How do you clock a alernator?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Very simple proceedure if you have a impact gun.
1, impact the pulley and fan off,
2, remove the bolts holding both cases together,
3, hold the rotor down pulling the front case up a inch or so,
4, rotate the case to whaterver position you want,
5, push the cases back together and replace the bolts,
6, replace the fan and pulley with a impact,
Done, now wasn`t that simple? ...
Should not take over 5 minutes on a fresh unit. A used alt requires a little more time as the rotor or cases may be stuck....
PS, do {NOT} seperate the rear case and rotor, if you do the brushes will pop out. And that is not necessary to merely re-clock a alternator.
1, impact the pulley and fan off,
2, remove the bolts holding both cases together,
3, hold the rotor down pulling the front case up a inch or so,
4, rotate the case to whaterver position you want,
5, push the cases back together and replace the bolts,
6, replace the fan and pulley with a impact,
Done, now wasn`t that simple? ...
Should not take over 5 minutes on a fresh unit. A used alt requires a little more time as the rotor or cases may be stuck....
PS, do {NOT} seperate the rear case and rotor, if you do the brushes will pop out. And that is not necessary to merely re-clock a alternator.
EASY
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Alternator, Trials and Tribulations.
I would think most of the CF members has never even seen the insides of a alternator let alone know how to pin the brushes. When you remove the back case without removing the fan and pulley from the front the springs holding the brushes will pop out as soon as you separate the cases and cause the person more grief and frustration trying to figure out what the hell has just happened. 
His 3 minutes may turn into hours and maybe days. Plus he just might want to come looking for you...
Remember if they knew how to do it, they wouldn`t have asked.
Safety Car
Joined: Jun 2004
Posts: 4,367
Likes: 221
From: Beecher Illinois
Maybe this will help. Note the pin holding the brushes into the holder(that small hole in the top of the holder). Inserted through the back of the case.
I learned this years ago when I didn't understand the workings of an alternator myself. Besides, it's nice to know how to replace the brushes just in case.
I learned this years ago when I didn't understand the workings of an alternator myself. Besides, it's nice to know how to replace the brushes just in case.
Last edited by KapsSA; Apr 26, 2007 at 01:54 PM.
Intermediate
Joined: Apr 2007
Posts: 33
Likes: 0
From: Confusion
Very simple proceedure if you have a impact gun.
1, impact the pulley and fan off,
2, remove the bolts holding both cases together,
3, hold the rotor down pulling the front case up a inch or so,
4, rotate the case to whaterver position you want,
5, push the cases back together and replace the bolts,
6, replace the fan and pulley with a impact,
Done, now wasn`t that simple? ...
Should not take over 5 minutes on a fresh unit. A used alt requires a little more time as the rotor or cases may be stuck....
PS, do {NOT} seperate the rear case and rotor, if you do the brushes will pop out. And that is not necessary to merely re-clock a alternator.
1, impact the pulley and fan off,
2, remove the bolts holding both cases together,
3, hold the rotor down pulling the front case up a inch or so,
4, rotate the case to whaterver position you want,
5, push the cases back together and replace the bolts,
6, replace the fan and pulley with a impact,
Done, now wasn`t that simple? ...
Should not take over 5 minutes on a fresh unit. A used alt requires a little more time as the rotor or cases may be stuck....
PS, do {NOT} seperate the rear case and rotor, if you do the brushes will pop out. And that is not necessary to merely re-clock a alternator.
Thank you sir! Great info!!!
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
Melting Slicks
Joined: Nov 2003
Posts: 2,668
Likes: 119
From: St. Charles Mo
CI 5 & 8 Veteran
That is my preference 
This method works too if you know what your doing. I would think most of the CF members has never even seen the insides of a alternator let alone know how to pin the brushes. When you remove the back case without removing the fan and pulley from the front the springs holding the brushes will pop out as soon as you separate the cases and cause the person more grief and frustration trying to figure out what the hell has just happened. His 3 minutes may turn into hours and maybe days. Plus he just might want to come looking for you...
Remember if they knew how to do it, they wouldn`t have asked.
I would think most of the CF members has never even seen the insides of a alternator let alone know how to pin the brushes. When you remove the back case without removing the fan and pulley from the front the springs holding the brushes will pop out as soon as you separate the cases and cause the person more grief and frustration trying to figure out what the hell has just happened. His 3 minutes may turn into hours and maybe days. Plus he just might want to come looking for you...Remember if they knew how to do it, they wouldn`t have asked.
Either way, it's always good to know what your doing. We all learn....sometimes the hard way
Bullshark
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Michael S. Palmer
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Opening the alt can be an easy option, and yes, an alternator can be re-clocked. It may be easy and it may be hard depending on a lot of factors.
Or...
Just take it back to the store, exchange it for an alternator that has the correct configuration. It's fast and easy.
I say this because I opened and worked on quite a few CS130s when I was swapping cases for chrome cases.
I found two different versions of CS130s, a total of three different rear case and gut configurations, and two rear cases that had two different clockings.
I also found out that if one of the four bolts it tightened even just a little more than any of the other three, the shaft binds in the bearings and won't spin right. If it gets installed in that kind of state it'll cause all kinds of problems.
Long story short, yes it's possible, but why go to the trouble if you don't have to. Exchange it for a correctly clocked alt.
Or...
Just take it back to the store, exchange it for an alternator that has the correct configuration. It's fast and easy.
I say this because I opened and worked on quite a few CS130s when I was swapping cases for chrome cases.
I found two different versions of CS130s, a total of three different rear case and gut configurations, and two rear cases that had two different clockings.
