I notice on a cold start a little more noise (slightest hint of a rattle, sort of a whir very, very slight) from the supercharger, which dissipates once I start driving. All my tensioners have been replaced, btw. I'm sure that's everyone's first thought. With a stethoscope I can tell its the SC. Do keep in mind it is very slight; I can only tell if I happen to have my window down or door open when I start it... obviously a bit more when the hood is opened up. I'm just more sensitive to noises so I picked up on it.

I've been told by 2 indies that work on Jags its pretty normal. You can change the oil in the SC but can only do it right if you pull it.

I'm just chalking it up to normal activity for a cold S/C with 10 years and 85,000 miles on it unless you folks say otherwise. Rebuilds seem pretty reasonable so I'm not going to worry about it.

 

You can check nose bearings for wear by removing the belt off the S/C pulley and turn to and fro to see if there's excessive play before engagement. A little is ok. There's a debate on here about servicing the S/C - you could change what you can in the way of fluid. A worn S/C will make more noise when coming off power, gentle rev and release the throttle, if worn it will emit a quiet chatter. 85k isn't generally an issue to these Eatons.