Just installed Mechman Alternator, Battery Light comes on now
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Just installed Mechman Alternator, Battery Light comes on now
So I recently bought a 240 amp alternator from Mechman Alternators for my 1998 GS300, now I have one problem. Every time my rpm's goes past 5k and I let off the gas my battery light comes on, I did not have this issue with my stock alternator. I have upgrade to 1/0 gauge KnuKonceptz Wire for my the Big 3 Three, although for my power run I have a 4 gauge run (I have no amplifiers yet, so I believe it won't draw the full the 240 amps but will pull stock load for now which is somewhere around 100 amps). I have copper lugs, an XS Power D3400, a new Goodyear Gatorback Belt, and also added an inline fuse. I have done everything that was asked and I still have a problem. Does anyone have any insight? I am wondering if it may have to do with the stock power wire being still connected and the fuse box being overloaded with power? I don't think that is the case, though not 100% sure, any information will help. I am also linking a video of the battery light coming on past 5k rpms.
https://www.youtube.com/watch?v=sI-Q...ature=youtu.be
https://www.youtube.com/watch?v=sI-Q...ature=youtu.be
Last edited by CharlieD93; 03-26-14 at 07:25 AM.
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I would go back with OEM like you say, but I am going to be running over 2000 watts in the next month and was told/also what I have researched, that a High Output Alternator would be needed to run all of that. That way I wouldn't have my headlights blinking, fry the OEM alternator, and have my amplifiers going off on me. But I do understand that OEM is always better, but will not work for my setup, thanks Flocko for being the only one to respond!
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The alternator is charging, so its not a dud. I sent it to Mechman 2 weeks ago and they fixed it and sent it back. It had a very loud oscillating sound that I knew wasn't right. I have another video to show there isn't any voltage spike when I let off at 5,000 rpms. So for it to still be a dud alternator, I would be very disappointed in there repair department. My voltage does fluctuate some between 13.3-14.2, whenever I turn on an accessory it just starts to plummet in voltage until I turn that accessory back off. I emailed Mechman and "they said it is a very strange problem but it sounds like you have it all wired up correctly." So my installation is all good, which would point back to the alternator, but I do not want to have to pay for shipping twice in 2 weeks. IF anyone has put on ANY aftermarket alternator on there GS and had the same problem or didn't have a problem at all, please let me know how to fix this.
#6
I had the exact same problem when i put in my 240a mechman alternator as well which was 2 weeks ago. I gunned it and the battery light would come on a for a split second. i had a half an inch shorter drive belt installed at the time and i thought that it was belt slippage at high rpms. I emailed mechman and they told me to look at the front face of the alternator where the pulley is to see if there was any black powdery residue build up, i swiped my finger across it and there was indeed a black powdery build up. So i went out a bought another half an inch smaller belt than what i already had on which makes my current belt 1 inch shorter than the original belt.
I'm not sure if that fixed the problem but ill hop in my car tomorrow and gun it to 5k rpm to see if i get the same results.
I'm not sure if that fixed the problem but ill hop in my car tomorrow and gun it to 5k rpm to see if i get the same results.
#7
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So I recently bought a 240 amp alternator from Mechman Alternators for my 1998 GS300, now I have one problem. Every time my rpm's goes past 5k and I let off the gas my battery light comes on, I did not have this issue with my stock alternator. I have upgrade to 1/0 gauge KnuKonceptz Wire for my the Big 3 Three, although for my power run I have a 4 gauge run (I have no amplifiers yet, so I believe it won't draw the full the 240 amps but will pull stock load for now which is somewhere around 100 amps). I have copper lugs, an XS Power D3400, a new Goodyear Gatorback Belt, and also added an inline fuse. I have done everything that was asked and I still have a problem. Does anyone have any insight? I am wondering if it may have to do with the stock power wire being still connected and the fuse box being overloaded with power? I don't think that is the case, though not 100% sure, any information will help. I am also linking a video of the battery light coming on past 5k rpms.
https://www.youtube.com/watch?v=sI-Q...ature=youtu.be
https://www.youtube.com/watch?v=sI-Q...ature=youtu.be
I had the exact same problem when i put in my 240a mechman alternator as well which was 2 weeks ago. I gunned it and the battery light would come on a for a split second. i had a half an inch shorter drive belt installed at the time and i thought that it was belt slippage at high rpms. I emailed mechman and they told me to look at the front face of the alternator where the pulley is to see if there was any black powdery residue build up, i swiped my finger across it and there was indeed a black powdery build up. So i went out a bought another half an inch smaller belt than what i already had on which makes my current belt 1 inch shorter than the original belt.
I'm not sure if that fixed the problem but ill hop in my car tomorrow and gun it to 5k rpm to see if i get the same results.
I'm not sure if that fixed the problem but ill hop in my car tomorrow and gun it to 5k rpm to see if i get the same results.
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Yes Sphan519 please let me know, I did try a smaller belt and it didn't help, but it wasn't a gator back like they suggested, I got a gator back belt that was for my car, maybe it is still slipping but I did get what they recommended. And spyder how much did you spend on the 270 amp dc power alternator? I just checked their website and they don't have our model car on their list, did they custom make it for me as well?
Last edited by CharlieD93; 03-26-14 at 05:40 AM.
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Spyder78, you think you could do the 5k rpm test for me? Just to see if it is the Mechman and not just all aftermarket alternators. I am pretty sure it is only with the Mechman alternator, but if you do that test for me and let me know your results, I would greatly appreciate it.
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That device you are testing for the voltage spike with isn't going to update the display fast enough to show a voltage spike or drop. To get a truly accurate picture of the voltage output at a specific RPM you would need to hook it up to an oscilloscope and watch. Same problem for people trying to get 02 sensor readings with a voltmeter.
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That device you are testing for the voltage spike with isn't going to update the display fast enough to show a voltage spike or drop. To get a truly accurate picture of the voltage output at a specific RPM you would need to hook it up to an oscilloscope and watch. Same problem for people trying to get 02 sensor readings with a voltmeter.