I am in talks about a 2006 XJR with 139000 miles on it.

What things should I look at before agreeing to purchase?

I currently drive a X308 as my daily transportation.

 

Right off the bat at 139,000 I would hope that the transmission fluid has been changed a while ago as well as the supercharger oil.

Many other parts should have been replaced by now as well so I hope you have access to maintenance records.

Of course the air suspension, as you will see in this forum, is problematic for some owners. If this car has the original shocks then they are at about the limit or even past it .

Same for all the suspension bushings.

At this mileage I would expect to see prior replacement of the shocks and even the compressor.

 

Thanks! I also saw and printed out the sticky on X350 & X358 cars. Lots to read up on before I "talk turkey"

 

And the "Valley Hose"

 

+1 on that and all hoses.

The other issue that is not discussed a lot is the charge coolers being clogged.

Everyone on this forum that have taken the SC out, for example to replace the valley hose, comment on how dirty the charge coolers are.

Mine were pretty bad when I took the SC out at about 104,000 miles.

Part of the reason is that the high load breather connection feeds a considerable amount of oil from the crank case into the elbow below the throttle body and then through the supercharger which then pushes everything through the charge coolers.

The single previous owner of my car I believe always used premium and I use Shell premium whenever I can.

Despite that look at the pic of the elbow I mentioned above and then imagine that carbon in the fins of the charge coolers.

Thats why I now run with two oil catch cans. One on the high load and one on the low load breather lines.

The larger of the two hoses at the bottom right of the elbow is the feed from the high load breather.

 

This will be my first exposure to a supercharged engine.

The valley hoses don't scare me as I changed them on my X308.

Where are the Charge Coolers located?

What dissipates the heat? Is it water cooled with engine coolant? Air cooled?

 

The charge coolers are either side of the supercharger and covered by the red heat shield in my signature pic.

They are coolant cooled with an electric pump that is on constantly.

There is also a separate radiator that the coolant flows thru in and out of the charge coolers.

 

This is a pic without the cover.

Thanks to Windows 10 I had to reset the system which then lost all my Dropbox pics which I had to reload. Lesson learned about Dropbox!

 

jackra_1: can you tell me some more about the two oil catch cans you now run?

 

mikebaker3 there are two feeds releasing pressure build up from within the crank case which apparently is "worse" for supercharged engines.

One on the cars lhs and one on the rhs.

The one on the rhs is the high load breather that works when the SC is under load and the other is the low load breather that works when there is no load on the SC.

Both feed into the air intake system with the high load feed going into the elbow right below the throttle body.

I believe that the high load feed is primarily the cause of carbon build up in the elbow as well as in the fins of the charge coolers. Using the best quality fuel simply does not prevent this build up.

In the engine compartment of my 2005 XJR there is not a lot of room.

I installed a standard, baffled, oil catch can in the high load breather line which actually dripped oil when I took it off. On the low load side where there is even less room, I installed a smaller "Corvette" style catch can where I think the problem is less severe.

I have not run the car much since installation as I have had supercharger problems that started when I decided to replace my valley hose.
I figured that I might as well get a supercharger rebuilt with performance enhancements while I took the original one off.

I bought one on Ebay that I had rebuilt. Problem was that a new bearing went within a 1,000 miles on this rebuilt supercharger. So I have reinstalled my original and will rebuild the "rebuilt" one myself.

Anyway the jag was laid up for several weeks in total during this fiasco exercise.

 

I also installed an additional intercooler radiator to help with extra heat generated by a faster spinning supercharger as well as an upgraded IC pump.

I added two 6" pusher fans on that radiator.