Battery Cranking power needed to start an R

[paz]

Hello all,

My R has chewed another battery, and prior to getting it replaced I went out and bought a battery box (one of the jump start type ones with leads attached).

Just my FOOKING luck that the battery doesn't appear to provide enough charge to turn over the car, its just doing that ''click... click'' thing that I'm sure people have heard themselves before.

This is clearly GAY, so before going to tear halfords a new arsehole, I need to know what the bare minimum is that people would recommend, I think the battery box has 400amps peak crank power if that sounds right? Or at least what the standard battery put out originally.

Alternatively, could this be because my actual battery is so dead that a battery box isn't the answer and doesn't have enough power to turn the car over? Its been flat for a few days because I don't get chance to drive the car as much anymore

Cheers

Paz

p.s. yes the battery box is fully charged, just before anyone asks

 

[AJ4]

that crank battery should be plenty. I'd say you werent getting a good connection though, check and see if any of the ( crock clips I presume ? ) are getting hot.

possibly the already flat battery is drawing too much power from second battery, so disconnect the flat battery and see if you can start the car on just the crank battery.

 

[stumo]

You get a better cranking action from putting the neg onto the engine rather than the battery. there's no logical reason but you do.

As Ross says that battery should be adequate.

Check all connections, ie on the starter and the earth on the engine etc, if either is bad it will appear that you have a "flat battery" as not enough power will be transfered

 

[paz]

I'll give it a go tonight at starting directly from the jumper battery.

To be honest I think the actual car battery is knackered, as it doesn't appear to be holding charge properly - its been fully discharged a few times and I know they don't like that.

Never had any problems with earths etc before, but I'll give that a go if this doesn't work.

Cheers both

Paz

 

[pulsarr]

get a new battery
minimum volts needed to start one are like 12 maybe a little less

 

[sypher]

Minimum starting Voltage......11.0 V ( when starter motor engaged )
Maximum cranking Amperage....162 - 198 A ( providing no mechanical restrictions ie; siezing engine etc
Altenator output.....63 Amp's @ 13.5 Volt's @ 2500 RPM

 

[paz]

Cheers all, sorted it now.

My battery wasn't charging up enough in the period I left the car running for, because it was so flat to begin with. Took the car on a long motorway run and now all is well

The jumper box wasn't working because I hadn't earthed the negative on the engine, I'd connected it to the battery - just the way I've always done it.

So, all sorted now - thanks all for the info

paz