but in my experience, as long as they are the same chemistry, there is no problem with it.  I have done it several times before and it has worked just fine.  In this case, the original batteries were installed in 2000 so they are three years old.  The new ones and the old play very happily together so I am happy with the setup.

ADDED LINK 10 BATTERY MONITOR
I installed a Link 10 battery monitor in the panel above the previously installed AC circuit voltage and polarity monitor.  The Link 10 uses a 500 amp shunt installed in the negative lead of the battery for all the current measurements.  I ran four conductor, 16 gauge twisted cable (speaker wiring) for the connections to the batteries and the shunt.  I made a new battery ground cable and interconnecting cable from #1 welding cable and soldered on the appropriate copper terminals.  In the first picture, you can see the quiescent power consumption of the coach.  Not bad!

Here's a shot of the shunt and its wiring and the voltage sense lead that is fused and connects directly to the battery positive terminal.  The third picture is the back of the meter and how the wiring was run in the cabinet.

The Link 10 meter has two DC voltage inputs.  One is the line going to the battery for voltage measurement and the other is the supply that runs the meter itself.  This second supply is not a precision source and draws about 50 milliamperes when the meter is on.  I connected this line to the power line for the 12 volt lamp located in the cabinet below the meter.  In this manner, when the master switch for the house batteries is off, the meter draws essentially nothing from the batteries.  The only disadvantage of this is that you have to reset the meter when you power up the coach but all the settings like battery amp hours and charge efficiency are retained.  This system really works very well for keeping track of the batteries while dry camping.

These pictures show some current data that I found interesting.  The first is the current from the Magnetek converter after I had been plugged in for a while.  It started out putting over 40 amps into the batteries and here, had dropped to about 29 amps.  The batteries were down about 10% at this time.  The second shot is with the coach back on battery power and shows the current drawn by the inverter to run the refrigerator on electricity.  The last shot shows the current drawn to run a small "Snark" vacuum cleaner on 110 VAC.
 

INSTALLED ICOM IC-208H AMATEUR RADIO
The old Azden I had in Princess had become somewhat unreliable and it didn't have tone capability so it was time to get something new.  I looked for a long time and finally decided on the dual band Icom IC-208H.  It is a neat little rig that puts out 55 watts on VHF and 50 on UHF and of course, has full tone capability.  The installation was easy since the antenna I had originally installed was a dual band antenna.  I checked the SWR and it was under 2:1 on both bands.  I installed the control head on the dash and the transmitter portion on the side of the console under the dash.  This made it easy to get to power (this thing needs a 20 amp circuit!) and the antenna.  Since it comes with the separation cable, it was a relatively easy installation.  For a speaker, I used a Motorola communications speaker I picked up at the TRW swapmeet a while back.  I think we are all set for VHF and UHF now.

ADDED REMOTE SWITCH FOR INVERTER
The furnace control switch mentioned above worked so well that I wanted to install a similar switch to control the inverter when we dry camp.  The inverter draws about 1.5 amps when on because it is running the "instant start" feature in the TV's as well as other 110 volt parasitic loads.  That's a lot of power consumption if allowed to run all night.  To address this, I ran a 24 gauge wire pair through the wire chaise into the bedroom and mounted a switch just below the headboard of the bed to control the inverter.  The wires are connected in parallel with the front inverter control switch.  Now the inverter can be turned on or off from the bedroom.  Nice for watching TV when we dry camp.

INSTALLED SATELLITE WIRING
I had DirecTV installed at the house and it was time to wire Princess so we could use it on the road.  I ran RG-6 cable from the cabinet over the driver's position, across and down the right inside window trim, across the firewall and out to the coach battery area.  I Installed a bracket there for connection to the cable to the dish.  I also installed another RG-6 cable (the white one) over to the audio/video switch box in the DVD/VCR cabinet.  In addition, I cleaned up all the wiring for the audio/video switch center that was just sitting on top of the DVD/VCR.  I removed the lid of the DVD/VCR and drilled holes so the switch box would be permanently mounted in place.  It appears that the chassis of the satellite receiver is not isolated from ground so I could get a "tingle" off the box so I ran a three wire extension cord across and into the compartment for the satellite receiver which took care of the grounding problem.  I made up a PVC mount for my second satellite dish, complete with 4 inch levelers, to assure easy alignment of the dish in the campsite.  The switch box now allows selection of satellite, antenna or DVD/VCR for either TV as well as allowing the DVD/VCR to record either the satellite or antenna.  Now, when we travel, we can use a receiver from the home, and have satellite TV on the road.

Interesting note; the satellite receiver draws almost the same amount of power whether it is turned on or off.  If running it on an inverter, it would be a good idea to unplug it when not being used to minimize the battery drain.

INSTALLED LINE AMPLIFIER FOR SATELLITE TV
The signal from the satellite receiver had a lot of noise (snow in the picture) when the receiver was used in the motorhome.  It was fine at home so I suspected it was due to signal loss through the signal switch in the motorhome.  I picked up a TV R.F. amplifier at the TRW Swap Meet and installed it between the receiver and the switch.  This DRAMATICALLY improved the picture.  It is crystal clear now on both front and back TV.

