Does anyone have a "how to" or any helpful hints on tightening the alternator belt on a XJR?

I know adjusting the alternator belt on a XJ6 is easy but the alternator on the XJR sits right underneath the supercharger.

I can't see the adjustment block with the supercharger in the way but I can feel it.

Does the supercharger belt need to be removed? What is the proper procedure for adjusting? Any idea what the adjuster bolt sizes are since I cant really see it? Is it easier to do from the bottom?

I have 14 volts of charging when cold but as the engine/belt warms up charging drops into the high 12 volt range. Even though it isn't squealing I figure the belt is getting loose as it warms up. Any thoughts?

Thanks

 

I would suggest reaching down to the belt and double checking the amount of play that it has before doing anything else. The voltage dropping off with heat is more indicative of an alternator problem than a belt issue, particularly when it's combined with a lack belt noise.
just my $.02.

 

Subject to correction by XJ6 experts, a drop in observed voltage is normal once the battery has reached full charge after a start.

 

Just replaced the alternator 2 weeks ago and when I adjusted the belt the supercharger belt was off and the electric fans were removed.

The voltage when hot is dropping to the point that the battery light will go on occasionally at idle and the volts will be around 12 +-. Once the rpms get above 1,500 the voltage goes right back up to the 14 +- range.