Alternator Smaller Pulley (1 Viewer)

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sawtooth4x4

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Does anyone know of another pulley for the alternator that fits, that has a smaller diameter so it’ll turn faster?

Only asking because I upgraded to a sequoia alternator and it’s only making 12.5 to 13.1 Volta at my normal driving speeds. I noticed when I rev the engine up to around 4K I’m making 13.7volts.

Thanks
 
If you are not getting proper voltage at lower RPM, 1200 to 1500 RPM then there is some other problem and changing the pulley is not going to solve your problem. First thing I would have the alternator tested
 
Smaller pully won’t get you more power during Normal use. Take off and Clean your battery terminals, and have your alternator tested
 
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If you’re trying to get a higher output at idle - say for running a which or something - get an OEM hand throttle cable so you can set the rpm manually. Plug and play. Otherwise, consider a 150A Sequoia alternator upgrade.
 
I have a brand new sequoia 150 alternator. It’s been tested and works fine.

brand new battery.

brand new battery cables and terminals.

I’m looking for a smaller pulley to get it turning faster for normal driving and idling.
 
sawtooth4x4 said:
I have a brand new sequoia 150 alternator. It’s been tested and works fine.

brand new battery.

brand new battery cables and terminals.

I’m looking for a smaller pulley to get it turning faster for normal driving and idling.
Click to expand...
Photoman kit? Doesn’t he have a smaller pulley in the kit?
 
sawtooth4x4 said:
I think that’s the bracket I bought.

it’s been a couple of months. I just got a harness and bracket. Didn’t know about the pulley too.
Click to expand...
What pulley did you use then? Didn’t your sequoia alt have a serpentine pulley on it??
 
You can swap the original 1FZFE alternator pulley right over to the sequoia alternator. Takes about a minute with impact tools.
 
I'll have to do a little more research, but I think one of those is the ticket. I just need to measure the stock pulley. If I can fit my hand in there again.
 
sawtooth4x4 said:
Does anyone know of another pulley for the alternator that fits, that has a smaller diameter so it’ll turn faster?

Only asking because I upgraded to a sequoia alternator and it’s only making 12.5 to 13.1 Volta at my normal driving speeds. I noticed when I rev the engine up to around 4K I’m making 13.7volts.

Thanks
Click to expand...
How and where are you measuring voltage?
You should be seeing proper voltage at idle across the battery terminals after start up. Approx 14.4 VDC.
If the output of the alternator is actually low, then something is dragging the output down (shorted cell in battery) or the voltage regulator in the alternator is faulty.

Another possibility is a huge parasitic load when running. You should be checking voltage with all accessories off.

As previously stated, a smaller pulley is not what you're looking for to solve this issue.
 
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I’m using my scanguage2 which gives me a voltage reading while driving.

admittedly I’m not a Toyota guy. I’m a Land Rover guy and a Ram Cummins guy. All my alternators usually run around 14V. But they have stock alternators

this truck has always sat a tick above on the positive voltage gauge on the dash. Even with a stock alternator.

I’ve replaced all the battery cables and connections. A new battery.

The voltage does go up to the correct place if it revs to 3k.

The battery and alternator are brand new. Not even a month old. Both were tested before install. Both passed the test.
 
sawtooth4x4 said:
I’m using my scanguage2 which gives me a voltage reading while driving.

admittedly I’m not a Toyota guy. I’m a Land Rover guy and a Ram Cummins guy. All my alternators usually run around 14V. But they have stock alternators

this truck has always sat a tick above on the positive voltage gauge on the dash. Even with a stock alternator.

I’ve replaced all the battery cables and connections. A new battery.

The voltage does go up to the correct place if it revs to 3k.

The battery and alternator are brand new. Not even a month old. Both were tested before install. Both passed the test.
Click to expand...
When troubleshooting these types of issues, voltage readings should always be checked across the battery terminals first.
My first check would be across the battery terminals with the engine off after sitting overnight. This will give you a general status of the battery's state of charge. Depending on the type of battery (flooded/AGM/etc) a full charge will read in the neighborhood of 12.6 or 12.7.
Then start the engine and again measuring across the battery terminals, you're looking for 14.4 depending on the state of charge of the battery. A FULLY charged battery will read lower voltage with the engine running as the alternator senses state of charge.

After that, you can check the actual voltage on the rear stud of the alternator and make a comparison between the 2 readings. A significant difference indicates a voltage drop between the alternator and the battery.

Another thing to consider is that the OEM alternator is rated at 80 amps. The cabling between the alternator and the fusible link is also sized for that current. If you're almost doubling the current output of the OEM alternator, the wiring needs to be upgraded as well. Your fusible link FL AM1 is rated at 80 amps. That is what feeds the battery from the alternator. It also needs to be upgraded.
 
I know that you said your alternator test good, but it sounds marginal to me. I say this because I got a Sequoia alternator from junk yard. It had the same behavior. It tested good on the Napa machine. However, I know someone that runs an automotive electric shop and had him rebuild it anyhow. Works like a champ now. I do have the small pulley, but that just gets it to light up at lower RPMs. The regular pulley should still allow it to produce full output and normal RPMs.
 
I second @jonheld and @Cruzerman

There is an issue, what you are experiencing is not something you should see during normal operation. Just putting a smaller pulley on it will not fix the issue if it does anything at all.
 
I have gone down to have the alternator tested at Oreillys. The alternator is going out and almost dead.

this is my 3rd alternator now that has died on this thing. 1 from Amazon 2 from Oreillys.
 
sawtooth4x4 said:
I have gone down to have the alternator tested at Oreillys. The alternator is going out and almost dead.

this is my 3rd alternator now that has died on this thing. 1 from Amazon 2 from Oreillys.
Click to expand...
Denso alternator from Rock Auto or direct to Toyota?
 
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I put a new alternator in. Drove it all day Saturday and I finally get 14v all the time on my scangauge2. Thanks for convincing to get it replaced. The only good thing is the lifetime warranty at OReilly.

and now I can get the alternator swapped in about an hour.
 
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