Battery Question

[Randy Perry]

So this past weekend I was dry camping (arrived Thursday night and left Sunday morning. I ran my gen set for 3 or 4 hours on Friday & Saturday, ran my inverter in the evenings. When I went to start my coach Sunday morning, I didn't have enough juice to start her? Since my coach batteries were showing 13+ volts, I hit my battery tie switch (and could hear the solenoid engage) but had no effect on the starter. I then hooked my (tow) Jeep to my chassis batteries with jumper cables and couldn't get it to fire! I then hooked up a 2/10 amp battery charger in addition to the Jeep and after 3 or 4 trys, got it started. Now for my question, are my (2) chassis batteries wired in seires and the Cat motor requires 24 volts??? Aside from typical battery maintenence, I never paid attention to how they were wired! This thought came to me on my way home thinking that was why I was having a hard time starting a 24 volt system with 12 volts!! Is there any charging system for those batteries while you're on shore/generator power?

[LEAH DRAPER]

"Is there any charging system for those batteries while you're on shore/generator power?"


There was no method for charging my chassis batteries so I bought a Battery Tender at Camping World and plugged in the a/c outlet in one of the bays.  Then so I didn't have to disconnect it from the batteries each time I moved, I had the wires run from the battery compartment to the Battery Tender via the frame.  Now when ever I am plugged into shore power my chassis batteries stay charged.  

[Gerald Farris]

The chassis batteries on your coach are wired in parallel, so they are operating as a very large 12V battery. The reason that it is hard to start the coach with jumper cables is that the amperage required to operate the starter is much higher than a set of light duty cables can provide.

Your coach has an Echo Charger to maintain the charge state on the chassis batteries. If the house batteries are being charged the Echo Charger will furnish up to 15 amps to the chassis batteries to maintain their state of charge if it is operating properly.

The probable cause of your problem is probably a bad chassis battery. I would have a load test run on both chassis batteries individually and replace the bad battery, or both batteries if one of the batteries does not pass the test with flying colors.  

Apparently you also have a problem with the boost (battery tie) solenoid, because if it was working properly the coach would have started when it was held engaged at the same time the starter was engaged.

Gerald

[Bruce Benson]

Just for clarity here, the bat tie switch is a hold down switch.  The switch must be held down to maintain the tie between the systems as you crank the starter.

I agree with Gerald that the battery is suspect due to the short amount of time you were parked, unless there was some drain on the chassis battery that you did not disclose.  They should be good for more than 4 nights under parasitic chassis loads.  

The Echo Charger is not my favorite item, made by Xantrex, not my favorite company.  I have had two fail and the previous owner had at least one fail.  I would check it to make sure that it is working.  Check the fuses on it as well as the connections, particularly the ground.  Mine was located on the left upper wall of the battery bay.  

I prefer the Ultra Trick-L-Start over the Echo Charger, it does about the same job, costs less, is sealed from acid fumes and lasts longer, at least for me.  

[Randy Perry]

Thanks everyone! I think I'll start with (2) new chassis batteries and get a battery tender!

[Gerald Farris]

Randy,
Don't just go and buy new batteries without testing your old batteries first. You can take your old batteries to any large volume battery dealer and they will test your old batteries at no charge in the hope that they can sell you new ones if yours are bad.

Next, check your Echo Charger by checking the voltage at your chassis batteries when on shore power with the batteries being charged. If the voltage is above is 12.8V to 13V, your Echo Charger is working properly and buying a battery tender will be a waste of money.

Gerald

[Richard And Babs Ames]

Our 1997 Patriot did not have any type of echo charger or otherwise to keep the chassis batteries charged. We found out the hard way after Hurricane Charlie and 7 days of boon docking in the driveway. We installed an echo charger. Monaco/Beaver said that it was a bad design decision by then SMC/Beaver.

[Gil_Johnson]

I'm a bit surprised that Beaver didn't engineer a way to charge the chassis battery, especially given they provided a means to parallel the two battery banks.  This is something they corrected in newer coaches.  The solution they installed in my 2008 Contessa seems much more bulky than I would have expected and what I've seen on boats.  Rather than installing an echo charger I'd install a smart battery combiner/isolator.  Although you can find others for much less money (this one is about $140), here's a great example of an ideal battery combiner/isolator that supports extreme current with both a remote and manual battery combiner capability. http://bluesea.com/category/2/products/7622 This has the added benefit of charging both banks from the engine's alternator when you're driving.  I assume you don't have this capability either.

BTW, I'm with Gerald, don't replace what hasn't been determined to be bad, as you may not fix the problem.

Gil

[Gerald Farris]

The Patriot and Monterey coaches from the mid nineties had battery isolators, so they did charge the chassis and house batteries from the engine alternator. The method that was designed into them to charge the chassis batteries when on shore power was a continuous duty boost or intertie solenoid that had a feed wire to activate it from the accessory side of the ignition switch. So to keep your chassis batteries charged when on shore power or generator, you would have to turn the ignition switch to accessory for an hour or so occasionally to keep the chassis batteries charged.

