| Author |
Message |
Steven D. Braud (Steve77amg)
Registered Member
Username: Steve77amg
Post Number: 33
Registered: 5-2005
Posted From: 63.232.249.10
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 26, 2006 - 8:46 am: | |
My question is about batteries. The two 8D’s in my ’77 AMG have died and need to be replaced. I have read on this board that some people use group 31 batteries. How many does it take to replace two 8D’s? Also the company that did my bus conversion set up the coach twelve volt system to run off of the generator battery and the start batteries. BTW my bus came from the factory as a twelve volt system instead of the usual 24 volt system. Will the group 31’s be a better choice for boondocking than the 8D’s? I live in central Arkansas so it can get really hot in the summer and very cold in the winter. Thanks in advance for any and all suggestions.
Steve 77amg |
JR Lynch (Njt5047)
Registered Member
Username: Njt5047
Post Number: 39
Registered: 7-2006
Posted From: 69.132.238.127
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 26, 2006 - 9:52 am: | |
I use two group 31s for cranking batteries for my 6V92. Probably the only place where a problem would occur is the max cold weather cranking amps. Keep the capacity to parallel your house batteries and you'll have a backup crank source.
I'd be separating the genset and house batts from from the cranking battery system. You're going to be walking one day.
I don't think group 31s are a better choice, just another choice. 8Ds offer a lot of battery power.
If you use your coach in cold weather, I'd probably stay with the 8Ds. Although 4 31s would do the same thing. Just more batteries to maintain and buy.
Your 12V coach allows you to pick what you want. You can use 1, 2, or whatever....since they are wired in parallel. Still 12V. Just match the cold crank amps.
I mounted two g 31s in the engine compartment for cranking, and left the orig 8Ds and Vanner in place for house batts. Have another 12V batt for genset. Something's gonna start. They can all be charged from the genset.
JR |
Gus Causbie (Gusc)
Registered Member
Username: Gusc
Post Number: 181
Registered: 11-2005
Posted From: 63.97.117.33
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 26, 2006 - 4:47 pm: | |
Steve,
Glad to see you have the bus back on the road. I use two 31s for the bus and two more 31 Deep Cycle for the house. I got them at Sams in LR. Conway WM may have them but our little WM here doesn't. They are much easier to handle, I'll never go back to 8Ds.
If you're going to boondock you probably need more than two deep cycle but four will almost fit into the same space as one 8D.
I have a simple "Green knob" battery cutoff on each battery so I can use any combination I want. You can even use the deep cycle 31s as a boost for the bus in an emergency. Disconnect the two bus batteries while boondocking to make sure you can start the engine.
I have a small lawn tractor battery for my gen but can hook it up to any or all 31s with a switch to a power relay when it is too weak in cold weather. The only reason I have a separate battery is because my Onan gen has a small alternator on the flywheel and requires that a battery be hooked to it at all times. Otherwise I would just use the bus batteries to start it. |
Dale Waller (Happycampersrus)
Registered Member
Username: Happycampersrus
Post Number: 235
Registered: 7-2005
Posted From: 172.133.5.225
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 26, 2006 - 6:48 pm: | |
I have my block heater "hard wired" in with my shore power so a few hours before we are ready to leave I flip a switch inside the coach. I also can use the genny to preheat the engine when boondocking.
I have used group 31s for 4 years now without any troubles.
Those large 8Ds were used for the bus heat and air conditioning. Those batts were also needed if the equipment would sit outside over night with no starting aid and you had to have a reserve capacity to get the Detroit to start.
I am like Gus, I will never go back to the large 8d batteries. If you get in a bind with a bad group 31 you can get one easier than a 8D.
Dale |
Steven D. Braud (Steve77amg)
Registered Member
Username: Steve77amg
Post Number: 34
Registered: 5-2005
Posted From: 63.232.251.97
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 27, 2006 - 7:28 am: | |
Thanks for the responses guys. The company that converted my bus did not put in a house battery system. Instead they installed a switch so that you can boondock off of the gen batt or off the start batts or run off of both sets of batteries. A cheap way of getting around putting in a house batt system!! I don't plan on doing a lot of boondocking but since I have to replace the 8D batts I wanted to explore the options. Thanks again for the input.
Steve 77amg |
Bob greenwood (Bob_greenwood)
Registered Member
Username: Bob_greenwood
Post Number: 133
Registered: 7-2006
Posted From: 65.150.46.210
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 10, 2006 - 1:39 am: | |
Steve, you have a good set-up.all you have to do is add however many batterys you want to your generator battery |