I also found out that if one of the four bolts it tightened even just a little more than any of the other three, the shaft binds in the bearings and won't spin right. If it gets installed in that kind of state it'll cause all kinds of problems.
Long story short, yes it's possible, but why go to the trouble if you don't have to. Exchange it for a correctly clocked alt.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Opening the alt can be an easy option, and yes, an alternator can be re-clocked. It may be easy and it may be hard depending on a lot of factors.
Or...
Just take it back to the store, exchange it for an alternator that has the correct configuration. It's fast and easy.
I say this because I opened and worked on quite a few CS130s when I was swapping cases for chrome cases.
I found two different versions of CS130s, a total of three different rear case and gut configurations, and two rear cases that had two different clockings.
I also found out that if one of the four bolts it tightened even just a little more than any of the other three, the shaft binds in the bearings and won't spin right. If it gets installed in that kind of state it'll cause all kinds of problems.
Long story short, yes it's possible, but why go to the trouble if you don't have to. Exchange it for a correctly clocked alt.
Or...
Just take it back to the store, exchange it for an alternator that has the correct configuration. It's fast and easy.
I say this because I opened and worked on quite a few CS130s when I was swapping cases for chrome cases.
I found two different versions of CS130s, a total of three different rear case and gut configurations, and two rear cases that had two different clockings.
I also found out that if one of the four bolts it tightened even just a little more than any of the other three, the shaft binds in the bearings and won't spin right. If it gets installed in that kind of state it'll cause all kinds of problems.
Long story short, yes it's possible, but why go to the trouble if you don't have to. Exchange it for a correctly clocked alt.
2)I cannot BELIEVE this is still going on.
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Hmmm... It takes 3 minutes to clock an alternator. Hard to believe that it would be "fast and easy" to "just take it back to the store, exchange it for an alternator that has the correct configuration."
I've done them myself many times with NO issues. What a crock of
I've done them myself many times with NO issues. What a crock of
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Out of all the alternators you have ever bought and installed...how many have failed? Ever wonder why they do that?
It took me about fifteen minutes each, to completely change a CS130 alt to a chrome case. You're very right that it can take 3 minutes. But that's you, and that's me, and a lot of these guys. But there are also a lot of guys here who may not be quite as fast at this, and maybe that first time ends up bad. Then he replaces the one that got messed up.
If it were me, I would try. If it were you, you would try. I've also spent hundreds over the years in car parts that I thought I could modify correctly on the first shot. Screw ups get expensive.
That's why I say to someone who has never worked on an alt, replace the new one with another new one, and practice on the old ones.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Out of all the alternators you have ever bought and installed...how many have failed? Ever wonder why they do that?
It took me about fifteen minutes each, to completely change a CS130 alt to a chrome case. You're very right that it can take 3 minutes. But that's you, and that's me, and a lot of these guys. But there are also a lot of guys here who may not be quite as fast at this, and maybe that first time ends up bad. Then he replaces the one that got messed up.
If it were me, I would try. If it were you, you would try. I've also spent hundreds over the years in car parts that I thought I could modify correctly on the first shot. Screw ups get expensive.
That's why I say to someone who has never worked on an alt, replace the new one with another new one, and practice on the old ones.
It took me about fifteen minutes each, to completely change a CS130 alt to a chrome case. You're very right that it can take 3 minutes. But that's you, and that's me, and a lot of these guys. But there are also a lot of guys here who may not be quite as fast at this, and maybe that first time ends up bad. Then he replaces the one that got messed up.
If it were me, I would try. If it were you, you would try. I've also spent hundreds over the years in car parts that I thought I could modify correctly on the first shot. Screw ups get expensive.
That's why I say to someone who has never worked on an alt, replace the new one with another new one, and practice on the old ones.
Can an alternator be clocked? Yes, it can. It's EASY.
After Wally posted the first REAL answer, it's done.
NOW, you say take it to the store.
They will just take it in the back, and do what Wally said.
If he wanted to take it back to the store, he would have posted "What is O Rielys return policy."
I am sorry DB, but I find your last post a giant backpeddling that serves no purpose. LET IT GO>
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
It took me about fifteen minutes each, to completely change a CS130 alt to a chrome case. You're very right that it can take 3 minutes. But that's you, and that's me, and a lot of these guys. But there are also a lot of guys here who may not be quite as fast at this, and maybe that first time ends up bad. Then he replaces the one that got messed up..
He was asking how to clock it not install a chrome case.If it were me, I would try. If it were you, you would try. I've also spent hundreds over the years in car parts that I thought I could modify correctly on the first shot. Screw ups get expensive.
That's why I say to someone who has never worked on an alt, replace the new one with another new one, and practice on the old ones.
That's why I say to someone who has never worked on an alt, replace the new one with another new one, and practice on the old ones.
This forum is to help answer peoples questions and do it themselves not rustle up business for car parts stores.As Mark Twain said, "It is better to keep your mouth shut and appear stupid than open it and remove all doubt."
Since I'm sure you will PMing a mod to let them know we are picking on you again.
IBTL
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
NEVER had any problems.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Exactly right. When I was younger, I worked at a few auto parts stores. If we had someone bring an alternator back in because the bolt position was off, we would simply use the impact wrench to remove the pully and rotate ("clock") the case. BTW, we didn't do it in the back, it was right there at the counter.
NEVER had any problems.
NEVER had any problems.
I didn't mean to have them fix the previously purchased version. I meant exchange it for a completely different alternator, one that already has the correct clocking.
