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No I'm sure you should isolate the positive side as per Martin's wiring diagram but it's any other problems encountered from winching off the main / only battery on a Jimny with standard vehicle wiring still connected to that battery that is my concern!
Kirkynut
The underdog often starts the fight, and occasionally the upper dog deserves to win - Edgar Watson Howe.
I have lost track of whether you are talking about a single battery installation or a dual.
If its a single battery then you should definitely isolate the positive feed and isolate it as close to the battery as possible.
This is because if you isolate the negative to the winch you will have a long live cable running to the front of the car, this live is too heavy duty to fuse in the normal fashion. Therefore it represents a real hazard in the event of a frontal collision, this is because you will still have to have a negative connection to the chassis to keep the car running and in a collision the live could short to the car negative.
If you have two batteries with one dedicated to the winch you could, in theory, isolate the negative. This would be ok if the negative was not used for anything else and therefore was not connected to the chassis at the battery end. The positive feed from this battery is then "floating" and could be considered harmless in a collision. However as you have to charge this second battery somehow it is likely to be connected to the main battery live, even if this is through a split charger. Therefore there is still a live around that is referenced to the chassis and will still short out in the event of a collision. This live would typically be "fused" through the low duty split charge connection or alternator which would blow, protecting the car but destroying any intermediate electronics/wiring.
Martin
Martin
2003 M13 early KAP build.
3" Trailmaster lift with 1.5 Spacers on front
Customised winch bumper and roll cage
235/85R16 Maxxis Bighorns on 16" Rims, 4:1 Rocklobster, Rear ARB locker and on-board air
Corrected arms all-round, rear disks, Recaro seats and harnesses
I can see why you might be confused about if I'm on about a single or twin battery set up Martin, that's because I've been undecided.
I will use 2 though. There's not enough space where the original goes to put a Numax as I intend to use, so I may as well keep the original there and connect the two together to give that little (albeit the standard battery is little) extra power storage.
I think I will abandon the split charge idea and just connect the 2 together and run the winch off the both and will isolate the live as planned and advised.
I will have to do as suggested by Funkyjimny and just rest the batteries by leaving the car running to charge them back up between winching but believe from various other people's experiences, as on here and friends that the Numax will have enough in it for quite a bit of winching.
Like others that have kindly responded to this thread, I'll not be doing Chalenge events, just Green Laning and Pay and Play with the odd Club competition. I'll always be with others to get a jump start if I go to far.
It seems that as per Martin's original advice, the high amp fuses in the engine bay next to the battery won't have any cause to blow, the ignition one is rated for the alternator and I guess that even when that's working at it;s max it should not exceed that fuse (80amp).
My bespoke front winch bumper and off road armory rear bumper are on now and the cage goes on next weekend. Then next week I'll wire in the winch and battery and post some pictures of the next evolution of my Jimny!
Cheers for your help chaps.
Kirkynut
The underdog often starts the fight, and occasionally the upper dog deserves to win - Edgar Watson Howe.
I don't promise this to be the last question but hope it to be!
I have bought a nice big NUMAX battery to use for winching. I had hoped to use it connected to my normal small starting battery in the front.
However, people are warning me that due to the size difference, the rear (NUMAX) might not get the charge it needs and that I should either run 2 the same or only one.
I will NOT be using a split charge system, just charging them both constantly by having them connected together permanently.
What are your thoughts / experience.
What battery do you run in the front Martin? As I'm guessing when you are not winching if you run a standard small battery in the front like mine depite your split charge relay, your batteries are connected like mine.
My small old battery is in good condtion, although I had my suspicions about that recently as I have a starting problem which I have boiled down to a bad earth or the starter and not the battery / alternator.
Has anyone noticed I can't seem to do concise yet?
Kirkynut
The underdog often starts the fight, and occasionally the upper dog deserves to win - Edgar Watson Howe.
