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Yankee802
01-24-2009, 10:58 AM
I don't have to now, and hope to never have to, but just in case and for others who don't know, how do you jump start the bus if the chasis batteries are low/dead? I've never jump started anything with multiple batteries, so I figured I'd ask.

Geoff

Jeff Bayley
01-24-2009, 02:07 PM
Geoff-

All the Prevost's I've seen have two large post surface mounted near the chassis battery area and usually accessed throgh the passenger side engine bay door. They have two rubber cover insullating them against accidental short. Red and Black rubber covers. If your coach is older, maybe they didn't have that then. In that case, get a voltmeter and poke around on your terminals until you get 24 volt reading and not 12 volt (don't even think you could get 12 volt on any combination of a P and N terminal). Make a note or a diagram so you know which post to use if/when they are dead. You typically want to the cables at the far ends of the series and not just on one battery.

Yankee802
01-24-2009, 02:50 PM
Thanks Jeff, now that I'm thinking about it, what could you use for the source? Can a car jump a bus, would it have enough cranking amps?

Geoff

Joe Cannarozzi
01-24-2009, 03:09 PM
Fire up the generator plug in the chassis charger and wait 1 hr.

Jeff Bayley
01-24-2009, 06:13 PM
I get flack for long postings so exit now if your short on time.

Joe- Geoff's bus must not have a built in charger. His by-line list his bus as 1984. I came back and logged in because I was in the shower and thining about electrica issues. Maybe because the batteries died on my butt plug....I regress. Anyway Geoff, I relaized that part of the answer I omitted was indeed the sourse. Now understand, I'm the same guy just posted a question about the details of how the 12 volt shout off switch in the same engine bay area specifically works. I guess I'm "Dumb and Dumber" on some things and "No so dumb" on others but there are plenty of coach owners here that should have chimmed in on this one. Where is everybody ?

Geoff- If your coach doesn't have the built in 24 volt charger, then Joe's answer could still work if you have an external 24 volt charger and an extension cord. I have not found an affordable 24 volt charger. The mechanics roll round type are pricey and I bought one of those on C.List for $150 and consider it a steal. The ones built into most of our coaches are much more compact as you might expect. The size of a toaster. But they are like $400. Mine stopped working about a year ago and I could not find a "deal" on one out there. I removed that charger and took it to an electronic repair place local to me that fixes computers, TV's and just about anything. Old timer electonic engineers in they're that poke around on your problem with an meter until they identify it down to the conponent level. They changed the rectifiers and the bill with labor was like $75. If anyone's built in charger fails DON'T replace it or discard it. It can be repaired like mine. If you want a new one, mail you old one to Geoff or me or to this place in Sarasota called IST (Insustrial Standard Technology). They will look at ANYTHING and if they can't fix it, they only charge $25. Bargain.

What follows can be used to find all sorts of stuff and bargains for anything you can imagine.

Geoff- Go to a web site called www.craigshelper.com You can't use it with Internet Explorer's browser for some reason. You might need to download a 2nd browser called Fire Fox or Mozzila. http://www.mozilla.com/en-US/firefox/ Free and a very small file. This web site allows you to search mulitple cities with one search string instead of going city by city around your area. Much faster and efficient way to find things. For small things that can be shipped, I have used it often to find bargains. I can usually find what I need in my home state. I bought at least a half dozen pair of name brand sunglasses using that tool around Florida and paid the people with paypal or mailed them a check and they mailed me the goods. You can serach by "exact phrase" or other criteria. It's not hard to use. Just get the feel for it by testing it out.

Search across all of Craig's List in the cities (or entire states) of your choice and it will return results without you having to go city by city. Put in the words "24 volt charger" and also try "24 volt" and variations. It might show up under the "tools" catagory" or it very likley will be in "Boats". You can narrow your search to a specific catagory if you want and you have the optioun to search "Title Only" or the entire posting. You want "Title Only" for this search or you might get a bunch of cordless tools by putting "24 volt". Tinker with it a while and you'll get the hang of which optious to choose depending on how specific an item your looking for. I recall finding compact 24 volt marine chargers for large yachts under the "boating" catagory but you never know if someone might post this under "tools" or "general" or whatever. Your better off trying several different search strings and searching not narrowing your search to one catagory. If you need help, just email me, tell me what city or state your in, and I'll do the search for you and find you one lickity split and email you the results and a list of chargers. You'll probabley find one that is meant to be surface mounted but there's not reason you can't put a plug on the end and use as needed and put it away in the bay the rest of the time.

