Technical Inquiries: September 2002

September 2002

Fuel Concerns

Q: Although I don’t use my motorhome constantly, I do use it on a regular basis. However, there are times when it may be parked for a month or two between trips.

When I return from a trip, I fill the fuel tank and add a fuel stabilizer so that the coach will be ready for the next trip. I’ve been told that keeping the tank full will help to prevent condensation from collecting in the tank. Is this the best thing to do, or should I leave it partially empty until the next trip?

I also try to run the engine long enough to bring it up to operating temperature about twice a month when not otherwise in use.

How long will a tank of gas last before it is no longer usable?

B.G. Gotshall, F226696
Casselberry, Florida

A: I’ll start with your last question first. The length of time gas will remain usable is difficult to determine. The variables are almost endless. Where was it purchased? How old was the fuel to begin with? Is it a winter or summer blend? See what I mean? However, I can tell you that if your motorhome only sits for a month or two between trips, forget the fuel stabilizer. It’s wasted time, money, and effort. Today’s gasoline will last six months to a year without needing a stabilizer (with the above variables considered).

Moreover, you needn’t warm the engine periodically if you’re only parking it for a couple months. Just let it sit.

Continue to top off the fuel tank each time you park it. While this doesn’t eliminate condensation, it comes close to it. When the tank is full, there’s less room for moisture to collect, so the chance for condensation is greatly reduced.
“” J.B.

Q: I have a type A motorhome with a Chevy 454 Vortec engine. We travel all summer, but not during the winter, so the coach may sit for weeks or months in storage. I installed an engine battery shutoff switch to prevent any drain on the battery, but my mechanic tells me that I should not shut off the engine battery because of the computer losing stored information. Can you set me straight on this?

Don Wade, F143195
Sun City, Arizona

A: Your mechanic is right. Unless you’ve experienced a dead engine battery on your coach in the past, there’s no reason to use an engine battery shutoff switch. If you knew the computer’s wiring schematic well enough, you could keep the computer connected while shutting down the rest of the engine compartment, but there is no need to do this.
“” J.B.

Q: I own a GM bus conversion and need guidance as to the best methods for leveling the coach (using air bags or installing leveling jacks) while camping. I would appreciate it if you could point me to sources for information along this line.

John Knutti, F51156
Springfield, Missouri

FMCA’s “Business Service Directory” lists several FMCA commercial member companies that offer leveling systems for motorhomes. This directory appeared in the June 2002 issue and also is available online at www.fmca.com in the “Business Directory” section.

A: The July 2000 issue of FMC magazine included an article about leveling systems from seven different companies. The information might not be completely up-to-date, but the article might be a good starting place for gathering information. To obtain a photocopy of the article, please send a self-addressed, stamped, business-size envelope to the FMCA national office, attention Editorial Assistant.
“” J.B.

Q: I intend to tow a vehicle with my type C motorhome. It is all set to go, except I do not have independent braking for the towed vehicle. The vehicle is a 2001 Jeep, and it seems to be within the motorhome’s GCWR (gross combination weight rating). However, I heard that I might need independent braking for the Jeep. Is this something that various states watch, or an issue for which I could be stopped? Must I get an independent braking system, or is this something that is mentioned but not enforced? I have driven the motorhome with the towed vehicle locally and it doesn’t seem to be a problem, but I don’t want to get on the road and have a problem.

Jim Morse, F149908
Oakham, Massachusetts

A: The July 2001 issue of Family Motor Coaching magazine included an article by K. Stephen Busick about supplemental braking systems (page 60). The following excerpt from that article addresses your question about the need for such a braking system. A chart that outlines motorhome regulations by state and Canadian province appeared on pages 82 through 84 of the January 2002 issue of FMC magazine. It is also available online at www.fmca.com in the “For Members Only” section (member login required).

“Today, however, the need for supplemental braking is well known. It’s not unusual to find statements similar to this one from Ford Motor Company literature: ‘[The] towing vehicle’s braking system is rated for operation at GVWR “” NOT GCWR. Separate functional brake systems should be used for safe control of towed vehicles weighing more than 1,500 pounds when loaded.’ Other manufacturers have specified an even lower minimum weight at which a supplemental braking system is required.

“The question often asked is, Why aren’t larger brakes put on the chassis to compensate for a towed vehicle and/or related equipment? The laws of physics come into play here; the area inside the wheels of most coaches simply does not allow room for brakes that large. Chassis manufacturers and the makers of supplemental braking systems are filling a need coach owners have “” the need to operate our motorhomes safely and efficiently.

