How many people winch with stock alternator? (1 Viewer)

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Hi guys, I did a search and found comments on both sides of the fence and I'm not sure what I should do. How many of you run a winch and still use the stock 80A alternator? If so, have you had any issues with bottoming out your crank battery and/or shortening its life? Slow running winch?

The Runva winch I have has a peak draw of 400A, but that would be at full load, no snatch block, etc. Worst case scenario. But even in a normal situation, the 80A alternator won't be pushing many amps on idle, so the battery must be carrying the load. I do have a hand-throttle; should I be using this when I winch? What kind of engine RPM is recommended?

By rights the winch shouldn't affect anything else in the vehicle (directly connected to + and - terminals, with switch) but I'm also getting some feedback in the rest of the system as some lights have blown and who knows what else has been affected. A bigger alternator won't help me here, but if I'm stressing the battery then the voltage to the rest of the car will fluctuate... Just a theory.

Just chasing your experience

Cheers,

Chang
 
Hand throttle is a nice feature, is very nice to bump revs up a bit for a little more amperage out of alt. The exact figures elude me, I'd guess 1500-2000 rpm should be capable of producing peak output when required. There may even be a diagram on mud here somewhere that will show you more precisely, and chances are someone will know offhand.

Bigger alt is a nice feature but definitely not required. Part of a batteries purpose in an automotive electrical system is to act as a shock absorber, usually takes a long, long hard winch to drop voltage far enough to be a problem. Which is not to say it wont take time for alt to top off battery again, but routine winching won't hurt anything. Battery type ie starting rather that deep cycle makes a difference, my interpretation is a starting battery is constructed with fewer larger plates that will deal with heat from high rate discharge and recharging better than a deep cycle which will have more thinner plates that will deal with a long slow discharge better.

Heat buildup in the winch motor itself can often become a problem first. A good thing to keep an eye on, can give the motor a quick pat to keep track of temps, be warned it may be capable of burning you, which is definitely too hot. But again, that would be a long hard pull. Does depend on ambient temps also. Being mindful will avoid this scenario, keep an eye on you connections as well. Any high resistances (loose, dirty, corrosion..) will heat up quickly.

Thats all fine and good, but more to the point, lots and lots and lots of stock alternators are winching all around the world right now. Don't worry too much about it.
 
What's the Duty Cycle of the Runva winch?

That will tell you how long and hard you can pull with it.

Since I am mostly a flatlander, my winch is a Badlands 12K and its duty cycle is 45 seconds of pull with 2 minutes off time. I hit it all the time when I use it, but it shuts down (as it should) then runs again after cooling off. Fortunately, I have used it more to cut down trees than I have to pull anyone out.
 
Cheers for the info, I'll definitely run the hand throttle at about 2k when winching from now on. My foot will be on the brake, trans in neutral anyway.

I might borrow a current clamp and verify what the winch is pulling, but it sounds like it will be fine with the stock 80A alternator. I think my bigger issue is a) poor grounding somewhere in the rig and b) the crank battery the car came with looks ancient and I'll probably get a nice quality one to replace it once it dies.

As for duty cycle, I dont have the manual in front of me but I seem to remember 60 seconds on, two minutes off being mentioned. The winch doesn't automatically cut out (it might if it gets hot though) and just relies on you to keep an eye on a watch.

Chang
 
Idle her up while winching and call it a day
 
I'm running the 80A stocker on dual 27 group and wired the winch to both batts - +to aux and -to crank.
SuperWinch10k
And hand throttle.
Haven't had to use the hand throttle for winching as the headroom across 2 batts provides pretty good run time. The longest time I've run the winch was pulling 4 rigs out of a ditch. Think I did 45/20sec on/off or something like that. Used a snatch block on all the pulls, so it was pretty easy going. Truck simply idled the whole time.

It's really about storing as much of the current an alternator creates when its spinning.
 
See thats an idea, running a second battery in parallel.

My auxilary battery is in the boot with a voltage controlled isolator under the hood... I don't believe its part of the circuit in the current arrangement when winching as that isolator should cut off the auxiliary battery if the crank battery side drops in voltage... this is by design so the alternator charges crank battery first then auxiliary. I wonder if I can make up a bypass switch for the isolator specifically for when im winching? 🤔
 
I wonder if I can make up a bypass switch for the isolator specifically for when im winching? 🤔
What is the thought here? To bypass the isolator and have the rear batt act as an aux with the crank?
You'd be dealing with a noticeable voltage drop from the rear batt in that arrangement (unless you're running 2/0 cable or some such). Not sure if it would cause issues somehow... maybe even damage to a batt or the winch?
Maybe not.
 
First the idle up, a definite advantage and as per above anything around 1500 - 2000 rpm is fine, when you see when someone is giving another persons car a jump start revving the arse off their motor they are a dumbarse, the typical alternator is 'all in' after 2000 ENGINE rpm, now think alternator pully size versus crank pulley size, your alternator is not doing 2000 rpm as in the same as your engine, with the smaller pulley it would be nearer 6000 rpm!