Kevin Erion
01-24-2009, 08:39 PM
Geoff,
I have a like new Deltran 24 Volt Battery Tender, I installed it on my 99 Marathon and had a few funny things going on with the isolator, I think. Anyway Marathon does not recommend a charger so I took it off. I will look on Monday what they sell for and sell it for 40% off retail if you want it.
Let me know.
714-342-8588

Joe Cannarozzi
01-24-2009, 08:43 PM
Question

What will happen if you try to charge a 24 volt system with a portable 12 volt charger.

Will it work but just take longer or do damage to the charger?

Jeff Bayley
01-24-2009, 10:39 PM
Joe- I tried it on more than one occasion and nothing happens except it might get to 12-14 volts max if your batteries were below that. It didn't hurt my chargers. What you COULD do in a pinch is disconnect the jumpers that series the batteries together to make it into 24 volts and charge each one seperatley, then reconnect and start.

I don't think there is a way to use daisy chain two 12 volt cars to make 24 volts without having to let the smoke out of the cars electrical system as an aside.

If you have AAA for RV or Good Sams or any roadside service and you needed a jump, specify that you need a roadside assistance vehicle equipped with 24 volt jump. I think 3/4 of them or so all have this anyway (guesstimate)

merle&louise
01-24-2009, 10:44 PM
I don't understand the need for an additional chassis battery charger. If there are battery chargers in the inverters(mine has one so I assume all of them do) why not just wire the inverter/charger to the chassis batteries thru a battery merge switch?

Alek&Lucia
01-24-2009, 10:56 PM
Geoff,
I have a like new Deltran 24 Volt Battery Tender, I installed it on my 99 Marathon and had a few funny things going on with the isolator, I think. Anyway Marathon does not recommend a charger so I took it off. I will look on Monday what they sell for and sell it for 40% off retail if you want it.
Let me know.
714-342-8588

Kevin,

I had before on previous coaches, and also have now Deltran installed, and it is working perfect.
Very happy with the unit,

Alek

Yankee802
01-24-2009, 11:24 PM
Jeff, that is a cool resource, thanks! I hope to never need a jump, but if I did, I would probably call my roadside assistance provider. Here is another question then, could a semi give us a jump?

I know I always have a lot of questions, I'm the kind of guy that likes to have backup plans for any occasion, if possible. :)

garyde
01-24-2009, 11:37 PM
I don't understand the need for an additional chassis battery charger. If there are battery chargers in the inverters(mine has one so I assume all of them do) why not just wire the inverter/charger to the chassis batteries thru a battery merge switch?

Hi Tuga. :D All of my previous Coaches were designed to be able to jump from the Coach Batteries if necessary. Prevost with the Convertor companies do not do this as far as I know. Liberty has a built in Chasis Battery Charger which you can turn on if necessary either using shore power or Generator Power. :D
We also have a seperate Battery for the Generator so it is independant from the other batteries.:):p

Jeff Bayley
01-25-2009, 12:17 AM
Geoff-

Sure; a semi could jump you if it used a 24 volt starting system. That (and RV's) is probabley why the majority of roadside assistance and two trucks and the sort have 24 volt jump sources. If you don't want to get a small portable type 24 charger, and assuming you've got spare bay space, you might be able to keep two charged 12 volt car batteries and put those together in series and get 24 volt. I think most our coaches use 4 batteries series together, not 2 so don't know if two would give you the cold cranking amps you need. I'm a little bit like you and I have managed to collect a number of portable generators and carry a 3,500 watt and a Honda 2000 watt and also a Yamaha 2,600 watt with me. I haven't dry camped enough and I'm still playing with them to which I need for what but the 3,500 watt Kipor (a quiet run inverter gen like the others but a less expensive) seems to be the one that is most useful. Most of these generators have built in 12 charges that use a plug in connector with medium size clips on them. I also keep a portable 12 volt charger that goes up to 25 amps that could run off the aux generator if needed and I'm tinkering around with using that to keep the house batteries topped off when I'm boondocking and don't need the roof airs on (which would require the main gen unless I only need one then the portable 3,500 Kipor works through the shore power cord. I park on city streets sometimes. Sometimes in busy areas. Downtown, South Beach, New York and I've slept with the parking lights on for good measure and in the AM the coach batteries were too dead to start the coach. Turning the built in 24 volt charger on (the one put in by the converter, not the suggestions for you) for only 15 minutes was all it needed to charge and fire. That one Kevin has sounds suitable and as long as your generator starts and you have an extension cord, your on your way.

