Good Sam RV Travel Guide & Campground Directory

Mark...My Words

Hi, everyone!

Welcome to summer and another great year of RVing. I hope you are out there enjoying all the wonderful RVing and camping opportunities this great country offers. Keep those questions coming!


Hi, Mark,

As we  are aware, when disconnecting a battery, one should disconnect the negative side first, then the positive, and reverse that order when reconnecting. However, how does it work when there are two 12-volt batteries connected in parallel? Which battery would you disconnect the ground from first? Would you disconnect the negative on the battery that the coach negative cable is connected to first, followed by that same battery’s positive cable? Then disconnect the ground from the second battery followed by the positive?

Just curious. Harv

Hi, Harv,

Disconnect both grounds first. It doesn’t really matter which battery you start with, but do both ground terminals before you start on the + sides to avoid shorting out the + side by getting a tool between the + terminal and the frame.



I’m resurrecting an older Coleman unit, circa 1980, and it needs some wiring help. I would like to

add a 12-volt auxiliary battery to the trailer (this trailer receives its 12 volts strictly from the tow vehicle originally) through the auxiliary 12-volt pigtail on the factory trailer harness. I would like to be able to charge the trailer battery off of the tow vehicle while driving, but I am afraid of burning up the wires either on the tow vehicle or the trailer. The real question is whether I can safely charge the trailer battery off of the tow vehicle while driving without burning up the wiring, especially if there is a large draw to recharge the trailer battery. Does this setup require me to run a heavy-gauge wire from the tow vehicle battery, or will the factory wires/harness suffice? Any thoughts, suggestions, or modifications you can recommend would be appreciated.


Hi, Chris,

Adding a battery to your rig is a good idea, but just be sure you put it in a place where it will have some ventilation to prevent the buildup of hydrogen gas, which can go boom in a big way. Also, you must secure the battery so that it won’t bounce around. The charge current from the tow vehicle is regulated by the voltage differential from the RV battery to the alternator. The smaller the wire, the more voltage drop there is and the less current. Because of this, even with a fairly discharged camper battery, the wire won’t overheat, but smaller-gauge wire will reduce the charge current down to almost nothing. Best bet if you want to get at least 10A of charge current back there would be to run either 10ga or 8ga stranded wire all the way. If you use the factory harness, it ought to have at least a 12ga conductor in it. For +12V, run heavier wire from vehicle alternator or isolator to the receptacle on the back of the tow vehicle and also internal in the trailer from harness to new battery to minimize voltage drop.


Hey, Mark,

Could you discuss the pros and cons of doing an axle flip on a 5-W, which results in gaining 3-4 inches clearance from your truck bed ?  A friend gave me one of those brass fittings that allows you to fill a 16oz propane bottle from a larger bottle.  However, no instructions were included and I can't make it work.  Can you explain the process? 

Thanks, Ron.

Hi, Ron,

Flipping the axles is a common way to raise the 5ver to accommodate a taller tow vehicle. It will gain you around 3-5 inches of increased hitch height. The job should only be done by a competent shop, as new spring perches must be welded onto the axle. You can't simply “flip them over” as the axles are designed with a built-in bow to provide for proper toe-in and camber. Most trailer service places can do the job. About the only disadvantages will be the need for an additional step at the entry door and a slightly raised center of gravity on the rig. These mods don’t usually adversely affect either tire wear or handling.

The bottle filler is a mixed blessing, in my opinion. To use it, you attach it to your large tank and then screw the small disposable cylinder onto it. Then you must invert the large tank so as to feed only liquid propane to the small cylinder. Open the valve and some gas will be transferred to the smaller tank. I have played with one of these refilling fittings and attempted to refill a number of cylinders. I have found that you typically don't get a complete gas charge into the little tank. About half-full seems to be the average, and what's worse, many of the little disposable tanks will fail to seal properly after refilling and can leak gas. For that reason, you should never store refilled disposable cylinders in any compartment or enclosed area. Plainly labeled on all disposable cylinders is a warning that they cannot be transported or shipped if refilled. That's because the dispensing fitting valves weren't designed for repeated use, and most will leak after several refilling cycles.



I recently put a new regulator on the propane tanks. It seemed to work fine, but then I installed a newer Suburban furnace, and when it kicks on, all the pilot lights to the stove and water heater go out. Even the stove top burner dips low. I picked the regulator up in the bargain bin at the local hardware and wonder if I have bought the wrong one. If they are all the same, do you think I can adjust it without taking the rig to an RV dealer?


Hi, Robert,

In order to adjust a propane regulator, you must use a manometer, not a common test item in most folks’ toolbox.  Plus, most new regulators are sealed, and no adjustment is possible by the end user. It’s not a good idea to try to adjust one, as too much pressure in the system can damage appliances or cause a fire. That propane symptom you  describe can be indicative of a defective regulator. However, it’s also possible that the regulator you bought is designed for a low-flow rate requirement, and your furnace is exceeding it. Either way, you really should consider replacing it with a new regulator, preferably one designed and UL-listed for RV use. Items like this that are critical to your safety should not be purchased used or by looking for the cheapest deal. A defective regulator can potentially kill you or destroy your RV. When it comes to parts like these, I always get the best (new!) one I can find and shop the bargain bins for other, less critical items!


