Not Charging Battery

gofast

Active Member
My LSJ just turned on the red battery light on the dash, and the alternator is making a squealing noise.
The used-auto-parts-yard have $27 alternators for the normal Cobalt, but don't have my SC LSJ engine's alternator.
Looking at the form factor, the two alternators look the same, physically, but the LSJ one has a different electrical plug.
I am tempted to buy the basic alternator, and the normal Cobalt electrical plug, and solder it into my engine harness... I really don't need the rare 135A alternator. Will this work? I don't have the connector/electrical view for the normal Cobalt alternator.
Oh yeah, I need to keep the 6 rib pulley off the old alternator, as the basic one is a 5 rib pulley.
Thoughts?
View attachment 18023

View attachment 18025
 

gofast

Active Member
I purchased a rebuild kit for my 2009 SS off Ebay for $49. Everything you need is included. Soldering the slip ring is a challenge but replacing the rest of the parts is easy. I had one brush, the slip ring and one bearing either failed or just ready to fail.
 

Ross

Goblin Guru
Has anyone replaced the alternator pulley on a LSJ?
The 6 rib pulley on my LSJ alternator is worn out, and now free spins without moving the armature.
The stock pulley is an overrunning / decoupler pulley that normally free spins clockwise, but engages the alternator when spun CCW.
This reduces belt shock and bouncing when the engine drops RPM.
18649


I ordered a new CONTINENTAL 49912 pulley, which is suppose to fit my 06 LSJ, but it didn't match the main thread.
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My LSJ alternator shaft starts as 17mm shaft, then tapers down to a left hand M14x1.5 thread.
The new pulley has same dimensions except the main thread is a LH M17 thread.
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Rock auto has other pulleys for my LSJ, but they don't mention the main thread in their specs. Not sure if my alternator shaft is unique, or if the suppliers have the threads wrong.
 

ctuinstra

Goblin Guru
I know my question won't help but when others are saying that you run the alternator backwards, is that on the base or turbo models? If you have left hand threads, in theory, they shouldn't be run backwards otherwise it could unscrew the pulley.
 

Tinkles

Well-Known Member
I know my question won't help but when others are saying that you run the alternator backwards, is that on the base or turbo models? If you have left hand threads, in theory, they shouldn't be run backwards otherwise it could unscrew the pulley.
When installing a supercharger on a non supercharged Ecotec you will spin the stock alternator backwards and it will still charge. However unscrewing the alternator pulley isn't a concern that I have seen happen in my 10 years of owning a supercharged Ecotec Cavalier or in my 13 year history with the Cavalier/Sunfire community. Installing the LSJ supercharger kit is the most common way of boosting an ecotec Cavalier or Sunfire so I am very confident that it isn't an issue to worry about. The only real reason someone(including myself) would swap to the LSJ alternator would be to gain the 6 rib pulley because all others are 5 rib and require to cut a rib off the belt.
 

Ross

Goblin Guru
I know my question won't help but when others are saying that you run the alternator backwards, is that on the base or turbo models? If you have left hand threads, in theory, they shouldn't be run backwards otherwise it could unscrew the pulley.
The supercharged LSJ runs the alternator counter clockwise, and that is why the stock alternator has left hand threads.
I believe the NA and turbo engines run the alternator clockwise, and have normal threads.

When installing a supercharger on a non supercharged Ecotec you will spin the stock alternator backwards and it will still charge. However unscrewing the alternator pulley isn't a concern that I have seen happen in my 10 years of owning a supercharged Ecotec Cavalier or in my 13 year history with the Cavalier/Sunfire community. Installing the LSJ supercharger kit is the most common way of boosting an ecotec Cavalier or Sunfire so I am very confident that it isn't an issue to worry about. The only real reason someone(including myself) would swap to the LSJ alternator would be to gain the 6 rib pulley because all others are 5 rib and require to cut a rib off the belt.
The LSJ alternator won't work if you run the pulley clockwise. It won't engage the armature. That is what a CCW overrunning pulley does.
 

Tinkles

Well-Known Member
The LSJ alternator won't work if you run the pulley clockwise. It won't engage the armature. That is what a CCW overrunning pulley does.
That is correct. But to answer Ctuinstra's question, it is the non supercharged engines(2.2L, 2.4L or even the 2.0L turbo engines) that will spin their stock alternators backwards when you install the supercharger kit onto them. The LSJ is the odd man out in reference to what direction the alternator spins because of the belt routing do to the supercharger and is the only one with the special pulley.
 

Lonny

Administrator
Staff member
When we installed a supercharger on Adams first Goblin we used a single sided belt and it kept the alternator spinning clockwise.
The SS supercharged factory setup used a double sided belt that uses the back of the belt to drive the alternator which causes the alternator to spin backwards.
 

Ross

Goblin Guru
The supercharger add-on kits run the alternator with a standard pulley?
I wonder if my LSJ will work fine if I modify the overrun pulley to become a standard direct drive pulley.
The clutch is worn out of the pulley, and I can't seem to find a supplier for my overrun pulley.
 

Ross

Goblin Guru
Well I turned my alternator overrun pulley into a regular pulley by making a rubber washer out of an old inner tube, then tightening on the left hand threaded outer nut with the 19mm allen head.
18831

Mickey mouse? MacGyver fix? Well, the alternator is working now.
Took it out for a test run yesterday, and discovered that I hadn't torqued the allen nut enough, and when I shifted into 2nd gear, it unthreaded.
Used the impact gun this time, and need to cut the rubber back a bit.

Update: Well that didn't work too well. The pulley unthreaded when I got off the throttle. I will try a Gates override pulley and hope that their pulley works better than the Continental pulley, which didn't fit.
 
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JBINTX

Goblin Guru
Well I turned my alternator overrun pulley into a regular pulley by making a rubber washer out of an old inner tube, then tightening on the left hand threaded outer nut with the 19mm allen head.
View attachment 18831
Mickey mouse? MacGyver fix? Well, the alternator is working now.
Took it out for a test run yesterday, and discovered that I hadn't torqued the allen nut enough, and when I shifted into 2nd gear, it unthreaded.
Used the impact gun this time, and need to cut the rubber back a bit.
only way the story would have been better is if the rubber innertube had come from the donor car........ ;)
 

Ross

Goblin Guru
The Gates alternator pulley has the M14x1.5 left hand thread that my LSJ alternator has!
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So the proper fix is now installed. It was $85 for just the pulley! For $20 more I could have bought a rebuilt one... just didn't trust it would be as good of quality as my current alternator. My mickey mouse rubber tube fix didn't last very long, and it unthreaded.
 
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