In message , "Dave Plowman (News)" writes
I had a nice chat with the owner of Camco a few years ago (when they were in Ardwick), he was of the similar opinion but he makes a nice living testing them. It's the black box mentality which has killed off the skill in many garages, the old guard are scared of the electronics and the young guys can't be bothered working it out. I do know garages that are superb with the electronic stuff but they are in a definite minority.
Mike P gurgled happily, sounding much like they were saying:
I was beginning to suspect as much.
Provided they've checked the more likely things first. But sadly few 'mechanics' understand how EFI works (or indeed any electrics) so just scatter new parts around.
Or you could the find the other fault that you're going to have to find anyway.
Well, it is the season of goodwill!
;-)
Chris
Adrian formulated the question :
Absolutely not my experience of them. Mine has a 7amp/hour battery and the only thing it ever successfully managed to start was a 600cc motorcycle. It would not even crank either car over, never mind start one. I would not expect a 7amp/hour unit to be even able to, where they get the 700amp rating from I don't know. The big battery on the larger of my vehicles is only rated 730CCamps and it is ten times the size.
Dave Plowman (News) explained :
Which is what they are good for.
The peak current has nothing to do with size.
Others have said they have successfully started vehicles with these. Of course it may depend on how deeply the vehicle battery was discharged - and if the reason for the original non starting was another fault.
It's linear to size for any particular battery type.
They're occasionally handy when the battery's nearly upto the job.
In message , Duncan Wood writes
Quality plays a massive part though. A cheap battery will not be able to deliver the same current as a good quality one of the same chemistry.
The small pack of Hawker Cyclon cells I have can crank and start my 2.2L petrol people carrier easily. Individually they're not much bigger than a D cell.
The trick is getting low enough impedance in the cell interconnects and the cables from the pack to the bus...
The cheap booster pack my friend has (which is theoretically more than four times the capacity) will only start it if I connect it and let it sit for five minutes or so, the boost leads are pathetically thin.
Ok. But then no car uses a SLA type like in those jump start packs.
Not that I'm aware of, but they're fairly common on small engines, bikes, small plant etc. Their CCAs aren't particularly larger than a conventional starting batterys & most of the packs have very small batterys.
My cheap Lidl one has cables the same size as starter motor ones.
In message , "Dave Plowman (News)" writes
I assume you've checked the diameter of the copper and not just the outer though? If it's the same diameter copper then it sounds like it's a good buy.
Yes - you can see the conductor at the crock clips.
In message , "Dave Plowman (News)" writes
Hmm, I may have to go and have a look when they next have them, are you happy with it?
I've not seen them on sale since I got that one - several years ago now. It looked identical to ones Halfords were selling at twice the price. The battery on it is now well past its best - so can't be used for jump starting anymore. But this happens to all of them regardless of price.
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