Maintaining Batteries

smhaack63 · January 09, 2017, 09:43:39 PM

Please Help! Apparently, I've gone totally crazy and bought a bus for my wife and I to live in. It's a 1980 MC9 with two 12V batteries wired in series, making 24V. I want to connect a battery charger/maintainer to prolong their life. Can I use a 12v charger or Do I need a 24V charger?, Can I disconnect the link between the two batteries and charge/maintain them separately with a 12 volt charger?

gumpy · January 09, 2017, 09:52:40 PM

Yes, you can charge them separately with a 12v charger. You don't need to disconnect the cross cable. Just connect your charger to each battery individually.

If you want to charge them both at the same time, them you would need to disconnect the cross cable, and connect them in parallel with jumper cables. Of course you should
have the master switch off and probably should disconnect the ground to frame, also. The downside is you'll have to reconnect everything whenever you want to use the bus. Not difficult,
but tedious.

If you just disconnect them at the battery switch and remove the ground to frame, they will likely maintain a charge for several months. I say remove the frame ground because they are notorious
for having phantom 12v loads which will drain the batteries even when the disconnect is thrown.

luvrbus · January 10, 2017, 07:38:44 AM

I just use a 24V regulated scooter charger on my MCI a good one cost around 20 bucks pay no attention to plug end cut it off and it only has a + and - wires add the clips and you have a 24V charger, it keeps my 8-D's ready to go

PP · January 10, 2017, 08:47:42 AM

I have 2 - 12V battery maintainers on my coach bats that are wired to deliver 24V at the batteries. They cost about $20. each and I plug them into an outlet in the battery compartment only when I sit for a while. DO REMEMBER TO PULL THE MAIN DISCONNECT or your batteries will drain while sitting. I haven't had any problems leaving the bats connected from phantom drains so long as I PULL THE MAIN DISCONNECT switch.

I forgot to add--nice looking bus. (drool) Keep us posted on the conversion.

luvrbus · January 10, 2017, 09:16:30 AM

If you have a DDEC engine it is best to leave the batteries hooked up and maintain them with charger, over time the internal battery will go bad from the drain and it sucks paying $200.00 for a $5.00 backup battery in a ECM

rusty · January 10, 2017, 10:46:54 AM

Where pray tell can you get a backup battery for the ECM for 200. I looked into it for my DDEC V and it was 1500.

Wayne

luvrbus · January 10, 2017, 11:04:07 AM

Quote from: rusty on January 10, 2017, 10:46:54 AM
Where pray tell can you get a backup battery for the ECM for 200. I looked into it for my DDEC V and it was 1500.

Wayne

Wayne, DCS (Diesel Control Services) in Cheswick Pa but he charges $500.00 for the V DDEC add another $100.00 for shipping both directions

AdamWalkup · January 10, 2017, 01:20:13 PM

Have you worked with "DCS" in the past, and what was your thoughts of them? With 18 series 60's, I'm always having ECM problems, and have had a hard time finding a GOOD aftermarket person. Now that Detroit is up to over $2,000, and I have had some of their units fail in less then 2 years, I'd sure like to find a good reliable aftermarket ECM guy.

Any thoughts??

daddysgirl · January 10, 2017, 02:30:02 PM

In addition to the points already made, if you have the 12-volt line to front stud 55 connected to anything, it will drain the left bank if you don't keep a trickle charger on it.
I have a charger that uses red and green lights to indicate charge on each bank... easy peasy

smhaack63 · January 21, 2017, 09:35:27 AM

Wow! Thanks all for the helpful advice. I definitely have a lot of learning to do.

I understand that some of the posts in this thread do not pertain to me, but I am still interested in learning. What is an ECM? Is an ECM an Electronically Commutated Motor? I know what an Electronically Commutated Motor is but I don't know how that fits in this conversation.

Also, I don't know what DDEC is. If anyone has links handy to informative websites and can post them here it would be greatly appreciated.

Oonrahnjay · January 21, 2017, 09:51:53 AM

Quote from: smhaack63 on January 21, 2017, 09:35:27 AM... What is an ECM? ...

"Engine Control Module" - the computer that operates the fuel injection, senses the different operating inputs (temperature, sometimes crankshaft position, etc.) in the engine, etc. Details vary on different types of engines but that's the basics of it.

On "DDEC", somebody with a Detroit will have to tell you.

Lee Bradley · January 21, 2017, 10:03:44 AM

Detroit Diesel Electronic Control (DDEC) system