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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: siberyd on April 26, 2013, 07:42:25 AM

Title: 4104 Owner Battery Question
Post by: siberyd on April 26, 2013, 07:42:25 AM
Greetings All,

I am having some start battery problems and got to wondering a few things:

1. What size start battery or batteries on your coach.
Mine are 2 - 4D batteries with 1000 CC amps.

2. What size house battery or batteries?
Mine is 1 - 8D battery with 1200 CC amps.

I seem to have a battery drain when all switches are off. My saturday project is to track it down.

Thanks in advance.

Siberyd
Title: Re: 4104 Owner Battery Question
Post by: Lin on April 26, 2013, 08:01:23 AM
2 4D batteries should be more than enough for your start batteries.  There are many the use 2 groups 31's.  You could try turning off your battery disconnect if you have one to see if they still drain, or put an ammeter to them to see if there is a draw while things are turned off.

The size of the house bank would depend on what you are using it for.  Is the 8D you are using for that deep cycle?
Title: Re: 4104 Owner Battery Question
Post by: siberyd on April 26, 2013, 08:38:32 AM
House battery is not a deep cycle, just a standard 8D battery. My PO had it set up that way so I have not changed it out yet. It will be a future purchase when we start using it more than twice a year.

Siberyd
Title: Re: 4104 Owner Battery Question
Post by: gus on April 26, 2013, 10:57:53 PM
Lin is correct, I have two Gp 31s starts, which are smaller than the 4Ds, and they are more than enough in moderate climates.

I have separate, inexpensive "green knob" cutoffs on all my batteries, makes slow drain problems or electrical work much easier to handle.

Baggage compartment lights are a good place to start looking for leaks.
Title: Re: 4104 Owner Battery Question
Post by: zubzub on April 27, 2013, 05:53:35 AM
One group 31 will start my 6-71 even in the fall.  As far as the power drain is concerned that will take some time, any one of the many ancient relays could be stuck along with dozens of other possible shorts etc... I would start by checking out the main On switch and associated relays.  Hardest thing to trouble shoot on my 4104 is 'lectrics.
Title: Re: 4104 Owner Battery Question
Post by: TomC on April 27, 2013, 07:35:12 AM
I have 2-31's to start (8V-71) and 2-8D's for house. The AGM 8D's are rated for deep cycle and starting. I have a jumper solenoid that connects the deep cycle to the starting batteries mainly to charge the deep cycles going down the road (since my refer is electric). I have started the bus on the deep cycles when the starting batteries have failed-also helps when the weather is cold. Nice to have the redundancy. Good Luck, TomC
Title: Re: 4104 Owner Battery Question
Post by: gus on April 27, 2013, 01:15:02 PM
I have the same setup as Tom, can't really imagine any reason not to have this kind of hookup.

It has saved my bacon more than once.

The main reason I have two starts is for backup, I've had one start fail a couple of times and the remaining one saved me. It also helps in cold weather but I don't often travel in cold weather.

However, when one shorts out it usually kills the other one also. Had this happen too!

When ,y 4Ds fail I'm going to Gp29 or tractor batts since they are easier to find around here than Gp31.
Title: Re: 4104 Owner Battery Question
Post by: siberyd on April 27, 2013, 03:20:05 PM
Still working on tracking down my short. In the process I have found a solenoid mounted to the bulkhead and a jumper clip. Following the wire it goes to the start batteries.

Now to track down the short.

The group 31 batteries cost the same as 4d. I work in a town that is one of the major trucking areas in southern Calif.

Siberyd
Title: Re: 4104 Owner Battery Question
Post by: Mex-Busnut on April 27, 2013, 04:06:26 PM
I claim to know absolutely nothing about 4104's, other than that they were made by GM and are awesome-looking old buses.

Let me emphasize what another mentioned above. It is important to have master cutoff switches for both battery banks. That is the only way to keep "phantom loads" from draining them. Also, with all systems shut down, and the master switch open ("Off"), you can temporarily place an ammeter across the switch and know that something is still drawing current somewhere.

I found some of these switches on Ebay® with postage included from an Australian dealer of parts for boats much cheaper than the price on the shelf at camping supply places. Do a search on Ebay® for "battery disconnect switch" and "battery cutoff switch", so you can get some ideas. The ones I got are rated at 450 amps, if I remember correctly.
Title: Re: 4104 Owner Battery Question
Post by: Kevin on April 27, 2013, 08:55:25 PM
Hey Jon,

My '04 came from previous owner with (2) 8-D start batteries and (6) deep-cycle 12 V house batteries. I've replaced the 8-D's once and swapped out the 12 V deep cycles for 6 V deep cycles, which I'm told yield greater amp hours. I've been pretty happy with this set-up.

Kevin
Title: Re: 4104 Owner Battery Question
Post by: Kevin on April 27, 2013, 08:58:22 PM
Jon,

Forgot to mention... my coach too is equipped with master cut-off switches on both the start and house batteries. It is cheap insurance and I usually switch 'em both off if I don't operate the Ol' Mare for more than a couple of months...

