Charging House Batteries
I have a 2006 Coachmen 38-foot diesel pusher on a Freightliner chassis with a 300-horsepower Cummins engine. I bought the motorhome new and found that the house batteries do not receive a charge while the diesel engine is running. I spoke with a Coachmen representative — the motorhome was still under warranty — and I was told that they did not run a charge wire to the house batteries because the alternator output was too high.
Do you concur with them? I have thought about putting a switched solenoid in line that I could turn on and off manually as needed from the driver’s seat. My other alternative is to fire up the diesel generator to charge the house batteries, but that is a waste of fuel. There are only two 6-volt-DC house batteries. The emergency solenoid does work in the event that I need to use the house batteries to help start the engine when the chassis batteries are low.
Duane Gordon, F379254
Carmel, Indiana
First, we must presume that your motorhome is equipped with a conventional 12-volt (to 14.5-volt) alternator and that the coach has a charging regulator. If so, there is no reason the house batteries can’t be charged from the alternator while the engine is running. This can be accomplished with a simple solenoid activated by the ignition switch to keep the coach batteries isolated from the chassis batteries when camping. A fuse sized at 135 amps should be installed in the charging circuit. Most diesel motorhomes are equipped with 135-amp or 160-amp alternators. Check the output of your alternator to match the fuse size to the alternator output and size the cables properly.
Battery Charging
I have a 2006 Damon Daybreak motorhome. It has two house batteries and one chassis battery. The unit has a nice stereo, with speakers in the bedroom and in the front living area. I assume that the stereo is powered by the house batteries, but I’m unsure. If we use the stereo while the engine is not running, and we are connected to shore power, will the stereo drain the chassis battery so that we would be unable to start the motorhome? I know that the house batteries should charge when connected to shore power, but does the chassis battery charge only when the engine is running, similar to an auto?
Terry Hastings, F418269
Swansea, Illinois
In most situations, the stereo operates off the house batteries, but it will not drain the batteries while you’re hooked up to shore power. Even if you’re dry camping, your lights inside the motorhome will drain the batteries more quickly than the stereo. Not knowing the specifics of your particular motorhome, I would say that in most cases when the motorhome is plugged into shore power, the house batteries are topped off first and then the chassis battery is charged. But you would need to check with Damon to determine exactly how your model is wired.
Clogged Tank
I have a 1998 Roadtrek 190-Versatile. The air vent for the fresh water tank had become stuck closed. I heard there were aftermarket vents but was having a hard time finding one for my motorhome.
So, I took it to a local shop, and they found that the vent had become clogged with dirt. The tank was removed and a new vent was installed. I wanted to pass this information on to other members in case they have a similar problem.
Mel Eberly, F247399
Myrtle Beach, South Carolina
Thanks for sharing this information, Mel.
AGM Compatibility
I have a 1999 Foretravel U270 diesel pusher. Is an AGM 8D battery compatible with the existing coach charger/converter? The coach currently has MK gel-cell batteries now.
Roy Lee White Jr., F117351
Deer Park, Texas
Both absorbed-glass-mat (AGM) and gel-cell batteries are lead-acid batteries and will work with your existing charger/converter. However, you should not mix them in your battery bank. Use all gel-cell or all AGM. I spoke with the folks at Lifeline, and they assured me that these batteries are compatible. However, you might want to call the company (800-527-3224, 626-969-6886) and speak to Jim, Dave, or Justin so there won’t be any misunderstanding.
One other thing you need to check is that the charger/converter is reprogrammed/dip switches reset for AGM batteries. If there is no AGM setting on the unit, put it to the wet-cell setting, as the wet-cell charge program is very similar to that for an AGM battery but different than that for a gel-cell battery.
Tire Filling
After having trouble getting air into the inside rear tires of my Itasca Sunova for years, I finally gave up and took the motorhome to a shop. Then I saw a truck stop specialist spend more than 30 minutes attempting to put air into the rear tires. So I came up with a solution by taking off the decorative hubcaps whenever I check or fill the tires. That gives me full access to the valve stems for both the inside and outside tires without worrying about extensions and any of the problems associated with their use. If you desire that the hubcaps stay on, just be prepared to spend those few extra minutes to remove and reinstall them when you check the air pressure.
Ron Secord, F325488
Sun City, Ariziona
Thank you for your suggestions, Ron. However, I’d personally suggest installing metal valve extensions for the inside rear dual tires. I’ve had them on my motorhome for almost a decade now without any problems — and I can leave my hubcaps in place while driving and when checking tire pressures.
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