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Topic: Alternator and battery recommendations for 2006 LD? (Read 282 times) previous topic - next topic
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Alternator and battery recommendations for 2006 LD?
My RV would not start and would not take a trickle charge (it stayed at 0 on the charger). I called AAA and the battery technician jump started it but it immediately died once he took off the jumper cables. He said my alternator needs to be replaced first, and that the battery probably has a dead cell(s).

Looks like there are many choices of alternators at AutoZone and other sites. Any advice on which alternator would be best for my 26.5 foot E450 LD?

Also, Costco sells an Interstate battery that fits. Is that a good brand?

Thanks in advance.
2006 RB
Re: Alternator and battery recommendations for 2006 LD?
Reply #1 –
Hi Cebuano;  The AAA people see a lot of dead batteries, and it sounds like you could use a new one. Costco Interstate batteries are good, I use those both as engine batteries, and the deep cycle golf cart ones as house batteries. If the engine start battery is over five or six years old it is time.  As far as the alternator, I would hold off on that. The AAA people aren't mechanics and the circuitry in a motorhome is a lot more involved than that. I suspect that a new battery will solve your problem.
      When you start the engine up, check that the voltage on your battery goes up to about 13.8 volts or up as high as 14.8 volts. If it does, then your alternator is ok. There have been a lot of rats running around our area lately, chewing on wires. An inspection of your engine compartment might reveal some issues.   Let us know your results.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Alternator and battery recommendations for 2006 LD?
Reply #3 –
Quote from: Cebuano54  - 
He said my alternator needs to be replaced first, and that the battery probably has a dead cell(s).
The output of the alternator goes through a battery isolator, which charges both chassis and coach batteries. If the chassis battery had a shorted cell, the drain on the charging circuit may have killed a diode in the isolator. This can be easily checked.

Steve
2004 FL
2013 Honda Fit
Re: Alternator and battery recommendations for 2006 LD?
Reply #4 –
I am totally ignorant about this, but if the jump by AAA started the RV engine but  then it promptly died when the jumper was disconnected suggest that something g other than the battery is bad?
2006 RB
Re: Alternator and battery recommendations for 2006 LD?
Reply #5 –
I agree with Ron's suggestion not the change the alternator until the battery has been replaced.
The alternator needs a power source to activate, if the battery is dead, it needs to charge a while, at a high idle, to charge the battery to a high enough voltage to energize the alternator and to satisfy the engine's other electrical needs.
With a dead battery, at idle the alternator does not produce enough voltage to operate the computer, ignition, fuel injectors and fuel pump. The battery is needed at idle to stabilize the voltage, keeping a high enough voltage to operate things.
BTW, idling at the engine's normal speed produce very little battery charging. If the engine is used to charge coach battery, maintaining a speed of 1500-2000 RPM is recommended, for a minimal charging time.

Try jumping the battery and once the engine starts, keep it at 2000-RPM for ten minutes. Unless the battery is internally shorted, it should keep running . If the engine speed drops too low, it will stall due the alternator not producing enough voltage at idle.
Your rig could also have wiring or connection issues, long distance troubleshooting is hit and miss, any times things that are obvious, in person, can be difficult to solve remotely.

If the alternator is bad, I would stay away from the discount auto parts stores, with either Napa or a brand name rebuild from Rock Auto.
Inexpensive rebuilt alternators are usually junk, cheaply repaired with just the broken or defective part replaced .
A full rebuild will include bearings, brushes, diodes and slip rings, among other parts.
A lifetime warranty on a cheap rebuilt is the last thing I'm looking for.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Alternator and battery recommendations for 2006 LD?
Reply #6 –
Actually Cebuano, Having the engine die when the jump start battery source is disconnected pretty much points to your battery as the culprit.  If you take the battery out, can you charge it and have 12.6 volts without the charger attached? If you can then there could be something else wrong. My experience has been that the rest of your system is pretty hardy, and it is most likely just the battery. Start with that, before you start digging around in the rest of the 'guts'. That battery technician... a few might actually know what they are talking about..... Motor homes are much more involved than most cars. (until you start talking hybrid, or auto start/stop, electric assist etc.)  As Steve mentioned other things could be bad (diode in the isolator). The alternator would be near the bottom of the list of where to start. Fusible links, wiring defects, connection integrity, etc.
  Just how old is this engine battery? and if I may ask how many miles on the motor home ('06 RB was it ?)    RonB   
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Alternator and battery recommendations for 2006 LD?
Reply #7 –
Bought a battery and will install it tomorrow. It only has 38k miles and I am embarrassed to say only about 2k since I bought used two years ago. Retirement got pushed off a year or two. Don’t know how old the battery is but guessing 3-5 years (have to look at the records).
2006 RB
Re: Alternator and battery recommendations for 2006 LD?
Reply #8 –
Cebuano; With that low miles since you've owned it, be advised that there isn't anything charging your engine/chassis battery. In your year the solar only charges the house batteries. The engine computer idle parasitic power drain, and plain old lead acid self discharge will kill your battery, even a new battery. A Trik-L-Start auxiliary charger can keep the chassis battery charged if you have active solar panels. Just a few minutes of engine idle, as Larry said, won't be enough to keep the battery up. A plug in trickle charger https://www.harborfreight.com/automatic-battery-float-charger-42292.html    (Harbor Freight) can keep the chassis battery charged up.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Alternator and battery recommendations for 2006 LD?
Reply #9 –
I changed the chassis battery and it worked. Runs and idles fine now. Thanks for all the advice! Just saved a couple of hundred dollars.
2006 RB
Re: Alternator and battery recommendations for 2006 LD?
Reply #10 –
Quote from: Cebuano54  - 
I changed the chassis battery and it worked. Runs and idles fine now. Thanks for all the advice! Just saved a couple of hundred dollars.
Check the voltage on battery while running. Should be > 13.6V or it won't keep running long...

Steve
2004 FL
2013 Honda Fit