Hi, I have a Tuff Stuff performance chrome alternator in my 1993 Camaro Z-28. I have a fairly large electrical load, aftermarket tuner / cd player, 4 channel amp for the front and rear speakers, large 2 channel amp for the sub, power windows, power locks, ac, extra interior lighting etc. so I went with a 200 amp alternator. I have the 7864D which is Tuff Stuff's chrome version of a GM CS140 ZR1 200 amp alternator. It was put in by the shop that did a lot of work on my car and as such I do not have a receipt for the alternator or it would be covered under warranty by Tuff Stuff as it is less than 4 months old. The shop is no longer in business so that is not an option either.

It stopped charging about a month ago and I got a new voltage regulator from my local parts store and soldered that into the alternator and it seemed to be charging ok for about three weeks. Then I noticed the charge gauge was low but still in the "Good" range barely. While I was out and about that afternoon I noticed the starter seemed slow like the battery was getting low so I pulled into the parts store where I got the voltage regulator and they checked the charging system. The print out said the alternator was charging fine at some times and not at all others, charging off and on. So we looked up the 200 amp rectifier and ordered it. When it came in it didn't match and wouldn't fit in the alternator. So we went to the books to try and figure it out and the highest amperage rectifier they could get that matched the one in the alternator was 140 amp.

I couldn't get it there so I went looking for it on the internet at gm parts direct and other parts places. Unfortunately I still could not find a 200 Amp rectifier to fit my alternator all I could find was a whole new 200 amp chrome alternator just like the one I have. Does anyone out there have any idea where I can find the replacement rectifier or happen to know if this is even what would cause the alternator to charge off and on? The brushes are good as well as the contacts’ on the rotor and the windings look fine no burnt areas. The only thing I did find that was suspicious to me was what looked like arcing marks between the star washer of the battery post where it contacts the rectifier inside the alternator. The battery post and star washer look like they have been painted white on the inside of the alternator by the factory I am presuming but there is no paint on the rectifier or any other parts in the alternator so I believe the post and washer were painted before assembly of the alternator in the factory. Does anyone know if I need to clean the paint off the bottom of the star washer where it contacts the rectifier and if this arcing would cause the intermittent charging.

If it helps I can take photos of the parts in question and put them in here. The only numbers we could find on the rectifier are 501-067 YY7176 stamped into the part and 7176 printed on the part. Any help would be appreciated.

 

In a lot of area's there are shops that specialize in alt. rebuilds. Have you checked the "Yellow Pages"?