I have a '99 Cougar. When I got it, it came with an engine and transmission and accessories from my friend's Cougar (gamiller on NECO) that had no warning lights. When the drivetrain was installed in this one, I got a battery light at high RPMs. I replaced the alt. with a rebuilt one and the light was then on *all* the time. Great! Now what? So, I tested it. It read 14.2 volts at the peak and even when idling, so I assumed it was O.K. but I was getting the classic pulsing problem at the same frequency under all conditioans at all RPMS. What might be a factor is that the pulley on the new alt. was smaller than the one on the older alt. I am assuking that the old alt. had a stock pulley on it. Well, that rebuilt alt. literally fried this past week. I tested the voltage and got 12.23 with the car off and 11.68 with it running, which indicated the alternator was dead and the car was running entirely off of the battery. I just pulled it and got it replaced under warranty Sunday and did "the big three" with 2-gauge wire as well as a breaker instead of the megafuse. Everything runs fine at idle and below 5K RPM, but, at approx 5500 the battery light starts to blink and is on solid by 6000. I am assuming that, first, I need to get the stock sized pulley back on there and that, second, maybe the rebuilds from this place (Advance) could also be the issue. I understand that Ford used to have the alternators rebuilt by a certain company (I don't know which) and they frequently had issues at high RPMs and subsequently they switched to another company for their rebuilds. I could keep going back for replacements under warranty until I end up with one that works (which many on NECO have done), but that's a pain. Anyone out there had this same issue and fixed it in a different way? I know most say this is the sign of a dead alternator, but, it's a fresh rebuild, which does not count that out, but, given the pulley size difference, I am figuring that if it makes the right voltages at say 5500 or so, then a reduction of rotation of maybe 20-30% would clear up the issues. I am wondering if that is the difference between the pulley that was on (stock?) there vs. what is on there now(smaller)... Also, are some cars more sensitive to the signal from alternator than others? If so, is there a way to adjust or address that? Does anyone know of other compatible pulleys that can be used? I'd rather just drop the alt. speed a bit (under-drive) and leave water pump and AC the same for proper cooling and cold AC when summer comes back around. I've seen a posting for an under-drive set of pulleys (P/S and alt) on NECO, but that's kinda pricey.
At this point, I am inclined to get a larger (possibly just stock) pulley on there and, if that's not enough, get a bigger one or resort to an under-drive crank pulley. I mean, there's no killer stereo in there and if it's othewise keeping the battery (BTW, also new) charged, I figure it can't hurt to slow it down a bit and make it last longer.
Any suggestions and input welcome!
Thanks!
At this point, I am inclined to get a larger (possibly just stock) pulley on there and, if that's not enough, get a bigger one or resort to an under-drive crank pulley. I mean, there's no killer stereo in there and if it's othewise keeping the battery (BTW, also new) charged, I figure it can't hurt to slow it down a bit and make it last longer.
Any suggestions and input welcome!
Thanks!