Did you find the jumper posts in your bay and also, did you tinker with the Craighelper to search for any goodies (charger or otherwise) you need. Hey, Kevin. I know you and your kids all ride dirt bikes I think. You can use that Craigshelper to find motorcross gear that is like new or brand new as they keep outgrowing their stuff if want.

dalej
01-25-2009, 07:41 AM
We had to jump our bus back in the fall of 98 when our chassis batteries were on their last leg of use. We looked at the diagram in that area and seen which post were for 12 volt and hooked our jumpers to them and then to our jeep. We ran the jeep at a pretty high rpm for a while, maybe 15 minutes before it started.

jello_jeep
01-25-2009, 09:09 AM
My Marathon has a switch on the dash to join the house to the chassis for a jump.. LOTS of power available there!

Joe Cannarozzi
01-25-2009, 09:27 AM
Dale thank you that is what I thought.

We do not need to spend 400 bucks for a 24 volt charger for the chassis but rather 2-12 volt battery tenders hooked up correctly will do the job fine:)

Denny
01-25-2009, 10:09 AM
You can buy a 24 volt Battery Tender from Blue Spruce Aircraft (and other suppliers) for about $80. I recently bought a one from Blue Spruce. Two 12 volt Battery Tenders will cost that much and one 24 volt is much easier to use than two 12's.

Yankee802
01-25-2009, 10:34 AM
We had to jump our bus back in the fall of 98 when our chassis batteries were on their last leg of use. We looked at the diagram in that area and seen which post were for 12 volt and hooked our jumpers to them and then to our jeep. We ran the jeep at a pretty high rpm for a while, maybe 15 minutes before it started.

This is good to know it a pinch, being our toad is a Jeep. :)

Jeff Bayley
01-25-2009, 01:26 PM
Dale- Are you saying there is way to connect 12 volts to the 24 volt battery array and have it charge up the 24 volt bank ?

dalej
01-25-2009, 02:44 PM
If you look at the diagram in the back you'll see where the 12 posts are. This is where I hooked up my jumpers from the jeep.

If you don't have a diagram you can use a volt meter and find them.

Joe Cannarozzi
01-25-2009, 03:16 PM
What your doing is charging 2 of the 4 batteries. 2 that are paralleled (pos to pos & neg to neg).

So in effect it is 12 volt charging 12 volt.

Yankee802
01-25-2009, 03:23 PM
As long as it's enough to start the engine and the engine can finish charging. :)

Darl-Wilson
01-25-2009, 04:31 PM
Here is the Guest Charger a lot of us use and it has Tom's (Truk) diagram (http://forum.prevostownersgroup.com/showpost.php?p=21394&postcount=55). This has 2x12V leads that will charge and maintain the batteries. It can be permanently attached and then forget about it. My only caution is to disconnect from 110V when you start the engine. If you want more info you can call me (info in Dale's map). This is the best money you will spend...less than a hundred bucks at Hodge's Marine.
(http://www.hodgesmarine.com/ProductDetails.asp?ProductCode=GUE2610A&click=19)
Darl

Darrell McCarley
01-25-2009, 04:58 PM
I use the GUEST PRO CHARGER 12v/24v (2611A) marine all weather 10amp charger for a 24v charge. Truk posted instructions for wire connections to the batteries and using the engine heat electrical outlet in the engine compartment for power.

Darl-Wilson
01-25-2009, 05:20 PM
Darrell, I just posted above you links to the Guest Charger which you are referring and to Tom's post on the wiring.

I have the same Guest charger you have and it works great. I just forget about it until I do a 'pre-flight' and unplug the charger in the engine compartment. It is wired into the engine heater junction box with a on/off switch for the block heater. Never a problem and never a dead battery.

Darl

rodburtonmusic
03-31-2009, 03:14 PM
I just picked up a device called a Rescue 2000. It's a portable jump kit that can handle 12 and 24v applications. My coach was sitting on 4 pretty dead chassis batteries...it fired it right up.

Got it through Batteries Plus...and it was only ~ 140$. I'll carry it always.

dalej
03-31-2009, 03:31 PM
http://www.youtube.com/watch?v=_fLV3Jb62oo

It just looks like something everyone should have. Thanks for the info on it.

Maybe we should see if there is enough interest to put together a order for delivery to Oklahoma City.

Jon Wehrenberg
03-31-2009, 03:47 PM
That is a great idea especially for those with a 12V house system or a 24 volt house system with the house batteries too far away from the chassis batteries to use jumpers.

If you have a chassis battery charger it should not be necessary, but if your chassis batteries are near the end of their life no charger will change that.

Joe Cannarozzi
03-31-2009, 06:52 PM
Hey Rod it is about time.

A month or so here and you will be astonished what you will pick up.

Welcome aboard.

rodburtonmusic
03-31-2009, 08:09 PM
Hey Rod it is about time.

A month or so here and you will be astonished what you will pick up.

Welcome aboard.

Thanks Joe...you kept telling me...I'm just a little slow sometimes :)