Since this system was not automatic and required owner action, it was not a success at solving the discharge of the chassis batteries. Therefore Beaver started installing automatic systems like Echo Chargers to maintain the batteries.

Gerald

[Randy Perry]

OK, battery check will happen before replacing! So, what could have put a draw on the chassis batteries while I was dry camping??? I've gone a month or two without using the coach (although plugged into shore power) and fired it up without a problem? What runs off the chassis batteries besides engine start, running/head lights, maybe the hydro jacks......I'm at a loss!!! (BTW, she fired up fine this afternoon to move it???)  

[Gerald Farris]

If nothing was left on, the only thing that will run down the chassis batteries is the normal parasitic drain from the engine computer. All computer controlled engines have this drain, and that is what makes the use of a charge maintainer like an Echo Charger necessary.

In your case it is probably the failure of a chassis battery that caused the problem, and a failure of the boost solenoid system that prevented you from starting the coach with the help of the house batteries.

Gerald

[Randy Perry]

Well, heading to Vegas this weekend and don't expect to have a problem but who knows :-/ Will have to work on fingering out this problem next week Thanks Gerald for all your input

[Richard And Babs Ames]

Gerald, I checked the blue chassis owners manual and I did not find a reference to to turning the ignition switch to acc to charge the chassis batteries.

It must have been discovered by an owner and spread by word of mouth at rallies. It seems more of an accident than a design in feature. It is good information though but not a good solution to keeping the chassis batteries charged IMO.

[Edward Buker]

A couple of things that might help if you have trouble starting due to depleted starting batteres, or a bad emergency start solenoid.

As Gerald indicated, you must hold down the momentary switch that causes the battery bank solenoid to tie the two battery banks together. It should be held on for several minutes before trying to start the engine in order to allow current to bring the starting batteries up a bit from a dead state. This will ultimately provide more starting current to reach the starter.

If under those stressful conditions you learn that the batteries as well as battery jumper solenoid has failed, which is a very common problem, this should help. I have had great success using both the positive and negative cables in parallel. You would tie a jumper cable to each positive post of a starting battery (they are in parallel @ 12V) and then the other ends to the 12V positive posts of the house bank. (series/parallel combination for 6V batteries. Be sure to be on the 12V side where the bank main red lead to the house wiring is tied in) Because both battery banks are already wired together to the main chassis ground lug you do not need to jumper the ground side. If starting batteries are depleted wait several minutes with the cables connected before trying to start.

If you would like to do a very inexpensive upgrade to your battery wiring you can buy a short heavy premade black battery cable (I used NAPA) with suitable lugs on the end. I tied the starting battery ground to the house battery ground at the battery terminals. This lowers the wiring resistance of the starting circuit and allows a second ground path from the starting batteries to the chassis frame.....more strands is better for high current demands like a big starter.

I have an Echo charger and probably by luck it is mounted quite high up on the left side in the battery compartment near the front of the compartment. I have seen no signs of corrosion and have not had any fails. While stopped, the main outgassing of acid fumes from charging would be coming from the house bank and tending to travel downward. If your Echo charger has been failing check and see if it is mounted in the best location for survival. It does not have to be in the battery compartment as long as the cabling gauge is of a sufficient size for extending the leads.

In the battery department...When I bought our coach it had a pair of one year old "off brand" Group 31 batteries. They failed on the road a month after we bought the coach. I pulled those batteries and replaced them with NAPA commercial Group 31 batteries which were substantially heavier which have been fine. I'm not trying to endorse any brand just letting folks know that some brands of battery quality leaves a lot to be desired, particularly in our heavy duty application.

Hope this helps....Later Ed

[Bill Sprague]

I helped put one on my son's motorhome and it has worked well.  Winnebago (who is still in business!) uses them on their diesels.  

"The Trik-L-Start device monitors battery voltage in the house batteries and compares it to the chassis battery. When the Trik-L-Start senses the chassis battery voltage is approximately ½ volt lower than the house battery, it allows up to 5 amps current flow to the chassis battery. The circuitry within the Trik-L-Start prevents back feeding of electricity from the chassis to coach battery so if 110V power is interrupted, the chassis battery will not be discharged."  

In other words, when plugged in to shore power, the Trik-L-Start borrows from the house batteries to charge the engine batteries.  There are only three wires.  Black to ground, blue to the engine battery and yellow to the house battery.  The unit is about the size of a deck of cards and can go anywhere in the battery compartment.

If my Beaver supplied "Big Boy" and BIRD relays fail, I will probably replace them with one of these because of the simplicity and lack of moving parts.

You can buy one here:  http://www.lslproducts.com/TLSPage.html