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Alternator quit on road

August 22, 2012, 04:25:47 pm

I left home this morning, and all systems seemed to be working.  My voltage was reading about 13.  A few miles down the road the voltage started dropping.  I pressed the boost switch with the house generator running, and the voltage started going back up to a little over 12.  I went ahead and drove to my destination about 200 miles away.  I plan to be gone from home for about 10 days and plan to drive another 400 miles or so on 2 different days.  My question, is it OK to continue to run this 400 miles using the boost switch and the house generator to keep the engine batteries charged for the trip, and deal with the alternator when I get back home?

When I arrived at my destination, I looked in the engine compartment to make sure the generator belt wasn't off or broke.  It was fine.

Jim Broadhurst

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Re: Alternator quit on road

Reply #1 – August 22, 2012, 04:50:56 pm

Jim,

Yes, you can use the boost switch to enable the inverter/charger to charge the house battery and then through the boost switch to charge the chassis battery as well.

Do that while on shore power to get the chassis battery up to full charge before you start.  Leave the boost switch on while you start the engine to minimize amp draw on the chassis battery and keep all 12 VDC consumption to a minimum (i.e don't drive at night if you can help it.

Were it me, I would do a quick check with a voltmeter at the large lug of the alternator as well as at both battery lugs of the battery isolator to see if you can find the problem. Sure, it may be the alternator, but it could be something else-- even something easy to fix.

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Re: Alternator quit on road

Reply #2 – August 22, 2012, 06:00:37 pm

Thanks for your input.  I will check it as soon as I get a voltmeter.

Jim

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Re: Alternator quit on road

Reply #3 – August 22, 2012, 06:16:24 pm

Any Sears, Radio Shack, etc-- start under $20.  A "must have" tool.

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Re: Alternator quit on road

Reply #4 – August 22, 2012, 06:45:04 pm

That will work just fine. Also, keep the boost switch on while you are parked and plugged in to keep the chassis battery up.

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Re: Alternator quit on road

Reply #5 – August 23, 2012, 01:04:10 am

We have driven for over a week without a working alternator by running generator with boost switch on. We did not want to disrupt our travel up the east coast to fix the alternator and waited until we arrived in a large city.

But meanwhile you can do some diagnostics on why you are not charging batteries with alternator.

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