How to improve the winch performance? (1 Viewer)

[CharlieCR]

Hi, I have an Fj40 1974, it has a 15500 lb Smittybilt winch, stock 40 amp alternator an a yellow top optima battery. I would like to keep the current set up (1 battery). I would like to upgrade the alternator but I´m not sure which type would fit properly. A friend told me that a good choice would be to change it for an alternator with higher amps (voltage regulator included), and that it would not only improve the winch performance but the power of the car (I have a DUI distributor installed).

I don`t winch very often, nevertheless, the last time I did a hard pull, I think it took around 30 min to drain the battery (winch and battery were brand new), even thought I was giving it the time to cool down to "recharge"; at the end, I was pulled out by two winchers ...

Cheers!

 

[96bruizer]

Probably an obvious question, but do you increase the rpm’s as your winching?

 

[CharlieCR]

Probably an obvious question, but do you increase the rpm’s as your winching?

Thanks for asking, yes I did, I have a Holley carburetor so I pull the choke while not pressing the gas.

 

[Living in the Past]

If you look at the amps your electric winch is drawing you will see why dual battery setup is really the way to go. It would take quite a alternator to keep up with a electric winch. You really need stored power for a continuous pull. Just upgrading your battery to the highest cold staring amp would probably be as big a help as a larger alternator. I would be sure you factory wiring is protected as well. Not sure your current amp meter would like a alternator putting out a lot more amperage than it's rated for. Not sure about the voltage regulator either. In 1974 the FJ40 was setup to run a PTO winch not a electric winch. Want to be sure any modifications to the electric system doesn't harm the forty five year plus wiring and gauges.

 

[73FJ40]

@CharlieCR

Optima says the largest yellow top they manufacture are their Group 31 batteries, which are 75 amp-hour batteries with a reserve capacity of 155 minutes.

Divide 75 plus your alternator output (40 amps) by the motor amps above and that will tell you how many fractions of an hour your battery may last. 75 plus lets assume your full 40 amp alternator = 115. divided by assume 240 amps (6000 lb line pull) = 0.48 hour or about 29 minutes. This assumes a first layer pull. Higher draw on more layers.

If you go to a high output alternator, it will need a pretty wide serpentine belt to deliver the power to the alternator.

 

[thebigredrocker]

Here's a slick way to add a passenger side battery. 4PlusProducts | FJ40 | Accessories | Battery Trays

 

[White Stripe]

I increased the size of my single battery to a group 31. Then I converted to a gm 1 wire alternator and converted the amp gauge to a volt gauge. Right now I am using a 90 amp alternator but can swap in a 180 amp I believe.

 

[peesalot]

good wires and connections will do wonders on the winch.

 

[73FJ40]

According to the optima battery website, you need a deep cycle battery for this application. The best battery to provide the most amps would be one with the most amp hours.

CCA are important for cold start climates, but typically they are not deep cycle batteries.

 

[1911]

If you go to a high output alternator, it will need a pretty wide serpentine belt to deliver the power to the alternator.

I increased the size of my single battery to a group 31. Then I converted to a gm 1 wire alternator and converted the amp gauge to a volt gauge. Right now I am using a 90 amp alternator but can swap in a 180 amp I believe.

I am running a Mean Green alternator in mine, which is just a souped-up GM CS-130 I believe. But it is capable of 200 amps, and runs on the stock pulleys and belt width just fine. I did replace my ammeter with a voltmeter, so as not to blow the ammeter up.

https://www.mean-green.com/1975-1987-LANDCRUISER-42L-MG14573.htm

I have done some really heavy pulls with this alternator and my Warn 8274 winch, but none that required anything like 30 minutes or more of winching.

 

[CharlieCR]

@CharlieCR


View attachment 2327540

Optima says the largest yellow top they manufacture are their Group 31 batteries, which are 75 amp-hour batteries with a reserve capacity of 155 minutes.

Divide 75 plus your alternator output (40 amps) by the motor amps above and that will tell you how many fractions of an hour your battery may last. 75 plus lets assume your full 40 amp alternator = 115. divided by assume 240 amps (6000 lb line pull) = 0.48 hour or about 29 minutes. This assumes a first layer pull. Higher draw on more layers.

If you go to a high output alternator, it will need a pretty wide serpentine belt to deliver the power to the alternator.

Thanks for your information.!

 

[Braden620]

PTO.

 

[73FJ40]

@CharlieCR

The chart I posted indicates you'll likely need a "high output" alternator, e.g., at least 240 amps.

According to the mechman.com/faq, a high-performance alternator supplier:

"Single V belt and 4 rib serpentine belts will start to slip at about 150 amps worth of load. For minimal belt slip, 240 – 370 amp alternators should not be driven by anything narrower than a 6 rib serpentine or dual-V belt drive setup."