95 supercharger peeling

my 95 riviera had a rattle coming from the supercharger so i went in hoping it was just a bearing. it needed some small tightening done but the real problem we found was the teflon peeling from the turbines! it was coming off in rather large pieces and i was told that this would kill the performance of the blower. replacement part were impossible to find and we had to settle for a rebuilt from the dealer. at a thousand a pop, and thats a rebuilt (new ones are over 3k), id really like to find out what could cause this. ive checked for recall notices on it but got nothing. has anyone ever seen or heard of such a thing, on buicks or any other blowers? i love my rivi and want to keep her purrin, but im afraid this might be a manufacturing defect.

all the m90 eaton blowers do that after awile, it won't hurt a thing and performance won't suffer enough for you to notice, the coating is an epoxy to give a better seal and it peeling and going through the engine is just something that we have to live with, the noise was most likely the coupler in the s/c nose cone and can be replaced very cheaply with a new one from zzp performance, less than $50, m90 s/c can be bought used for about $250 on e-bay or in the want ads at regalgs.org or clubgp.com, rebuild kits are also cheap on regalgs.org, the 95 riv has the smaller m62 s/c and could have been replaced with a larger m90 for a nice performance upgrade for about 250 bucks, the stealer ships love to tell you there are no rebuild for the s/c so they can sell you a new one, i know this info is too late to help you but others may benifit from it

My mother-in-law's '95 Riv w/ 3800 SC is starting to make a rumbling/grumbling sound that seems to be coming from the supercharger. The car has 52,000 miles on it. How common is it for the coupler in the nose cone to go out on these engines?

Thanks!

all the m90 eaton blowers do that after awile, it won't hurt a thing and performance won't suffer enough for you to notice, the coating is an epoxy to give a better seal and it peeling and going through the engine is just something that we have to live with, the noise was most likely the coupler in the s/c nose cone and can be replaced very cheaply with a new one from zzp performance, less than $50, m90 s/c can be bought used for about $250 on e-bay or in the want ads at regalgs.org or clubgp.com, rebuild kits are also cheap on regalgs.org, the 95 riv has the smaller m62 s/c and could have been replaced with a larger m90 for a nice performance upgrade for about 250 bucks, the stealer ships love to tell you there are no rebuild for the s/c so they can sell you a new one, i know this info is too late to help you but others may benifit from it