Hi, Mark,

We have just traded a trailer of moderate height for a 12-foot-high fifth-wheel. On our first night out, we scratched the rig on low branches. The air conditioner housing extends 15 inches above the 12-foot roof, giving a maximum height of 13 feet, 3 inches. That means we need at least 13.5 feet clearance. Minimum highway clearance is 14 feet. We think campgrounds should adopt the same standard. We talked with a campground worker about tree trimming. He measured the lowest branch height overhanging the road near where we were standing. It was 12 feet. He thought that was plenty of clearance. Many campgrounds probably believe the same thing. We would like to know if our rubberized roof is more vulnerable to branch damage than other types. Has anyone ever had a roof damaged by trees, and, if so, how did you handle it? We would be especially interested in reports about our type of roof. Our local RV repair shop said something interesting: Campgrounds have a legal obligation to provide sufficient clearance on roads. If you damage your RV backing into a site you’ve been assigned to and you backed into the site correctly (in the official site parking area, not over by the picnic table), they are obligated to repair the  damage. Is this true? Supposedly, they assign you a site with suitable clearance, but we doubt any campground check-in has information on the height of branches over each site.

Thanks, Albert and Dinah.

Hi, Albert and Dinah ,

As RVs get taller, this sort of challenge becomes more common. Many campgrounds were designed years ago when a 16-foot Aristocrat camping trailer was a big RV! You are right to be concerned about your rubber roof. It is susceptible to damage from low-hanging branches and may be torn or holed by any sharp object. Never take chances. The only one who can prevent damage to your rig is you. Whenever possible, arrive before dark if the park is unfamiliar, and don’t be in a hurry to get to your site. If in doubt, look carefully before driving under spots that may be too low. If you are in a campground, stop and contact the manager when you encounter a low-clearance spot in the park. Although most campgrounds try to keep trees trimmed, some may have neglected the task. Parks generally try to keep roads and sites accessible, but they are not responsible for making sure that your rig will fit. As operator of your vehicle, it is your responsibility to avoid obstacles and tree branches.



Last October we were in central Illinois just as the corn crops were being cut and harvested. As a result, millions of Asian lady beetles suddenly found themselves without food or shelter, and they began looking for places to spend the winter. Hundreds found their way into our motorhome. We removed many, but we continue to find a few when it is warm and sunny. Internet information suggests physical removal is preferred to chemical treatment and that prevention of infiltration is necessary to keep them out. It appears that a major opening exists on the rear of the refrigerator/freezer cabinet on the outer wall. The removable service panel is built to provide ventilation and shed rain but not insects. Would it create problems to attempt to fit a screen on the inside of this access panel?

Thanks, Larry and Cathy.

Hi, Larry and Cathy,

I played host to a colony of ants once, and it took months of dedicated effort to evict them. Yes, denial of access is often the best answer to controlling pests. I suggest using standard window screen to exclude the critters. You can make a custom frame for the screen, or simply cut the screen to fit inside the access door and attach it with a little silicone adhesive around the  perimeter. Also, you may want to do a screen treatment on the fridge roof vent as well, as most are screened with coarse mesh hardware cloth only to exclude mice and birds. Make sure you keep the screen clean to prevent any air-flow restriction.


Mark Nemeth has been involved with all things RV for more than ten years, including almost 5 years on the road as a fulltimer. Nowadays, Mark is parked for a while and works on staff for the Escapees RV club as technical advisor, consumer affairs director, and instructor in the Escapees RVer's Boot Camp program.

Founded in 1978, the Escapees RV Club provides a total support network for RVers that includes a wide variety of opportunities for fun, adventure, and education. CHAPTERS There are 51 chapters across the U.S., Canada, and Mexico that offer local luncheons and rallies within 150 miles of home. Everyone is welcome to attend. HOPs Theme–related outings and adventures held across the country. ESCAPADES Five–day events, Escapades offer over 60 seminars and workshops to educate, entertain, and enhance the fun and use of RVs. PARKS Our RV park system offers short–term, long–term, and home–base parking options. MAIL SERVICE The best mail–forwarding service in the country. Members can personalize their mail delivery receiving only the mail they want when they want. PLUS MUCH MORE! A complete listing of all Escapees events, and a comprehensive list of member benefits are found at

Escapees RV ClubSome content previously printed in Escapees magazine, published by the Escapees RV Club. All material provided by Mark Nemeth, Escapees Magazine Technical Advisor and Boot Camp Instructor. For more information about the Escapees RV Club, please visit or call 888–757–2582.

Woodalls subscribers can save $10 on a new Escapees membership! For more information, visit the Escapees website.

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Please remember, material will be edited. Because of the large volume of material and correspondence submitted, individual replies will not be possible, nor can we acknowledge receipt of your material. Selected questions will be answered in future issues of the Woodall's/CampingLife Navigator newsletter in the Mark, My Words column.

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