Portable Jump Starter
Author
Discussion

1962

Original Poster:

131 posts

204 months

Sunday 6th November 2016
quotequote all
Any knowledge or experience on here

What's the minimum mAh to start a car from cold ?



TooMany2cvs

29,008 posts

155 months

Sunday 6th November 2016
quotequote all
1962 said:
Any knowledge or experience on here

What's the minimum mAh to start a car from cold ?

Not that particular one, but they're probably all much of a muchness. They're really just a battery (of varying capacity), capable of delivering a good jolt of 12v via some short jump leads.

Minimum current and minimum battery size needed depend entirely on the vehicle and on just how flat the battery is.

I've used 'em once or twice, and they seem to do the job - better than I was expecting, tbh.

Riley Blue

23,205 posts

255 months

Sunday 6th November 2016
quotequote all
I have one, not the same but similar and it is great at starting my Riley 1.5. The only possible snag is that the orange box on the positive lead gets very warm with repeated use and on mine its casing shows signs of melting.
This is the one I have, it cost around £45 a year ago:

http://www.ebay.co.uk/itm/like/302115283332?lpid=1...

TooMany2cvs

29,008 posts

155 months

Sunday 6th November 2016
quotequote all
Riley Blue said:
I have one, not the same but similar and it is great at starting my Riley 1.5. The only possible snag is that the orange box on the positive lead gets very warm with repeated use and on mine its casing shows signs of melting.
This is the one I have, it cost around £45 a year ago:

http://www.ebay.co.uk/itm/like/302115283332
I'm guessing it's a fuse in there? What rating?

rswift

1,181 posts

204 months

Sunday 6th November 2016
quotequote all
I got this earlier in the year, came in a neat flight case/box which slips under the seat.

I've only used it anger once, but that was several starts of my 4.0L Jeep....

Great bit of kit..

https://www.amazon.co.uk/dp/B01AHYB8SG

Riley Blue

23,205 posts

255 months

Sunday 6th November 2016
quotequote all
TooMany2cvs said:
Riley Blue said:
I have one, not the same but similar and it is great at starting my Riley 1.5. The only possible snag is that the orange box on the positive lead gets very warm with repeated use and on mine its casing shows signs of melting.
This is the one I have, it cost around £45 a year ago:

http://www.ebay.co.uk/itm/like/302115283332
I'm guessing it's a fuse in there? What rating?
This is what's in there.


TooMany2cvs

29,008 posts

155 months

Sunday 6th November 2016
quotequote all
Riley Blue said:
This is what's in there.

<peers> Transistors?
OK, now I'm at the edge of my electronics knowledge. What would they be there for?

battered

4,088 posts

176 months

Sunday 6th November 2016
quotequote all
TooMany2cvs said:
Riley Blue said:
This is what's in there.

<peers> Transistors?
OK, now I'm at the edge of my electronics knowledge. What would they be there for?
That's weird. Can you get the codes off them, so we can look them up? Also a better photo showing how they are wired may be helpful. My guess is that they are diodes to protect the circuits if someone reverse connects them. You might need 4 in parallel to cope with the heavy currents. A closer pic will show this.

Riley Blue

23,205 posts

255 months

Sunday 6th November 2016
quotequote all
Sorry for phone pic, here's a better one (I hope)


battered

4,088 posts

176 months

Sunday 6th November 2016
quotequote all
I only got one of the codes to pop up on a database, it's a low resistance resistor. My guess is that it's there as a current limiting network so stop the cable frying if you do something stupid like subject it to a dead short. The fact that it gets hot supports this.

RONV

655 posts

163 months

Sunday 6th November 2016
quotequote all
I bought one from POWERSPARK works well and you can use it to recharge your phone and cameras always take on my classic runs overseas

finlo

4,453 posts

232 months

Sunday 6th November 2016
quotequote all
battered said:
I only got one of the codes to pop up on a database, it's a low resistance resistor. My guess is that it's there as a current limiting network so stop the cable frying if you do something stupid like subject it to a dead short. The fact that it gets hot supports this.
They are there to stop anything nasty happening should you connect it arse about face.

Trabi601

4,865 posts

124 months

Sunday 6th November 2016
quotequote all
I bought one of the cheap Chinese ones from Banggood, or similar.

Seemed to be fine - but once discharged, it would never charge again.

Of course, because it was stuck in the boot of the car, it only came out when I needed it, which was after the opportunity to return had passed.

Andrew Gray

4,974 posts

178 months

Sunday 6th November 2016
quotequote all
I have a Micro Start which i believe was the original one is been very useful and will start the V8 Tuscan so works very well been used a lot as a power source when re wiring the car and testing as we went along
Andrew

battered

4,088 posts

176 months

Sunday 6th November 2016
quotequote all
Trabi601 said:
I bought one of the cheap Chinese ones from Banggood, or similar.

Seemed to be fine - but once discharged, it would never charge again.

Of course, because it was stuck in the boot of the car, it only came out when I needed it, which was after the opportunity to return had passed.
This is what usually happens with the ones based on a lead acid battery. You forget to charge them, they need charging once a month or so, after 6 months they are dead and a new battery costs more than the thing is worth.

Trabi601

4,865 posts

124 months

Sunday 6th November 2016
quotequote all
battered said:
Trabi601 said:
I bought one of the cheap Chinese ones from Banggood, or similar.

Seemed to be fine - but once discharged, it would never charge again.

Of course, because it was stuck in the boot of the car, it only came out when I needed it, which was after the opportunity to return had passed.
This is what usually happens with the ones based on a lead acid battery. You forget to charge them, they need charging once a month or so, after 6 months they are dead and a new battery costs more than the thing is worth.
This wasn't lead acid and was only days out of the returns policy - so, 60 days old, I think?

ruggedscotty

5,989 posts

238 months

Sunday 6th November 2016
quotequote all
Schottky diode.

its a low resistance diode designed to prevent reverse polarity connection. Id imagine get it connected wrong then you would have a possible battery popping and dumping nasty electrolyte everywhere.

Its there for safety

mgv8

1,657 posts

300 months

Monday 7th November 2016
quotequote all
DBPOWER 600A Peak 16500mAh is the one I have.
This will start a very dead 2L diesel or upto 3L petrol so me 1725cc car will be and easy one.
You need to read how to use them. Two main things is only crack over the car for a few seconds or it will over heat. You then let it rest and try again.
It will stay charged for ever but you dont want to run it fully flat. Always change it after use.

I would go as big a you can unless it will be with you all the time.
Also dont go to cheep there is a LOT of power there and if it goes wrong it will way bigger than an S7 phone!

TISPKJ

3,775 posts

236 months

Monday 7th November 2016
quotequote all
I bought one very similar not lead acid from the fella that is always at the Brooklands events, I paid about £85 for the middle one which from memory does 4l diesel or 6l petrol engines, fits in the glovebox, needed to use on first day of holiday on my 5.7l boat, incredibly started it up numerous times no problem, just make sure you disconnect once engine fired up.

laters

324 posts

143 months

Monday 7th November 2016
quotequote all
Ive had a FLOUREON branded starter pack for a while now. Its always in the storage compartment in the boot floor along with a few other odds and ends.
It lives in a flame retardant lipo safe storage bag just to be on the safe side.

Its started everything I have ever asked it to & is handy to power 12v pumps or lights when working on the car without the need to extend cables to the main car battery.

In that period of time I have recharged it a couple of times. Every so often will get it out of the boot and use the inbuilt usb sockets to give the battery pack some use. It will then be recharged after the battery pack has been used.