INSTALLED OLYMPIAN WAVE 6 CATALYTIC HEATER
We really enjoy dry camping in cooler weather and at least here in California, even in the summer, camping in the mountains (our favorite) can get pretty chilly in the evening.  I had done quite a bit of  reading about the catalytic heaters and there are certainly two sides to the discussion.  There are those that say they are very dangerous because of carbon monoxide and those that say they are perfectly safe if you use them correctly.  Since we never sleep with any kind of heater on, I decided it was a safe thing to do so here's how I installed the Olympian Wave 6 in Princess.

The biggest challenge was to get the low pressure propane to the heater.  Our Onan generator is run on low pressure propane vapor so there was a 1/2 inch black iron pipe right under the right front of the motorhome to deliver fuel to the generator.  As it turns out, there was a coupling in the pipe, just behind the connection for the generator. I removed the coupling and put in a black iron "T".  The side port of the "T" was reduced down to 1/4 inch pipe thread and a 5 foot hose was connected there and run up to the front of the firewall.  Then I drilled a hole through the firewall and put through a 1/4 inch brass pipe nipple and connected the hose to it through a street "L" and used a 1/2 inch pipe clamp to secure it to the firewall. 

Inside the motorhome, I used a quick disconnect that came with a shut-off valve (Mr. Heater P/N F276181) that I picked up at Camping World.  By using this, I could disconnect the heater when we were not using it.  I connected the heater to the quick disconnect with a piece of welding hose I had a welding shop make up.  All in all it makes for a very nice installation and the heater works VERY well.  I would HIGHLY recommend one of these heaters if you remember the required safety precautions.  It is very important to remember that these heaters consume oxygen so you MUST have a couple of windows cracked to supply make-up air!!

INSTALLED FAN INSIDE NORCOLD REFRIGERATOR
I have used 12 volt computer fans inside the box of my RV refrigerators before and it really helped make the cooling more even throughout the box.  Normally, I have wired the fan ACROSS (that’s correct, across) the door switch.  For those that are not familiar with this wiring, the reason it works is that the current drawn by the fan is MUCH less than the current required to light the lamp.  Therefore, with the fan across the switch, when the door is closed, the fan is effectively in series with the lamp and runs.  When the door opens, the switch shorts out the fan, connecting one side of the lamp to ground and the lamp lights.  The main reason I did it this way is so that with the door open, I’m not stirring up the cold air and mixing it with warm air from the room.
 
I wanted to install one in my Norcold 982IM but the door switch was not readily accessible.  In looking at the schematic of the control board, I noticed that the fan control is a negative terminal.  That got me to wondering if the lamp is at 12 volts all the time and the control board grounds one end of the lamp in response to the door switch.  

I pulled the cover off the lamp and sure enough, that’s how it works.  I was able to wire the positive terminal of the fan to the innermost terminal on the lamp and the ground was picked up on the cooling fins.  The fan is mounted to the fins with a pair of hitch pin clips from Lowe's.  The ground wire is connected to the fins with a spring clip.  Now with the door open the fan is off and with the door closed, it runs.  If someone wanted the fan on all the time, just use the outermost lamp terminal.  It’s at +12 all the time. 

The only fly in the ointment is that the +12 is supplied to the lamp at all times… even with the box turned off.  I decided this wasn’t a problem for me since if I have power on in the coach, I am typically using the refrigerator.  If this was a problem, a tiny toggle switch could be installed near the fan to turn it off when desired.

BUILT BATTERY FILLER
While not really a modification to the motorhome, this tool turned out to be so helpful that I thought I would include it here.  I have had a long standing problem filling the cells in the back batteries of the motorhome because they are very hard to see.  I built this tool to help with that job.  The body is made out of some kind of poly stuff that was VERY gummy.  If I do another one, I'll use delrin instead. It machines much better.

I machined the body (the part that goes into the battery fill port) so it is a snug fit.  That way it holds itself in place while you fill it.  The hole through the center is just under 1/4 inch so the tubing is a press fit into it.  The squeeze bottle came from Wally World and is a press fit into the tubing.  The screw is a stainless 6-32 that is set at 1.125 inches below the flange.  That sets the water level at 1/8 inch below the split ring... just the way they want it.

To use the tool, I connect a voltmeter between the stainless screw and ground.  Fill the bottle with distilled water and turn the bottle upside down and gently squeeze to dispense the water into the cell.  That way, as soon as the meter shows a voltage, you know the acid is touching the screw and is at the correct level.  Of course the voltage is dependent on the cell you are in since you are actually measuring from that cell to ground but it is a VERY definite rise once the acid hits the screw.  It took me about 5 minutes to fill all the cells in my four batteries using this tool and I KNOW they are at the correct level.

More to follow.... I'm sure!