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Jumping a Battery

sealevel_ram
Explorer
Explorer
Is it OK to start a MH (or any other vehicle) with a battery charger attached?

In other words, use the charger as a jumper?

I have one of those portable jump starter things, but it doesn't appear to be working great.

Thanks.
"If the women don't find you handsome, they should at least find you handy." Red Green
20 REPLIES 20

tropical36
Explorer
Explorer
sealevel ram wrote:
Mile High wrote:
Does your coach have the switch that lets you combine coach batteries with chassis momentarily to give you a boost?


Yes, it does. Doesn't help with trying to start my engine. No change.

On further investigation today, I disconnected my chassis batteries, and both check out for voltage.

I must have a bad connection on the chassis side somewhere in my system? Or other suggestions to check out?

Anybody have this problem in past? My coach system appears to work fine.
I am connected to shore power (30 Amp), and my charger shows "float charging".

Something could be wrong here, as well, so why not take a jumper cable and connect your house and chassis batteries together.
If that gives you the boost you need, you can then trouble shoot the aux boost system....sw, relay....etc.
"We are often so caught up in our destination that we forget to appreciate the journey."

07 Revolution LE 40E_Spartan MM_06 400HP C9 CAT_Allison 3000.

Dinghy_2010 Jeep Wrangler JKU ISLANDER.

1998 36ft. National Tropi-Cal Chevy Model 6350 (Sold)

RayJayco
Explorer
Explorer
Sorry for the delay in response, the flu had us all down.

Red to dead, red to good, black from good to under the hood (some good metal and NOT the good battery terminal)

Only hook black to dead battery to keep from possibly harming the good battery...

Reverse for removing and as a note,
hook black to bad battery before hooking good battery black to metal.

First connect the jumper cables to the red or positive post of dead battery,
then connect the cables to red or positive post on good battery,
then connect the black cable to the black or negative post on the bad battery,
lastly connect the remaining other end of cable to something metal, such as a bracket, instead of connecting it to the black or negative post on good battery.

As Mr. Wizard said, connecting the black to the good battery can potentially cause a problem.
Reverse the order for removing.

This is for most batteries as I am not sure about the battery that wa8yxm is referring to...

Hope this helps. Be safe!
Inquiring minds want to know...

Mile_High
Explorer
Explorer
sealevel ram wrote:
Mile High wrote:
Does your coach have the switch that lets you combine coach batteries with chassis momentarily to give you a boost?


Yes, it does. Doesn't help with trying to start my engine. No change.

On further investigation today, I disconnected my chassis batteries, and both check out for voltage.

I must have a bad connection on the chassis side somewhere in my system? Or other suggestions to check out?

Anybody have this problem in past? My coach system appears to work fine.
I am connected to shore power (30 Amp), and my charger shows "float charging".
Yep, I don't think your problem is batteries.
2013 Winnebago Itasca Meridian 42E
2013 Jeep Wrangler Unlimited Sahara Towed

sealevel_ram
Explorer
Explorer
Mile High wrote:
Does your coach have the switch that lets you combine coach batteries with chassis momentarily to give you a boost?


Yes, it does. Doesn't help with trying to start my engine. No change.

On further investigation today, I disconnected my chassis batteries, and both check out for voltage.

I must have a bad connection on the chassis side somewhere in my system? Or other suggestions to check out?

Anybody have this problem in past? My coach system appears to work fine.
I am connected to shore power (30 Amp), and my charger shows "float charging".
"If the women don't find you handsome, they should at least find you handy." Red Green

Mile_High
Explorer
Explorer
Does your coach have the switch that lets you combine coach batteries with chassis momentarily to give you a boost?
2013 Winnebago Itasca Meridian 42E
2013 Jeep Wrangler Unlimited Sahara Towed

sealevel_ram
Explorer
Explorer
Thanks for all the replies.
Lots of good info.
"If the women don't find you handsome, they should at least find you handy." Red Green

2oldman
Explorer
Explorer
sealevel ram wrote:
Understand all that, but not the "Red to dead, red to good" part.
I think it means to connect one end of the red cable to the dead one, then the other end to the good battery.

I've jumped many batteries without paying attention to any sequence of connection and lived to tell about it.
"If I'm wearing long pants, I'm too far north" - 2oldman

sealevel_ram
Explorer
Explorer
MrWizard wrote:
sealevel ram wrote:
RayJayco wrote:


Red to dead, red to good, black from good to under the hood (some good metal and NOT the good battery terminal)


Can you explain this a little for the once-a-year mechanic?


connect the red-positive of the dead battery first
connect the black to car frame or motor mount, steel bumper etc..
NOT directly to the negative battery post of the batteries

the idea is to Avoid a possible spark at the top of the battery where hydrogen gas may be escaping

spark to hydrogen will cause an instant dangerous explosion


Understand all that, but not the "Red to dead, red to good" part.
"If the women don't find you handsome, they should at least find you handy." Red Green

MrWizard
Moderator
Moderator
sealevel ram wrote:
RayJayco wrote:


Red to dead, red to good, black from good to under the hood (some good metal and NOT the good battery terminal)


Can you explain this a little for the once-a-year mechanic?


connect the red-positive of the dead battery first
connect the black to car frame or motor mount, steel bumper etc..
NOT directly to the negative battery post of the batteries

the idea is to Avoid a possible spark at the top of the battery where hydrogen gas may be escaping

spark to hydrogen will cause an instant dangerous explosion
I can explain it to you.
But I Can Not understand it for you !

....

Connected using T-Mobile Home internet and Visible Phone service
1997 F53 Bounder 36s

wa8yxm
Explorer III
Explorer III
Something else tho know.. THis likely will NOT apply to any Car or RV made in the USA or imported into the USA on a regular basis but ...

Well last time I rand into it it was a stumper.

NOT ALL ARE NEGATIVE GROUND.

The stumper was positive ground so to jump it it had to be UNHOOKED from the truck and pay attentinon to plus/minus signes.. The Crew did not, And I had to jump both the stumper and the truck for 'em.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times

Passin_Thru
Explorer
Explorer
The Red is Positive, Black is Negative. Be sure to run Black to the engine, frame or - on battery. You can leave a charger hooked up and mos RVs when plugged in have a charger hooked to the battery. Pull the cables off, clean with a post cleaning brush, spray with battery cable protectant and return to service. You can pull batteries and have them tested at most Auto parts stores.

sealevel_ram
Explorer
Explorer
RayJayco wrote:


Red to dead, red to good, black from good to under the hood (some good metal and NOT the good battery terminal)


Can you explain this a little for the once-a-year mechanic?
"If the women don't find you handsome, they should at least find you handy." Red Green

RayJayco
Explorer
Explorer
Smitty had a good jump sequence.
The one that I have always remembered:

Red to dead, red to good, black from good to under the hood (some good metal and NOT the good battery terminal)

Only hook black to dead battery to keep from possibly harming the good battery...

Reverse for removing and as a note,
hook black to bad battery before hooking good battery black to metal.

I hope this helps someone!
Inquiring minds want to know...

shastagary
Explorer
Explorer
unless you have a real jump starter charger most the others do not work very good. i have one of these there older model bought 30 years ago and has always started any good running vehicle with a low battery i have used it on. has a real 200 amp boost. SCHUMACHER SE-3010