Out of curiosity, what is the pipe that links between the two inlet manifolds on the 5.3 V12 H.E. in the XJ-S? I see a number of hoses that lead into it and I'm guessing it's coolant but I'd like to know and none of the books that I have seem to mention it.

Part of why I'm asking is that I just noticed a hose that has a nick in it from (I think) rubbing against the air temp sensor and I'm wondering how urgently I need to have it replaced... right now or next pay period or... Anyway, what is it?

Thanks in advance.

 

Here's the hose,right over the left side air intake.

 

I think there light be a mix-up in your photos: First the steel pipe between the manifolds in your first pic:

This is the "suck" part of the positive crankcase ventilation system. The steel pipe across the two manifolds provides the suction. The steel pipe T-ing off it and running forward from it actually joins to the back of the B bank air box. If you look inside that airbox, you will see that there is a sort of sprung cartridge thingy that opens up under suction, and allows the crankcase fumes to be drawn into the inlet manifold down the tubes. The crankcase ventilation outlet is that big rubber round thing near the B cam cover oil filler:



The tube coming out of it is also joined to the front end of the B bank airbox. Worth cleaning the system out from time to time. There is a big gauze cannister filter beneath the round rubber thing, as well.

However, in your second pic, the tube with the nick in it seems to be running well forward of where the steel pipe from the manifold pipes joins into the back of the airbox. So I think that this pipe is something else, but I cannot tell what from the photo. It may, repeat may, be the fuel return pipe from the injection that leads to the firewall return pipe connection, though the routing is a bit unusual as this normally runs under the airbox. Can you take a look and tell us where each end of the nicked pipe goes to?
Greg

 

Sure. One ends up at a valve by the electric fan shroud that splits into two hoses, one of which disappears into the left wing.

 

The other end connects to a T junction, the left side of which connects to a part of the crossover pipe that travels forward rather than across the inlet manifolds.

 

Here is a photo of the cross over pipe (is that what it's called?). The section that points forward connects to the T junction shown in the previous photo.

 

That metal pipe is part of the crank case vemtilation - as has been correctly stated. I haben't got the other rubber pipes you have... That seems like some kind of separate kit...

 

Thanks for the pic. The hose with the nick is actually part of the petrol fumes containment/recycling system. (Daim, this is not fitted to UK and European spec cars.)

In the wing there is a charcoal cannister that is linked by a long thin pipe to the fuel tank fume recovery sytem (you can see the tank end of this if you look carefully at the top RHS of the fuel tank almost inside the flying buttress.).

Petrol fumes are sucked into the charcoal cannister, there is a Rochester valve in there somewhere too, and out of the cannister into the PCV system though the pipe you have identified. No need to worry about the nick! The system is described fully in the Great Palm's book.

Greg

 

Fantastic and fascinating. Thanks very much!