Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Discussions => Topic started by: Tim on September 15, 2016, 09:22:58 am

Title: Keeping chassis battery charged for trip home
Post by: Tim on September 15, 2016, 09:22:58 am
Bought the aforementioned 1997 U270 for $28,000. Here is my analysis:

N E E D S
- Charging voltage at coach battery, which runs the engine, reads low.
  I will buy a digital voltmeter today and investigate whether it has a bad alternator.



Has anyone ever ran a jumper from the house batteries to the chassis battery? Would it do any harm? I did this in my Fleetwood Southwind and worked fine.



[split this out from the original topic - Michelle]
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: George and Steph on September 15, 2016, 09:29:22 am
Won't boost switch give you the umph?
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: John44 on September 15, 2016, 09:30:02 am
That is exactly what the boost rocker switch does.
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: Caflashbob on September 15, 2016, 09:37:14 am
Boost switch consumes 3amp.  magnetic switch zero.

But to get it home the boost switch is safer
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: wolfe10 on September 15, 2016, 09:57:01 am
Tim,

Congratulations.

If the coach has been sitting, and did not have an owner-added charging system (several different kinds) for the chassis batteries, they could have just run down and just need a charge.

Yes, to check the alternator is pretty easy with a digital voltmeter (even a cheap $10 one):

Engine running at high idle-- around 1000 RPM (use cruise control to bump up idle speed if no helper along).

Check voltage at both chassis and house battery banks.  Should be 13.5- 14.2.

If not, locate the battery isolator (about 4X10 inch finned box with battery cable size wires to it).  Check voltage at the center lug which comes from the alternator B+ terminal.  Should be 14.0- 14.7 VDC.

Let us know what you find.
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: krush on September 23, 2016, 10:22:26 pm
Has anyone ever ran a jumper from the house batteries to the chassis battery? Would it do any harm? I did this in my Fleetwood Southwind and worked fine.

I removed the combiner and installed this. It works both ways (chargers house batteries from alternator OR charges engine batteries from battery charger)
Title: Re: Keeping chassis battery charged for trip home (split from Re: WANTED: Foretravel...)
Post by: wolfe10 on September 23, 2016, 10:46:12 pm
Tim,

No problem using a jumper, assuming you do it properly.  Do NOT use alligator clips or battery cables that could jump off a lug and have a very high amp dead short to ground were either end to touch any coach metal.

And, as you are aware, this would allow all batteries to discharge together as well as charge. Could leave you with no batteries to start the coach or generator.