Hi, I'm a newbie. I recently purchased a low mileage '02 XK8 convertible and I'm trying to take care of some long overdue maintenance. I'd like to replace the original heater hoses that travel under the intake manifold but it's not obvious how to remove the intake. I'm looking for help from someone who's actually removed the intake from their 4.0L XK8.

When I purchased the car the 'spider'/'octopus' heater hose was leaking and I when I attempted to replace it I was unable to remove the hose from under the trans tunnel. I was encouraged by members of another Jag forum to replace the hose but when I asked for help in getting the heater hose out from under the trans tunnel I was stunned to find out that none of the other members had ever attempted it. So much for 'enthusiasts'. Fortunately I didn't cut the hose ends off the car (except for the exotic plastic hose clamp behind the passenger's side head that was leaking) and was able to reattach the hose ends so I could drive the car to the shop for repair. But I was very disappointed that I wasn't able to rely on the Jag members of the other forum for help when I needed it.

BEFORE I screw up something on the intake I'd like to make sure I know what I'm in for. So if anyone who's REALLY removed the intake from their car is willing to direct me I could use the help.

Thanks in advance.

 

The inlet manifold on the AJ26 is relatively easy to remove using common hand tools. To disconnect the fuel line connection, you need a special tool, which is available from most local parts houses.

Be careful with the electrical connectors and breather hoses as they can become brittle with age and break.

Replace the inlet manifold to cylinder head seals and the gaskets for the throttle body to inlet manifold union.

If it hasn't been replaced already, replace the water outlet pipe and the thermostat housing as they can only withstand a finite number of cold to hot to cold cycles before the plastic fails. The thermostat housing can be replaced with the aluminium version to eliminate that cooling system failure point. Use an OEM thermostat instead of any aftermarket ones and be sure the bleed hole is in the correct position inside the cover.

Reassembly is the reverse of disassembly.

 

Remember to post an introduction in the New Member Area.

Here is a link to the earlier X100 Workshop Manual:

https://www.dropbox.com/s/fok2shk4eg...al_4L.pdf?dl=0

The procedure is similar with the AJ33 fitted to the later cars.

 

Thanks, I think. When I removed the throttle body to get at the 'spider' heater hose I noticed lots of bolts for the plastic intake facing the throttle body. Do I need to remove the throttle body again in order to remove the intake?

I have several of the fuel line removal tools so as long as I have one that fits I should be good. I have new radiator hoses & a bypass hose. I'll replace these after I get the intake hoses replaced. I'm not sure if I'll replace the plastic radiator hose housing/coolant temp sensor housing at this time. I know it's plastic and will crack in time but it's easy to access so I'm in no hurry to replace it. Same with the thermostat (I think). The heater hoses under the intake are trouble though. They're 20 years old and I'm told that if they start to leak they'll trash the knock sensors. So I'd like to get them replaced now if I can. If I can't get the intake manifold out of the car I'll have to take it in to a shop to have it done. I'd much prefer to perform the work myself. I'm just made that way.

 

Since you say your vehicle is a 2002MY, is it fitted with the 4.0 litre or 4.2 litre engine? The engine change was made in the later part of 2002.

Take time to review the Workshop Manual and become familiar with the procedure.

Here is a link to the AJ-V8 engine course:

https://www.dropbox.com/s/vqpy3bbjzd...e_168.pdf?dl=0

 

You do not need to separate the throttle body elbow from the plastic intake (the bolts you mention), but you do need to remove the throttle body. There are two triangular brackets underneath it that hold the elbow to the block. There are some bolts to be loosened/removed to allow the intake to be lifted with the elbow still attached (I'm pretty sure that this is all in the manual).

Member srpope80 posted a lot of pictures when he did this job. Lots of information in these two threads, including part numbers. Note they're for the 4.0L engine:

https://www.jaguarforums.com/forum/x...5/#post1939766

https://www.jaguarforums.com/forum/x...1/#post1975355

Unless you do have a 4.2L motor, I'd heartily recommend replacing the plastic thermostat tower with an aftermarket aluminium version while you have the intake off. It's so much better than trying to get at those two rearmost bolts with the intake still in place.

Also, get yourself one of these if it's not already in your tool inventory. It will make life generally easier, particularly when you come to replace the lower radiator hose:



Good luck and take your time. It's laborious rather than difficult.

 

Thanks, the images will be a great help. I have the 4.0L. The car already has the aluminum Thermostat Housing. I've tried the hose clamp tool depicted above but I'm not impressed with it. It works great on clamps where you can align the tool jaws across the clamp when you have to get at the clamp from the side it's no use. And this is most of the time. I find that a variety of channel lock pliers (slip joint pliers) work better.