Jumpstarting a dead battery

chirorobacord · #1 10-31-2014, 09:56 AM

Can you safely jump start a RV through the cigarette lighter adapter? Is there any danger of damage?

DanH · #2 10-31-2014, 10:10 AM

No, too many amps.

erikpmort · #3 10-31-2014, 10:10 AM

uh nope.

what you need is a portable 12v jump pack that can go wherever your battery is. I tried long jumper cables from the car to plane before-- awkward and you need help!

airguy · #4 10-31-2014, 12:12 PM

Quote:

Originally Posted by chirorobacord

Can you safely jump start a RV through the cigarette lighter adapter? Is there any danger of damage?

Charge, yes. Jumpstart, no.

odens_14 · #5 10-31-2014, 01:34 PM

I have my 7 set up to charge through the 12 v plug. I have successfully "jumped" my weak battery with my charger when I left the master on while I was at a meeting. The battery was ok to run all my electronics but wouldn't pull the prop through a compression stroke. I believe my charger's hi setting is 10 amps, I plugged that in and was able to get the battery strong enough to start after about 15 min, and as fast as it spun the prop I'm sure it would have worked even earlier. Much more convenient than pulling the cowl or trying to pretzel through the oil door. The charger doesn't weigh much more than a pound and fits perfectly next to my fire extinguisher behind the passenger seat; Even though it's not the perfect solution I am glad I wired it this way.

however, if the battery is stone cold dead your definitely going to have to get directly to the battery or have a few hours to wait.

airguy · #6 11-03-2014, 09:01 AM

For those of us that park our airplanes with the flaps down to discourage people from stepping on them (which seems like a majority of owners, from my personal experience), here is an option. I installed a headset jack in the left fuse wall in line with the wing/flaps, such that it is exposed with the flaps down and covered when the flaps are up. This is wired direct to my battery with a 15-amp fuse and I have the plug end with wires/alligator clips on it to allow it to connect to any battery charger. If you choose to do this, DO NOT use a stereo headset jack, use a mono jack. The stereo plug will short the jack briefly as you install the plug into it, blowing your fuse on the first try. A mono plug/jack will work just fine.

The most likely time (by far) that you'll discover a dead battery is when you are returning to your parked airplane - and if you habitually drop your flaps when parking, then you've got a ready-made charging port. This port will NOT allow a jumpstart, but it will certainly let you charge enough to crank up in an hour or so.

BillFear · #7 11-03-2014, 09:23 AM

Quote:

Originally Posted by airguy

For those of us that park our airplanes with the flaps down to discourage people from stepping on them (which seems like a majority of owners, from my personal experience), here is an option. I installed a headset jack in the left fuse wall in line with the wing/flaps, such that it is exposed with the flaps down and covered when the flaps are up. This is wired direct to my battery with a 15-amp fuse and I have the plug end with wires/alligator clips on it to allow it to connect to any battery charger. If you choose to do this, DO NOT use a stereo headset jack, use a mono jack. The stereo plug will short the jack briefly as you install the plug into it, blowing your fuse on the first try. A mono plug/jack will work just fine.

The most likely time (by far) that you'll discover a dead battery is when you are returning to your parked airplane - and if you habitually drop your flaps when parking, then you've got a ready-made charging port. This port will NOT allow a jumpstart, but it will certainly let you charge enough to crank up in an hour or so.

We pretty much did the same thing as above but put our charging port inside the oil fill door. Wired direct to battery with fuse to allow a 10amp charge rate (but not a jump). I used the plug like the ones that come with a battery tender commonly used on motorcycles (positive side is well protected inside rubber plug).

AndyRV7 · #8 11-03-2014, 09:27 AM

Some interesting ideas. I too bought one of those battery chargers. It was about $14 at Wal-Mart, weighs next to nothing, and is pretty small as well. I think mine is 20 amps but it might be 10 amps. Plenty for a quick recharge if you run the battery down. My battery is on the top of my firewall, so I can reach it pretty easily through the oil door. It is also very handy for the times I am playing around with one of my displays in the hangar.

In a related note, I have a matching tire inflator. I was going to buy a compressor or the like for the hangar but got overwhelmed by the choices. It tops off my mains at 40 PSI in about 4 seconds (literally). Another great and inexpensive hangar tool!