Outer Limits 4x4 Board

Hey crew,

I have a ? for you's

Alternators, i run spotlights(24mill candle power) at times on my car. i have had issues in the past where the battery gets drained after several hours of driving around at 30kph spotlighting at night.

What i was thinking was getting a bigger alternator, am i correct in the following

1. Getting a bigger alternator will need to turn faster to charge more, therefor you would need a bigger pulley(if thats what u call it)
2. doing this will make the fan slower, therefore could cause heating problems
3. sitting at 1000 rpm will the alternator even charge enough?

a bigger pulley will spin the alternator slower than a smaller one.

Different alternators have different charge rates and a bigger alternator won't necessarily put out more power than a small one.

If you want to get a higher output one go and see your local auto elec. He will know (or should know) what will work best. More often than not some of the late model Jap imports that have power everything have high out put alternators that are quite compact.

what size is ur battery? if ur battery is to small you will loose charge real quick, i would advise a bigger battery for starters , a deep cycle would be better, also if ur alternator is not charging between 13.5 and 14.5 volts you have a problem..

i just had my alternator rewound for better output. Went from a 55 to about 120. Cost me about $150 but was easier than having to try and fit a custom application and have to worry about brackets and belts etc

Also ensure your wiring is 100%, all connections are clean, your battery needs to be in top condition so make sure it has the right amount of water, terminals are clean, battery clamps are clean and attached properly

hey grimbo,

Who did your alternator?

i have had Duncans in sth melb do one and City Auto electrics on Elizabeth St in the city do one as well. Both times roughly the same price. One was a Sierra alternator years ago and the other was to the Corolla one

If ya search there is a few threads on this, i think that there was mention of a mazda alternator that straight fit with like 100amp output, cant remember exactly what , think it of a KL engine.
Layto....

For a while i ran an extra alternator on the passenger side of the motor
i ran a second battery as well the thing was only wired to my winch and rock lights so they where on a seperate circiut all together ,I had an isolation switch that could be flicked to jion both circiuts, in case of one system failing ,and my spelling is getting worse .

bazooked wrote:i would advise a bigger battery for starters , a deep cycle would be better

Deep Cycle?????
Do you actually know what a deep cycle battery is designed for???

certainly not for cranking a motor over! (unless in an emergency situation)

Deep cycle batteries are designed to run completely flat and be recharged quickly - for accessory items such as a fridge or lighting at the campsite.
As well as being the incorrect battery for the intended purpose the warranty on a deep cycle battery is 1/2 the length of the equivalent cranking battery - generally a deep cycle battery has only 12 months warranty.

And what about put dual batteries isolated and run the spotties from the deep cycle leaving the crancking one just for start the engine and for the original circuits???

I have a large 880cca battery as my starting battery and all the standard items. I then have a second 600cca battery for my lights, radio, extra power point etc. The two batteries are isolated from each other so I should theroretically be able to start all the time

i run a deep cycle battery in my zook never had a problem, its 1 0f those exide orbital batteries, it runs evrything including all the lights winch and fridge when i go away all on 1 battery and a standard zook alternator...

I have a 2month old exide 550, biggest one i could get that would fit in the standard battery tray.
It has a light that displays if its charged or close to empty... after a few hours spotlighting it goes black(<50% full)

I want to get dual batteries but want to make sure the alternator will handle it, no point having a 35amp alt with 2 batteries and my 2nd battery not having enough juice to keep me going.

I think swift/barina alternators are higher output, but not all fit because some have multi v belts, christover

you can go to www.roadlessgear.com, and look at the GM alternator bracket. you can put a chevy alternator on your samurai (is that what you have?) and i think it almost doubles the output. this is without changing the pulleys or anything. this is what a lot of folks do here in the states. i have a friend that runs a winch, some 100w PIAA offroad lights, and PIAA headlights, as well as his sound system and doesnt have any problems any more.
joe

"I know the alternator from a Mazda KL engine will bolt straight to a G13. Puts out around 100amp"

So now i got the option of either getting a alternator, or rewinding my own(the auto sparkie said it will go about 80-100amps)

it'll cost between 160-200 for the rewind and take 2 days

KL engine alternator is $110 from the wreckers

Now i'm torn between just getting mine rewound or getting a KL alternator. what would u guys do?

Hmm, off the road for 2 days, or pick up from wreckers and fit in an afternoon, id get the KL, if the pulley is correct.

yeah thats what i was thinking, cheaper and probably a lot quicker

have to have a look at the pulley tho cos i dont wanna get it and then find that it does not fit or is the wrong size