With that out of the way you need to check the battery specs. Starter batteries do not like to be 'pulled down' lower than around 75% of their capacity, they might work at the time but it does shorten their life. Forget full on leisure batteries as per above they are more long and slow drain., I use 2 x marine batteries which are a sort of compromise as I always take a fridge with me when out off road and when camping (diabetic so need to keep insulin cool) so they can be paralled via a Blue Seas VSR and if need be will cope with some winching if need be, so you need to check the cranking amps and the rate at which it/they can maintain it.

Next the winch, many winches use the equivalent of an engine starter motor, some actually use a starter motor (so only a 10 second/1 minute duty cycle), and even when they are geared they are working a lot harder than when starting your engine. Stated winch duty cycles are often well shall we say............'exaggerated'? It makes great marketing so I would keep that in mind.

So engine running around 2000 rpm.
Decent brand of battery/batteries.
Decent brand of winch and better than average cables.
Snatch block.

Something else to be kept in mind, if you uprate your alternator and cables and so forth, you will lessen the drain on your battery as the load will (even if not equal) be shared, and your battery/batteries will not only live longer but will come back up to around 85% charge quicker, after that alternators back off and will reduce their output to a few amps and it could take hours to bring the battery to a fully charge state, and I mean fully charged, a state a vehicle battery rarely reaches even when new.

Regards

Dave
 
All these reply's are actuate.
The battery starts your rig. The alternator runs your electrics and keeps the battery charged. Bumping the throttle to 2k RPMs puts the alternator output (as needed) close to full output (amps). As stated by Dave 2000, a starting battery does not take kindly to heavy discharge. Most winching is a 30sec pull. If more pulling is needed. Pause the pull as needed to let the battery recharge and the winch to cool down. The power cable from your alternator to the battery is what? 10 gauge 12 gauge at the most; good for an 80amp alternator. The 400amp max draw is based on how much line you have out (number of cable wraps) and the energy (amps) needed to get unstuck. You would know pretty quick if you reach max pull. If what your trying to move or pull does not budge. You stop the pull, re-evaluate, and reset as needed. Use a snatch block to double your pulling power as needed.

Some people add a 200-300amp breaker (resettable) on the winch line to protect the battery. The breaker trips to protect the battery/alternator. While this is a trick feature. Its not needed. People have been using the stock alternator/battery setup forever.

How old is your battery, are the connections in good shape? The size of your battery cables, the size of the winch cables all play a factor.
Normal battery life is 3 - 5 years. An old battery can shorten your alternator life because the alternator is trying to keep a failing battery charged. You can buy a starting/deep cycle battery if your worried. A starting/deep cycle battery also helps if your running lights/solar and only have the one battery.

If your cables are good with a sound battery. There should be no issues winching 30sec - 1 minute. Longer pulls just need to be managed.
 
Dave, Bubfuji, thanks so much for well thought out replies. Very informative.

I'll go over with a multimeter when I get home to confirm good chassis earth and operate the winch as above, healthy duty cycle and throttle at 2k.

The crank battery is old and tired, I'll look at getting a new one soon. A starter/deep cycle sounds good, but as with everything in life theres probably a compromise if the battery can function as both deep cycle and a starter?

Sounds like my stock alternator setup is perfectly fine. Cheers!
 
Dave, Bubfuji, thanks so much for well thought out replies. Very informative.

I'll go over with a multimeter when I get home to confirm good chassis earth and operate the winch as above, healthy duty cycle and throttle at 2k.

The crank battery is old and tired, I'll look at getting a new one soon. A starter/deep cycle sounds good, but as with everything in life theres probably a compromise if the battery can function as both deep cycle and a starter?

Sounds like my stock alternator setup is perfectly fine. Cheers!
You are right about having a start/deep cylce battery,they are a compromise however, if you go for a proper marine batteries the real quality is there, follow the correct winching procedures and it/they will last a long time. I change my marine batteries as a matter of course every four...ish years, to keep them healthy I also have a 150 amp alternator as well, if you intend to winch once a month then the stock alternator is fine, if you intend to be out every weekend then do the alternator upgrade, your battery will thank you for it.

Whenever my car is parked and the roof rack is on (10 months of the year) I have a solar panel fitted which sldies out from underneath, if the rack is off and the car is in the garage, then the roof rack on the garage roof is plugged into the rear bumper, in general my batteries are as close to full charge as they can be most of thier life, as an asides most marine batteries also tend to have two terminals for both positive and negative, this keeps auxilary wiring tidy.

Regards

Dave
 
Stock Alt with a Warn M10,000 winch forever. I have dual batteries, but not necessary if the main battery is of decent quality and capacity. Group 27F fits in the same space nicely and w/o any mods. Some have shoehorned a group 31 but had to reverse terminals and such.
 
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Unless you plan to winch for a living, the stock alt and a single battery along with raising the RPM to about 1500 works fine. Other than tow drivers or hardcore buggies, I've never seen a situation that warrants more than that. If you're draining the battery, you're not resting the winch enough.
 
The Runva winch I have has a peak draw of 400A
Wouldn't that be the starting in-rush current for the winch motor. Most winch solenoids are rated about 300-375A inrush and around 60 amp continuous while pulling I believe.
 

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