Hi Dave,
I’m looking for a portable battery jump starter to keep in the motorhome. I occasionally have a dead chassis battery when I leave, rendering the Big Foot jack system also non-operational until we charge the battery. Motorhome has an 8.1L gas engine. Also, sometimes the battery is dead on the car, a 2018 Chevy Equinox. —Linda, 2005 Georgie Boy Landau
Hi Linda,
Since you indicated the RV has an 8.1L engine, it is most likely a Chevrolet Vortec on a Workhorse chassis. The Ford V10 that was available on the F53 chassis was a 6.8L engine, not an 8.1L. The Chevrolet Vortec was offered through 2010, after which new emissions certification requirements led Chevrolet to discontinue supplying engines to Workhorse. This coincided with a downturn in the RV market, particularly in the motorized segment.
Possible causes of dead battery
The recommended starting battery for this engine is 800 cold cranking amps (CCA). Since your RV is more than 10 years old, it’s reasonable to assume the original battery is no longer installed. If it is the original battery, it is likely weak and no longer holding sufficient charge to reliably start the engine. If the battery has been replaced, I would recommend confirming that it meets or exceeds the required CCA rating.
The next step would be determining what is draining the battery and how quickly it occurs. Some parasitic draw is normal from items such as the engine computer and radio presets, but the battery should not discharge completely within a short period.
In my experience, most units placed in storage will hold enough charge for six to eight weeks before reaching a low state. When possible, I use a trickle charger with access to 120-volt power or a portable solar panel designed to maintain the engine battery.
You can determine the amount of parasitic drain using a multimeter. Disconnect the negative cable, set the multimeter to the DC amp setting, and place the positive probe on the cable end and the black negative on the negative post. If there is a parasitic drain, it will flow through the multimeter and show the amount.
That said, I keep two portable jumper packs on hand and have used them successfully for several years.
One option for battery booster
One option is the NOCO GB40, a 1,000-amp 12V lithium battery booster. I originally purchased it for my truck and family vehicles, but I also used it to jump start a Class A motorhome on a Ford F53 chassis during RAGBRAI (Register’s Annual Great Bicycle Ride Across Iowa—the oldest, largest, and longest recreational bicycle touring event in the world) when it had a weak battery. It performed well in that situation; however, it is near the upper limit of its capability.
According to NOCO, the GB40 is rated for gasoline engines up to 6.0L and diesel engines up to 3.0L. The GB70 (2,000 amps) is rated for gasoline engines up to 8.0L but costs roughly twice as much. You can find one on Amazon here.
The jump starter I prefer
My preferred option is the ASTROAI S8 4,000A jump starter, which is rated for all gasoline engines and diesel engines up to 12L. I’ve owned one for more than two years, and it still holds a full charge despite only being used twice. I recommend recharging it at least once a year, or more often if it’s used frequently.
A representative from ASTROAI indicated it has enough reserve capacity to start a gasoline engine more than 20 times before needing a recharge. It can also fully recharge a cellphone multiple times, making it a useful option for boondocking as well. You can find this on Amazon here.
You might also enjoy these posts from Dave
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- Can different type and age RV batteries be mixed? Can I add a lithium battery?
- Will RV’s house batteries ‘play nice together’ if I replace chassis battery with lithium?
DAVE HAS ANSWERED MORE THAN 1,000 readers’ maintenance and repair questions. Read a directory here. There is so much to learn!
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
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