charging problem while winching

njedgexj

NAXJA Forum User
when i am using my m8000 my voltage will drop below 9 and my check guages comes on..even if i have my foot on the gas to ramp up the rpms..after 30 secs or so voltage will return to normal..then does it again, and again till im done winching..i have replaced 2 alternators with no effect..all my wiring has been upgraded under the hood..any ideas..could my winch be the cause of this..
 
ok question did you replace the alternators with other stock ones?
and what kind of battery are you using?

my guess would be when you winch is under a hard load it is trying to pull more than you current system has available and the strain is causing a voltage drop. you battery may be the weak point depending on what kind of alternator you are using.
 
when i am using my m8000 my voltage will drop below 9 and my check guages comes on..even if i have my foot on the gas to ramp up the rpms..after 30 secs or so voltage will return to normal..then does it again, and again till im done winching..i have replaced 2 alternators with no effect..all my wiring has been upgraded under the hood..any ideas..could my winch be the cause of this..

How hard does your winch seem to be pulling? How old is the winch? Chances are if it is old or hasn't been used much, there's rust built up on the inside of the drum, causing the brake to snag. If there's tension on that brake it'll make that winch work harder, thus drawing more power. Your brushes and armature in the motor and/or solenoid connections could be corroded/loose, too. Open the solenoid box and check the connections, clean up anything that is fuzzy, and check your grounds. Winches do weird things when they need servicing or aren't adequately hooked up. :) Also make sure BOTH positive and negative cables are hooked directly to the battery!
 
You need to raise the idle while you are winching, I stick a piece of rubber hose between the throttle stop and the throttle to raise the idle up to 1500-2k

Works for me any way
 
yes i replaced with stock ones..battery is a yellow top..the winch is under 3 yrs old..doesnt it gets used periodicly..does not seem like brake is sticking i will chech all connections and clean up anything that looks fuzzy..winch is directlly connected to batt..i know many ppl with the same or larger winch and they never had problems..i know the pcm controlls the alternator output wonder if thats not working right..after upgrading my wiring i did notice it starts up faster and all lights are brighter..but still same winch issue
 
just some food for thought but the volt gauge is not accurate. you might try a hand held volt meter and check your amprage draw and voltage at the battery when you are using the winch under heavy and just spooling and see what that tells you. you may beable to find your week spot. the battery might be getting old as well. i know my red top after hard use for a trailer winch and then in multiple vehicles before my jeep is starting to nolonger hold a charge. it is well beyond the three year warenty though.
 
You said you upgraded your wiring?

What size battery cables?

What size cable from alternator to PDC?

What is the rated amps of your alternator?

What is the cable size for the unibody ground?
 
I would upgrade the alternator to something that puts out a few more amps at idle. Then upgrade the wiring from battery/alternator/grounds - talk to "5-90" in the Sierra Chapter about making you some cables if you haven't upgraded them already. If yes, what wire size are you using?

Winching takes a TON of energy.
 
batt is less than a ys old..i def will check with a more accurate meter and see whats goin on..all cables are 0 guage welding wire.all ends are properly crimped and heat shrinked.i did notice an improvement from starting and when all my lights, radio,heat is on with the new cables.so they are working..alternator is 117 amp stock replacement..
 
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The 9000 draws a hell of a load on any one battery. IFthe batt is bad I would look into a 2 battery system. Only being a year old don't mean a thing. They come bad from the factory and heavy use a winch can eat them up to. When I plowed I could EASLY eat a battery up in a winter.
ALSO run a draw test on the winch If you can find someone that can handle that kind of amps. Super winches of today love to over heat and burn up. You just can't use them under full load like the 5000. If it gets very hot fast even under light load it;s a good sine she gone south. Then a bad wench will eat up a batt in no time.
 
Start testing - I'd look at the battery first even though it's a year old yellow top, try leaving it on a maintainer (the Optimas seem to respond well to a slow charger).

I have 3 Jeeps with M9000's, and stock alternators. The winches are used regularly. Long pulls under a heavy load are common. No problems.
 
A good alternator and a good battery should run the winch with no problems. With the wiring upgrades you've done, most likely you have a weak battery (even though it's only a year old) or a problem with the winch.

What brand winch? M8000 Warn?


It is normal for the voltage to drop on a long winch pull. The longer the pull the more the voltage will drop as the reserve is drawn out of the battery. I use a small size battery on the buggy and I have to be careful when winching to not pull the battery down too much. I over did it once on a very long hard pull (dead pulling a rig out of a canyon) and ruined an expensive battery with that one pull. The heat generated inside the battery is intense. Now I just stop more often on long pulls to let the battery rest and recharge.
 
I run a solar charger/maintainer, that has a diode in to to prevent overcharging. Only ran me about 35$. But, definitely load test the battery.. and possibly go the route of higher output alt, maybe second battery.
 
I have an M8000 on Katy's rig and it has the same problem. I just take breaks to let the charge catch up. It's done it with multiple batteries, and never had a problem charging otherwise. I had always assumed that it was just that Hard pulls draw lots of amps.
 
I have an M8000 on Katy's rig and it has the same problem. I just take breaks to let the charge catch up. It's done it with multiple batteries, and never had a problem charging otherwise. I had always assumed that it was just that Hard pulls draw lots of amps.


Yep, he may have no problem with his battery or charging system. A higher output alternatior is always nice, but they will put out less amps at idle. Also, when the winch is drawing 250-350 amps (or more), it doesn't matter that much if the alternator puts out 100 or 130 amps, it's still using the battery for reserve. You just have to take breaks on long hard pulls.
 
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