'77 Brave refusing to keep battery charged

[snowbird]

*note to reader*  I am not an auto expert BY ANY MEANS.  You have my permission to talk to me like I am 5 years old

I have a '77 Winnebago Brave, Dodge 440 engine.  I've had this for about 6 months; prior owners let it sit for a year or so, but before that took her out across the country pretty much once a year for 30 years.  When I purchased it I drove it about 6 hours home without any problems.  Since then the following has happened:

I replaced both batteries.  3 times now I have had her out on the highway and at some point within about 30 miles from home she backfired and powered down while I was driving.  One of the batteries was totally dead.  The first diagnosis was a fuel issue; the mechanic replaced the fuel filter, started her up, and claimed she was fine.  The same thing happened again (also a dead battery).  The second diagnosis from the same mechanic was a belt for the alternator - they replaced the belt, started her up, and claimed she was fine.

A third time she powered down while driving, battery dead.  This third time I took her to a new mechanic.  They couldn't even start her without a new ignition coil and module (I am POSITIVE I am getting the part names wrong but hopefully you know what they are).  She is still at the mechanic while he further diagnoses her, but I'm hoping SOMEONE HAS A CLUE AS TO WHAT IS REALLY GOING WRONG???  I really want to travel with this girl, like, across the country, but I'm started to become fearful of driving too far and then getting stranded.  I"m also out of AAA tows


Thanks for any help!

[gadgetman]

Not enough info to really help you other than saying it is a charging system problem. Pattern failures would be the connector at the voltage regulator, the ground at the regulator to the rusted bracket it is bolted too, loose terminals at the alt. field connections.

Not sue why the wanted a coil and a module replaced with a dead battery. Coils seldome fail on these. Terminals do get rusty tho. The module failure does happen. Also there is a pickup in the dist which the magnets crack on and they wont trigger the module anymore and result in no spark while cranking. That pickup should put out a min of 500 mv on a good one. I can tell you from my usage that 125mv will still trigger the module but not well LOL. A new onw will put out 800mv or more cranking and 4v running.

[ClydesdaleKevin]

Yep, sounds like the alternator and or the voltage regulator.  Ask your mechanic to check the volts coming out of the alternator and the volts coming into the battery with the engine revved up to at least 2000 RPM.  You should be getting at least 14 volts.  If not, then its either a bad alternator, a bad voltage regulator, loose connections at the alternator or battery, or a loose connection somewhere along the way, like at a solenoid if yours is equipt with one.  Or the belt could still be loose if the last mechanic was an idiot.

Its the alternator that produces the current to charge your batteries, and the voltage regulator takes that voltage and converts it to DC voltage at the right amount, which again should be around 14+ volts when the engine is at higher RPMs.  Then the charge current goes through the wires to the batteries and charges them.  Its as simple as that.  Alternator makes the volts, regulator converts the volts, the wires carry the volts, and the batteries store the volts.  And then the engine and lights run off the volts stored in the battery.

Sometimes there is a solenoid in the path of the volts.  Its hooked up to the MOM momentary switch on your dash that allows you to start the RV from the coach batteries in a pinch, so have your mechanic check those connections for looseness as well.

Kev

[snowbird]

Thanks to the both of you - as I mentioned, I'm not that schooled in this type of thing, but will certainly pass off your suggestions to the mechanic, and will update you as to what happens!

[Oz]

And the mechanic should do the work for minimum wage if he doesn't already know how to troubleshoot a charging system effectively.  Maybe you should just give him the link to the charging system troubleshooting guides we have right here on CWVRV!

  One thing that ticks me off just about more than anything else... it's a mechanic who takes advantage of someone who doesn't really know about electro/mechanical stuff and just replaces things along the way until the problem is solved, wracking up a big, fat bill in the process.  Especially if it ends up being something really simple like a bad solenoid or a bad ground... which they usually wouldn't tell you either.  Okay, I'm done ranting....

[snowbird]

Thank you @Mark Sobyak!  I do know from my existence on other (non-RV related forums) the annoyance that is caused when people don't take the time to find answers within other posts on a forum before posting BUT - would you be so kind as to maybe show me where the troubleshooting guide for this type of problem is located?  I genuinely don't even know how to find this...

[Oz]

There are articles on batteries, testing, charging systems... and much more in the Member Area -> Free Manuals section.  This area is accessible to Full Members.

I would also suggest the following book as it is perfect for the novice RV mechanic (like me). 
http://www.classicwinnebagos.com/forum/index.php?action=store;sa=view;id=184

Everything I've ever learned about working on my Classic RV, I learned here, from other members and the resources I've compiled. 

(Any eManual purchase includes a one-year, free Full Member upgrade so, that gets you access to the free manuals & diagrams area and more.)

[LJ-TJ]

   
• Snowbird, I'm guessing that these mechanics are costing you a fortune. Now I know I'm opening a can of worms here when I suggest this and yes there are cheaper testers available but this one is idiot proof. Take a $100.00 bucks and go to Sears tool store and buy yourself one of these testers.
• http://www.ebay.com/sch/i.html?_trksid=p5197.m570.l1313&_nkw=Flut Testers&_sacat=0&_from=R40

It's idiot proof and the first time you use it you'll have saved the cost of the instrument. With this tester you can easily check the voltage output at your  alternator and follow the voltage back through to the battery. Just take the tester turn it on put one prob on the negative battery post and the red prob on the positive side and bingo if the battery isn't charging you can take this tester and start working your way back from the alternator to the problem. Really it's that simple with this tester. AND once you use it you'll wonder why you never bought one before. It's worth every penny you spend on it. And everybody here knows I'm how much of a neophyte I am when it comes to this electric stuff but it really works.

[vincewarde]

And the mechanic should do the work for minimum wage if he doesn't already know how to troubleshoot a charging system effectively.

Exactly.  All it takes to check the charging system is a voltmeter and a little bit of knowledge.  Once that's done, it can be more complex on older vehicles because you can have connector problems, but any mildly experienced HOME MECHANIC can do it, let alone someone who gets paid to work on cars!

[Froggy1936]

Hey Kev  its amps that are needed by the batts provided by the alternator and regulated by the regulator depending on the alternator they can be as high as 100 amps or down to 1 amp and the correct voltage is 14.2 V max  Frank

[ClydesdaleKevin]

LOL Frank...I was trying to keep it simple.  Just giving her simple terms and numbers to work with.


Kev

[DaveVA78Chieftain]

The best meter I have found for overall troubleshooting is Craftsman  Digital Clamp-On Ammeter (http://www.sears.com/craftsman-digital-clamp-on-ammeter/p-03482369000P).  Allows you to check both DC voltage and amperage as well as AC voltage and amperage.  Even has a temp gauge for checking Air conditioner in/out temperature drop.  Very few "clamp on" amp meters measure both AC and DC.  The vast majority are just AC clamp on meters. This one does both AC and DC up to 400 amps.

Goto my website (http://dave78chieftain.zxq.net/).  On left side under Charging System, select description and troubleshooting.  Dodge charging is simple and consists of the alternator, voltage regulator (external type) and the wiring.  Corroded wire connections can cause charging problems.  Alternator generates the voltage andconverts it to DC.  Voltage regulator senses the system voltage level and adjusts the output of the alternator.

Dave

[snowbird]

Hey Y'all.
New question:
How do I find this beautiful old Winnie a new home?
Sadly, we cannot afford to keep troubleshooting this battery problem and so it's time to find someone for her that can help.
K&S

[Oz]

Post your info on the Member RVs for Sale board, Craig's List, and any other free advertising site you can find.