I have been called out of town short notice. I have to drive my 2005 Super V8 about 1500 miles. The serpentine belt that runs the supercharger is ok but not new. The water pump belt is new. If the supercharger belt goes bad during the trip and I cant locate a replacement right away will the car still run in reduced power? Is it harmful to drive any distance this way?

 

I haven't looked on a SC'd jag, but on the eaton superchargers that my miata customers loved to install for some oomph, you could just tie (with wire, or ziptie) the bypass open.
Nothing harmed.

Does the eaton on the jag have an external bypass for off throttle/cruise situations?

 

No need to do anything and the car will run fine.

I have a 2005 STR and had a SC belt idler pulley lock up and then spit the tensioner out. I heard the noise but could not tell what was going on as I had no lights or other funny noises after the initial wham, bam, thank you ma'am.

But man was the car gutless! Got home and started looking and found the SC belt torn in two! It got wrapped around something and I am just glad no cooling hoses were taken out because there are a bunch at the front of the SC 4.2L engine.

Took me about a week to get the parts and drove every day. Just down on power and gas mileage.

The only thing I would recommend is if you think the belt is in danger of breaking just take it off before it does. I could have had a really expensive repair depending on what the belt might have taken out.

The Jaguar SC 4.2L engines do have a bypass but no need to mess with it.
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