Hooking up Battery maintainer on sprinter

[coloradohi1]

Hi again. Winnebago 24j on a sprinter, diesel engine. It has a 12v plastic
covered metal stub mounted on the engine. It is red and marked 12v.
When the cover is pushed back and the voltage measured, it reads the
battery voltage. I am planning on hooking a maintainer to that this
winter to keep the battery from discharging. Should be ok, but wondering
if anybody has any negative thoughts?

Dave

[Winterbagoal]

The 12V DC outlet below the pull out ash trays in some/many of the Sprinters are always "live" and attached to the chassis battery, if that might be an easier option for you?

[coloradohi1]

Thanks for the reply. Yes have been thinking about doing that. Just have to hook my
maintainer to a plug that would fit.
Thanks

[Winterbagoal]

I bought a pair of Stanley Fat Max 8amp charger/maintainers at Walmart a few years ago, when I replaced my first set of batteries in the Roadtrek - it/they came with alligator clamps, eyelets, and a cigar lighter connector for the output.

In the Navion, I just plug it into the 120VAC inverted outlet on our outside bathroom wall, and plug the cigar lighter into that ashtray 12VDC outlet, fire it up and it's done.

[Lmonger]

I have 2017 Sprinter 3500 on 2018 View 24J(4 agm’s 326ah) charge chassis using - when Shore power or solaring - Harbor Freight 4amp HF charger on AGM in lower level lighter outlet it’s live 24x7 so far so good.

[Jim Schmidt]

Yes you use the red plastic covered post to charge the Sprinter’s battery. I might suggest you simply disconnect the Sprinter’s battery when it is not being used. The disconnect is located right above the accelerator peddle on my ‘08 model. Never need to charge the disconnected battery after 6 months of storage.

[Shedboy]

No negative thoughts, might work. I have 2012 Navion 24M bought HF's single solar panel put it on the dashboard and plugged it into the lower cigarette lighter socket, worked fine in sunny Colorado!


I then purchased HF 4 amp battery maintainer and permanently connected it to the "hot" lug (not used for anything else) under the drivers seat, (velcroed the charger to the inside vertical seat pedestal) and ran a 110VAC extension cord through the big hole under the seat to the aux TV power socket in the side compartment, tie wrapping the cord under the chassis.
It works and now the chassis battery is charged any time shore power is hooked up or the generator is run or the inverter is used, an improvement over original.


One area of concern is that I'm not sure how much voltage the HF Maintainer will tolerate being applied to its output wires from the alternator if the engine is running and shore power connected at the same time. So far, no smoke, but I have purchased a blocking diode that I will install just in case!


Another unknown is what happens to the HF Maintainer when/if the inverter supplies non-sinusoidal voltage to it? Charting the unknown............

[Trooper]

I have a trickle charge set up between the coach batteries and the start battery. When the shore power is on the trickle charger will keep the start battery charged even during the winter.I have forgotten the name of the trickle charger but it works well. This was on the coach when I bought it used.

[Camper Ken 2]

Originally Posted by coloradohi1

Thanks for the reply. Yes have been thinking about doing that. Just have to hook my
maintainer to a plug that would fit.
Thanks

It should go without saying, but I'll say it anyway ... be sure you have the polarity correct.
Here's what I use.
Battery Tender Plus High Efficiency 12V 1.25 Amp Battery Charger
I installed a 12 volt power plug on it and plug it into the outlet below the cupholder which is live all the time, and feeds the Battery Tender to the chassic battery.
I got mine at Walmart for much less than the price on the internet.

[jcurtisis]

Dave, I have successfully been using a Mercedes-Benz trickle charger: A0009822921 for about 2 years; attached to the battery charging posts in the hood compartment (as you noted above). I drop the power cord down under the engine (plenty of room to do so) and plug it into attach an extension cord. I do this whenever I park for a long time. It is true you can charge up the battery and then disconnect as part of a “winter lay-up”. I have found the trickle charger my best option as the battery would slowly loose charge when hooked up, so I use it all the time when on the road or at home. ~$160 on Amazon; just search using the model number...many lower cost options popped up on eBay...

[coloradohi1]

Thanks for the reply,

I decided to trickle charge it thru the internal plug. I had a maintainer,
so modified it with a plug. The plug was rated up to 5 amps. Since I have
the RV plugged in any way, I can just plug the maintainer into one of
the RV's 110 sockets.. It is only drawing a little over 3 amps until the
battery is fully charged.

Thanks for all the info,

Dave and Cindy Beach