“Although it has been said before, it is nevertheless still true that while the braking laws of some jurisdictions may not apply to flat-towed vehicles, the laws of physics do apply. When the brakes on a motorhome are trying to stop a 3,000-pound load that is attached to the trailer hitch, they cannot tell the difference between 3,000 pounds of bricks and 3,000 pounds of steel. It is hoped that no one would haul the load of bricks without brakes on the trailer; it should be a given that the trailer is equipped with brakes.

“Some motorhomers maintain that until a uniform law requires supplemental brakes, they are not going to spend the extra money or time to purchase and use such a system. Currently, most states and Canadian provinces have braking requirements for trailers but many do not specifically address towed vehicles. The sheer terror that can exist for the few seconds when you don’t think you are going to be able to stop in time “” and the tragedy that can result “” can make a braking system a tremendous bargain.

“I have yet to hear any motorhome owner say that the brakes on his or her motorhome are too good and stop the motorhome too quickly. Until we have such motorhomes, anything that can make our trips a little safer is a good purchase, regardless of the price in dollars. Although not every jurisdiction requires auxiliary brakes now, the safety of loved ones and strangers is a good argument for using them.”

Q: Do you have any literature on changing the regulator and the polarity in a bus?

Fred Paschke, F306134
Wapato, Washington

A: Family Motor Coaching published a 13-part series titled “All About Buses” in the 1980s. One of the articles in the series (Part V: Electrical Ground Changeover) related specifically to polarity conversion (changing from positive to negative ground). A photocopy of the entire series is available by sending $2.50 to Family Motor Coaching, 8291 Clough Pike, Cincinnati, OH 45244; attention Editorial Assistant. If you are interested in only that one article, feel free to send a self-addressed, business-size envelope with a first-class stamp and we can mail it to you.

Q: We are the owners of a 1993 35-foot motorhome on a diesel-pusher chassis. In the design of the coach, it seems all of the heavy components were placed on the curb side. These include the television, the generator, three batteries, the propane tank, the water heater, the refrigerator, the wardrobe, most of the basement storage, and the spare tire. The street side of the motorhome has the basement air conditioner and a little room for storage.

Because of this arrangement, the coach leans heavily to the right. I had two new springs installed on that side of the motorhome, but six weeks later the coach leaned worse than it had with the original springs. It was suggested that I have helper air bags installed, but because of the square rear axle, I have been unable to locate any air-bag kits that fit. Is there a solution to my problem?

Bob Fisher, F234681
Gettysburg, Pennsylvania

A: The first thing you should do before trying to correct the situation is to weigh the coach. Look up “Public Scales” in your local Yellow Pages to find a weighing location. Then, weigh your coach with it packed for a trip and the tanks full. Obtain the total weight and the individual axle weights, and try to weigh each side separately, if possible. Then check these weights against the gross vehicle weight rating (GVWR) and gross axle weight rating (GAWR) listings on the manufacturer’s sticker near the motorhome’s entrance. In addition, read the maximum weight per tire on the tire’s sidewall and make sure you aren’t exceeding the allowable weight. If your weights exceed the motorhome’s limits, you’ll need to lower or redistribute the weight, and air bags will not help.
“” J.B.

Q: I currently own a 2000 Tiffin Allegro Bay 36IB on a Ford F-53 chassis. The gas-powered unit is loaded with options, and my wife and I like it, but we are considering upgrading to a similarly equipped diesel pusher in the future. The main reason for the change would be the added power and ride afforded by an air-ride suspension system. I have been doing some research on aftermarket equipment for my current coach, such as Fleetco Products’ rear air suspension, MOR/ryde International’s rubber suspension, and Banks’ PowerPack exhaust system. These products claim to improve performance but cost thousands of dollars to purchase and have installed.

My question: Are these products worth the cost or would my money be better spent on purchasing a diesel coach in a few years? I bought my coach new two years ago, and I am sure I’ll take a beating if I trade it in so soon. I have under 6,000 miles on it, and it is cleaner than the day I bought it!

Craig Guest, F274321
Reading, Pennsylvania

A: You ask some tough questions. Are you and your wife happy with your Allegro Bay? If so, why change? If you want more performance out of your coach, these upgrades can do wonders and are usually worth their cost depending upon how many miles you plan to put on the motorhome. Since you bought the motorhome, you’ve averaged less than 3,000 miles per year. All of this would enter into your decision as to whether the performance or ride enhancements would be cost-justified.

The same consideration would enter into a decision regarding buying a diesel. These vehicles are more expensive to purchase and to maintain than gas-powered motorhomes, so you’ll need to decide whether you’ll be traveling enough to merit the additional costs involved.
“” J.B.