1 Wire Alternator

[jwebb]

Does the alternator need to be grounded or just the 1 wire running to the starter solenoid? Battery isn't charging, what else ??

[PeteH]

I do have a separate ground jumper on my 1 terminal alternator, but I cannot tell in the phone pics I have handy exactly how it connects. I seem to remember a small stud for a an eyelet type connector. Will have to look at home this evening. If you are using a remote starter solenoid, be sure that red charge wire is connected to the battery side and not the starter side. That wire has to be connected directly to the + battery cable somewhere otherwise the charge current won't get back to the battery.

[DaveS53]

http://www.tuffstuffperformance.com/files/pdf/1-wire_alternator_instructions.pdf

There's a you-tube video that says there may be a need to briefly touch a wire from the output terminal to the R terminal (if there is one) to excite the alternator, the first time.

https://www.youtube.com/watch?v=QPl7CTb685I

[Norm B]

I did not run a ground, just 1 heavy gauge wire, through a 100 amp fusible link, directly to the battery. My battery is front mounted like the Breeze forward battery box. Works great.

Norm

[NAZ]

Take a look at the attachment Dave posted. At ~170-degrees from the output terminal is a small raised pedestal. Most one-wire alternators have a threaded pedestal to use for a ground wire as they are case grounded. Using a ground wire from here directly to the block (assuming the engine is grounded like it should be) or to the chassis will provide a reliable ground source so you don't rely on the alternator mounting brackets for a ground. Yes the mounting bracket usually is good enough but I've seen some installations that have corroded bad enough I wouldn't rely on the mounting bracket to ground the charging system.

[Avalanche325]

1 wire alternators will typically not charge until the RPMs come up. They do not have an excitation circuit like a "regular" alternator. Even after being excited, they can drop out when the RPMs come down.

I am not a fan of them.

[CraigS]

1 wire alternators will typically not charge until the RPMs come up. They do not have an excitation circuit like a "regular" alternator. Even after being excited, they can drop out when the RPMs come down.

I am not a fan of them.
I probably would not have chosen a 1 wire but my car came w/ one. It's been 10 years. Once in a while I will notice that the alt isn't charging right after I start the car. If it's early in the AM I don't worry about it as it will start charging as soon as i pull out of the driveway. If it's not early, I give it a small rev to about 2000 and up pops the V meter.

[Itchief]

I agree with naz the alternator will need a proper ground to work

Rick

[CraigS]

While the alt may need a ground, I am trying to imagine how you bolt one to the head/block and not have a good ground.

[TexasAviator]

My 1 wire isn't grounded. The block is however.

[TexasAviator]

I probably would not have chosen a 1 wire but my car came w/ one. It's been 10 years. Once in a while I will notice that the alt isn't charging right after I start the car. If it's early in the AM I don't worry about it as it will start charging as soon as i pull out of the driveway. If it's not early, I give it a small rev to about 2000 and up pops the V meter.

Mine does this as well but it's also running at a lower rpm as most pulley systems are an underdrive to cause less parasitic drag.

[boat737]

Mine does this as well but it's also running at a lower rpm as most pulley systems are an underdrive to cause less parasitic drag.

How about Form Drag, or Surface Drag, or Friction Drag, or Induced Drag? (Sorry, just had to ....)

Seriously, my Alt pulley is overdriven. It looks to be spinning at least 2 or 3 times the crank RMP, maybe more. I haven't had any Exciter problems or issues, but it is still new.

My "One" wire goes from the Alt directly to the battery (through a circuit breaker). I bypassed the starter solenoid. Also, I do not have a dedicated Alt ground, but the block is grounded with a dedicated circuit wire.

[CraigS]

Boat I used to have one of those tiny pulleys on my alt also. Never payed it much attention until I was looking for a noise. It was not related at all to the noise but, once I saw the diameter and compared it to the crank pulley, I decided the alt didn't need to spin 3 times engine speed (my wild guess only). So I found a larger pulley. Maybe they put those tiny pulleys on the 1 wire alts on purpose but I didn't like the idea.

[boat737]

Boat I used to have one of those tiny pulleys on my alt also. Never payed it much attention until I was looking for a noise. It was not related at all to the noise but, once I saw the diameter and compared it to the crank pulley, I decided the alt didn't need to spin 3 times engine speed (my wild guess only). So I found a larger pulley. Maybe they put those tiny pulleys on the 1 wire alts on purpose but I didn't like the idea.

Thanks Craig. That's what came with the motor... I didn't even know there were options for that pulley, just assumed they were all standard and the same. Shows what I know... (or not know...)

[Just puttering]

With the car off - do you have 12 volts at the alt? What is the voltage when off? Then start the car and if need be rev it up then what is the voltage at the alt? The voltage will always be higher when running. Then check the voltage at the batt it should also be higher when running!