Kev
Title: Re: 4104 Owner Battery Question
Post by: luvrbus on April 28, 2013, 07:01:45 AM
Texas Industrial Electric has everything one need to make a good battery disconnect system I would not be buying the junk from WM myself check out the new battery separators they will automatic disconnect from a low battery to protect a good battery pretty neat then they sell good manual disconnects.

You get what you pay for that is not a place to cheapen up IMO www.texasindustrialelectric.com (http://www.texasindustrialelectric.com)
Title: Re: 4104 Owner Battery Question
Post by: gus on April 28, 2013, 07:46:38 PM
Siberyd,

That jumper is probably the PO's easy way to connect house and start batts instead of using some kind of switch. Just a guess.

Kevin,

You don't need 8D starts in a 4104, way overkill. The original reason they were used was to run the huge fan for the heat/AC system and because the bus had a generator instead of an alternator. Gp 31s are plenty big for starts. They might be needed if you use the bus in super cold weather, but not otherwise.

House batts depend completely on your bus use and your house elect system, everybody has different needs.

I've used the cheap green knob batt cutoffs from WM for many years and had only one fail because of too much side load from the cable. I use them in every vehicle I own including farm tractors, probably 25 total. There is one knob type that comes apart when the knob is loosened, but the green ones stay together.

Title: Re: 4104 Owner Battery Question
Post by: Kevin on April 29, 2013, 09:43:07 PM
Thanks, Gus, for the info!!!

Those 8-D's are b@!! breakers to heave in an' out! Not cheap either... plus if I can shed a few additional pounds, I may be an eyelash faster on those Ol' 4104 w/6-71 uphills! Yeee-Haaaa!!! ;D

Kevin
Title: Re: 4104 Owner Battery Question
Post by: gus on April 30, 2013, 06:41:09 PM
8Ds also have the poorest warranties of any other batts. They simple are not necessary for a conversion, especially if you have converted to an alternator-an easy thing to do.

One good thing about a 4104, it will climb mountains all day long without overheating, you just have to learn to shift down into a lower slower gear and enjoy the scenery. There is one place coming SW out of Ruidoso, NM  where I drove it five-seven miles uphill in second and third at full throttle, never made one complaint.

If you lug it on hills it will overheat and die an early death.

I've crossed the Rockies and most other western mts numerous times plus all the eastern ones as well and never had a problem. I put 75,000 miles on it in five years.

My single complaint is that first gear is too high, always had to be careful not to stop on an uphill incline. It will go but it is murder on clutches.
Title: Re: 4104 Owner Battery Question
Post by: Kevin on April 30, 2013, 08:29:12 PM
Amen Brother!

We've had ours up to "dirt-bike-heaven" Kennedy Meadows here in SoCal quite a few times. It is up into the 7-8 thousand feet elevation nose-bleeder territory. I'm pretty much ground down into 2nd gear for a loooong ways there, and eventually even into 1st in order to bend 'er around this one ridiculously tight blind right-hand corner.

My buddy has a 2003 GMC DuraMax with Allison auto. He tows a BIG toy hauler... like 35 footer. I led the way up the hill at his request (I told him I'd be draggin' my behind at a snail's pace) but he insisted. After a bit I noticed that he fell behind. I wasn't ABOUT to stop 'cause it is bloody steep! Near the top there is a gas station/convenience store. Daughter Sarah and I stopped there - where it sort of levels off and you can actually upshift again - to wait for our buddy.

Wait we did. About 45 minutes. We were kickin' it in our camping chairs sipping soda pops when John finally showed up. Turns out his (then brand-new) Duramax Allison trans overheated three times on the climb up and he was forced to pull over and let 'er cool down. Heh, heh, heh.  ;D

The 1960 Ol' Dinosaur just mosied up, cool as a cucumber, dirt-bike trailer in tow.... Ahhh... It's life's little pleasures, ain't it?  ;D

Kevin
Title: Re: 4104 Owner Battery Question
Post by: gus on May 01, 2013, 02:28:36 PM
John probably could have prevented the overheating by shifting down, even ATs need to be managed properly.

I do this with my Allison in the mts, it is slow going but it works. I'm in no hurry, one gets to see more of the scenery that way!
Title: Re: 4104 Owner Battery Question
Post by: DaveNCari on May 06, 2013, 09:23:51 AM
Ok.....so....what speed do you downshift to 2nd?

And then 1st....

Dave
Title: Re: 4104 Owner Battery Question
Post by: Mex-Busnut on May 06, 2013, 11:44:49 AM
It isn't so much the vehicle's speed, but the engine's RPM that you consider for up-shifting and down-shifting.
Title: Re: 4104 Owner Battery Question
Post by: gus on May 06, 2013, 12:30:09 PM
Mine automatically shifts to 2nd at about 45 and 1st at 25 but I often have to manually shift it into 1st or by almost stopping.

45 is too slow for second because it quickly pulls down so I usually manual shift at around 50 to keep the roms up. It will overheat quickly in 2nd below about 35 on a hard pull.

However, my trans does not shift down as other 730s on the board do so my system may not work for you.
Title: Re: 4104 Owner Battery Question
Post by: chessie4905 on May 06, 2013, 06:38:33 PM
he wasn't assuming the trans temp shouldn't be higher than coolant temp?