Underdrive pulley alternator issues
Thread Starter
Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
Underdrive pulley alternator issues I have a SLP 25% underdrive pulley ( P/N: 100226 )and the GM dealership states that the alternator is not putting out enough charge. Has anyone else run into charging problems with underdrive pulleys? Thanks!
I had some problems when I went to an aftermarket 160 amp alternator with charging, but never had a single problem with the OEM alternator (except for it crapping out on me - attributable to a leaking power steering pump). Even with an underdrive pulley, it should still idle at 800 RPMs all day long on a 6-speed car with no issues at all. I even have a moderate stereo in my car.
Originally Posted by Gregory
I have a SLP 25% underdrive pulley ( P/N: 100226 )and the GM dealership states that the alternator is not putting out enough charge. Has anyone else run into charging problems with underdrive pulleys? Thanks!
i was running 1350 watts of amplifiers on my slp pulley and only ever had any issues with the stereo cranked up sitting at a light,voltage would drop to 11 or 12, other than that no problems at all
Thread Starter
Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
Kind of funny . . . as the dealership didn't take my suggestion of a new starter. So, after waiting a week for the dealership to get a new alternator from Michigan I went to start up the car and it did the same thing. They called me and said it was ready, but it didn't start on their lot. Rapid click, click, click noises coming from the starter. They even tried jumping it to no avail.
I was kind of insulted as the service manager said I had lots of things giving the electrical system a load. When I asked him what specifically he was talking about he didn't say a word. I told him all I have added is a Meziere electric water pump. I have a factory stereo, no extra lights, not even a radar detector.
Is this an example of why GM is losing market share?
I was kind of insulted as the service manager said I had lots of things giving the electrical system a load. When I asked him what specifically he was talking about he didn't say a word. I told him all I have added is a Meziere electric water pump. I have a factory stereo, no extra lights, not even a radar detector.
Is this an example of why GM is losing market share?
Last edited by Gregory; Jul 25, 2007 at 11:21 PM.
What non-factory electrical load would be there when the key was in the start position?? 
Greg: If the voltage is a little low then just slightly increase your idle speed. Uping mine a mear 100 RPM pulled my voltage way up when idling at a stand still.
Greg: If the voltage is a little low then just slightly increase your idle speed. Uping mine a mear 100 RPM pulled my voltage way up when idling at a stand still.
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Thread Starter
Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
Six Speed: I agree with your premise of no electrical load from a start. Once I get my laptop back from Iraq I'll use the HP Tuner software to make the adjustment to the idle speed. Right now idle it is about 850.
I got the car back from the dealership yesterday. It would not start after driving about four miles. Click, click, click went the starter. Then, I left the car to cool about ten minutes and it started up. The dealership replaced the alternator and starter. Still, I wonder if heat is somehow affecting the starter. It's strange, because this is a new problem with the car after it sat during my deployment.
Still, I would like to know more about the oversize alternator pulleys. Jegs.com has one, but I don't know if one-size fits all. Then, do I use the factory size belt again?
There is an Aeromotive #21102 that is 32% overdrive.
Moroso also has a #23558 that can be made in different sizes.
I'll have to contact SLP to see if they can suggest something.
Any feedback is appreciated.
I got the car back from the dealership yesterday. It would not start after driving about four miles. Click, click, click went the starter. Then, I left the car to cool about ten minutes and it started up. The dealership replaced the alternator and starter. Still, I wonder if heat is somehow affecting the starter. It's strange, because this is a new problem with the car after it sat during my deployment.
Still, I would like to know more about the oversize alternator pulleys. Jegs.com has one, but I don't know if one-size fits all. Then, do I use the factory size belt again?
There is an Aeromotive #21102 that is 32% overdrive.
Moroso also has a #23558 that can be made in different sizes.
I'll have to contact SLP to see if they can suggest something.
Any feedback is appreciated.
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I have a SLP under drive pulley. I run a 10in sub, all the nitrous electronics and A/C and I've never once had a problem. My car is an automatic. I have an Optima red top battery though.
Originally Posted by Gregory
Is this an example of why GM is losing market share?
Originally Posted by MeentSS02
GM certainly lost my business due to their dealerships always giving me the runaround. Their dishonesty is the only thing I consider to be second to none. I won't even let them think about touching my Camaro anymore.
did you even complain that they fixed nothing and made you pay for parts it did not need? I work at a dealer and I can tell you if you talk very nicely and ask why you needed to buy these parts and yet you have the same problem they will either give you most if not all of your money back or make sure the car is fixed for no extra charge above what you already paid.
but you may also need to provide them with the stock parts so they can make sure it operates as gm intended. ALSO make sure the service writer knows and writes the SPECIFIC problem on the repair order. you would not belive what they will tell the techs.. its really a game of phone
