Jump starting Motorcaravan

corktina

prompted by the thread on the cold killing batteries, I checked my Camper and the battery was a bit low, needing the charger starter to start it.

Not a problem but what it made me wonder is, can I jump start the van from the Leisure battery which had more charge in it than the Starting Battery.

zambo

Hi
It depends on what type of battery you have,some of the deep discharge leisure batteries would be destroyed by the current used to start a van however some of the newer type can be used safely.I have an Elecsol battery which claims to be usable as a starter battery and many people just use a large truck battery instead of a leisure battery so they are ok.
Best to see what battery you have and check on the label or the net to see if it is suitable.
Yours Zambo

I've done it on rare occasion with Elecsols.
A better solution is link the batteries and charge the starter slowly from the charged leisure batteries then disconnect once the starter holds 12.4v and crank.

Generally speaking though if you can't crank the engine it's time for a new starter battery; flattening it like that or turning the engine without cranking will make short work of it. I'm in the same boat myself I'm amazed I can turn the engine some days the starter is so low, soon as I have to jump myself I'm just replacing the battery.

corktina

i'll just use the charger starter now and again to keep it going and put the built in charger on for the leisure battery

Thankls

Yeah I'm doing similar when I have the chance. Didja fix yer fridge yet?

odds_on

Sir Liamalot wrote: »

I've done it on rare occasion with Elecsols.
A better solution is link the batteries and charge the starter slowly from the charged leisure batteries then disconnect once the starter holds 12.4v and crank.

Generally speaking though if you can't crank the engine it's time for a new starter battery; flattening it like that or turning the engine without cranking will make short work of it. I'm in the same boat myself I'm amazed I can turn the engine some days the starter is so low, soon as I have to jump myself I'm just replacing the battery.

I thought it was a camper you were in.

:rolleyes: not a whole lot of difference I suppose other than getting away with the holes in my hull. I often imagine it like a sailboat because I'm constantly on top of the upkeep out of dock. I hate rattles...better than squeeks mind, but neither survive long round here.

corktina

Sir Liamalot wrote: »

Yeah I'm doing similar when I have the chance. Didja fix yer fridge yet?

fridge has been at the menders for weeks if not months..... 2 weeks ago I told the fecker to just bring it back if he wasn't going to fix it.......not a sight of him......

Sorry to hear it, that's a pain.
Could you tell him if he doesn't bring it back soon you'll have to charge him for leasing it from you?

Aidan_M_M

Sir Liamalot wrote: »

Sorry to hear it, that's a pain.
Could you tell him if he doesn't bring it back soon you'll have to charge him for leasing it from you?

Oh feck! As Liam says , no pay no fix!

odds_on

Aidan_M_M wrote: »

Oh feck! As Liam says , no pay no fix!

And never lend a book to an accountant or it will be ages before you get it back.
--
--
They're good bookkeepers.

corktina

Sir Liamalot wrote: »

Sorry to hear it, that's a pain.
Could you tell him if he doesn't bring it back soon you'll have to charge him for leasing it from you?

i'm considering buying a new one

corktina

got it back, I'd say he never even looked at it

Rubbish.

corktina

huh?

That is rubbish behaviour from your technician.

corktina

and I have to re-install it myself too....

Re-install it half-working? Madness!

paddyp

I might be selling a dometic one soon as I bought two identical ones my brother was supposed to be taking one but thats looking unlikely now. I'll give you first refusal.

You going down the compressor road then Paddy?

corktina

paddyp wrote: »

I might be selling a dometic one soon as I bought two identical ones my brother was supposed to be taking one but thats looking unlikely now. I'll give you first refusal.

thanks...what model is it?

corktina

anther related question...if I link the two batteries with jump leads, can I charge both with the onboard charger from the mains?

Yes indefinitely if they're the same age, type and make.
Periodically it's ok for as long as it takes to complete the charge but more than a few hours is a bad idea.
If they're two different types of battery expect to undercharge one.

Split chargers;
http://www.smartgauge.co.uk/smartbank.html
http://www.bluesea.com/products/7601/m-Series__Automatic_Charging_Relay_-_12_24V_DC_65A

corktina

just to keep them alive during the winter, a bit of charge now and again is my plan

Yeah that'll work ok but if the leisure battery is on constant float then dropping into charge cycle every time you want the starter topped up will reduce the leisure battery lifecycles from charging a battery at less than 5% DOD.

Best ways to do it are;
Two chargers & two batteries,
One charger split relay two batteries.
One charger one battery (at a time).
Two bank charger
One charger two batteries after allowing both batteries to drop to below 12.6v.
Take them inside where they'll be warmer and won't self-discharge as quickly.

You only need to use one jump lead between the positives assuming the ground is common as most campers are wired. I think yours is IIRC.