Did the link work?

 

Looked at it yesterday

 

Yes, I have it. Thanks much. I also found the multipart manual, but I like this one much better.

Do you think the valley hose and the knock sensors can be accessed through the front of the intake manifold by removing the throttle body and the unnamed part in the illustration below?

It might (should) be easier then removing the entire intake manifold which I have done on a 2003 X308 and was bear of a job.

Thanks again and best regards, Brian

 

Bringing this discussion back up, as I'm preparing to replace the cooling hoses on my 2009 XF, with this 4.2 engine. I asked my dealer to supply me with all the hoses, and they included the AJ811111763 hose assembly, that's mentioned in this discussion. It took some investigation to find where it goes, and while it seems that heat, over time, would deteriorate this hose, if I have to remove the intake manifold to replace it, it's a lot of work, to say the least.

 

When my 'Valley Hose' leaked it was a rubber cooling hose that went in under the Inlet Manifold, turned 180 degrees and came back out, came up a little and then into my Throttle Body? Nothing to do with my heat-protected EGR hose (which enters and exits on the opposite side of the valley)?
I do not know whether or not this hose can be replaced through a 'slot' created by the removal of the Throttle Body?
IMHO (for what it is worth), I would not replace this Throttle Body cooling hose unless and until it is actually leaking.....
When it does leak it is very obvious because it runs coolant down from the very back of your engine, puddling behind the front wheel. The leak (in my case) was nowhere near catastrophic (risking engine damage with our poorly functioning coolant temp gauge). It simply leaked a little and gave plenty of warning of a problem.
Others may have a different opinion, but I hope this may be of some help?

 

The hose is ten years old, and a known problem on the X350. Not sure on the XF, but if you have looked at the service manual and your engine layout and the procedure is the same as the X350 and you are competent I would tell you to change it. You are doing them all - do them all now and forget about them for another 10 years.

I did mine on my 2004 X350, but did not remove the intake as I did not want to mess with the hoses in the back of it and if I recall I didn't touch the fuel injectors. I removed all the front parts as I was doing the thermostat also - I removed all the intake bolts (holding part #6 above) so the intake would lift off if the rear hoses were not still attached. I don't recall if I had to touch the fuel line, you will know as you will not have enough movement and it will be the cause. I then just tilted the intake at the front enough to get to the hose - back stays down. If you have an extra pair of hands to help the person can hold it while you work. I used a block to hold my tilt. It was not difficult at all - well worth the added 40 minutes. I replaced the gasket on both sides, by holding it up and working the back first, lifting just has enough to create the room to slide it in and bend the little tabs that hold the gaskets in place.

Hopefully this will work on your car.

 

Did mine while the intake manifold was off, to replace the eight rubber gaskets inside of it.
So i did not even look, to see if it could be replaced that way.
Mine was still in good shape, and was not leaking.
Butt was replaced, so it could be forgotten.

 

Thanks for the info....Had I been aware of this hose, I would have replaced this past fall...………….when I replaced the thermostat housing/coolant crossover pipe!!

When you see "buried" components like this, that are made of materials that will break down over time, you can't help but wonder, "What the hell were the engineers thinking"?? I'm old enough to have worked on late 60s Ford and General Motors cars, that had 2 hoses from the engine to the heater and 2 hoses from the engine to the radiator, and ALL of them were readily accessible. I know that for some reason, cooling systems have gotten more complex, but even my 2001 Corvette's hose layout, as complex as it has become, is accessible without having to remove any components from the engine, in order to swap out any of the hoses. And in the case of the Corvette, I was able to buy a set of molded silicone hoses, which should last a lifetime.

 

That is the beauty of this forum. Isolate your problem and see what else fails that is nearby. I bought my car with 84k on it and started researching what needed to be done. Coolant hoses and thermostat were on the of the list. I took a look and sure enough my thermostat was starting to fail so I ordered everything nearby so I only had to do the work once. Hopefully I won't have to go in there for another 5 years, assuming I still have the car. My hose was in good shape, but for the added time and minimal cost of the hose I am of the mindset to change it out and be done. I like working on cars once, figuring out how they are designed and assembled (whether idiotic or not) and fixing the problem. I hate repeat work as I learn nothing. I got rid of my Range Rover because I kept having to fix oil leaks every five thousand miles. All I learned was how dumb the design was, what brands of parts are sub-par and the source of the cheapest parts -- I am not interested in any of that. So far the Jag has been running fine, the suspension is about due but still is working with the original bags. I did all the front suspension parts, using the Lincoln LS equivalents I learned about on this board and had the transmission filter and oil serviced, also using Ford's fluid rather than ZF.

 

Great picture, and thanks for posting it. As previously mentioned, I'm preparing to change out all the coolant hoses out on our 10 year old XF, with this 4.2 engine. I have a very good relationship with my local Jag dealer, and I spoke with a couple of their techs, yesterday. They assured me that unfortunately, the intake has to be removed, in order to access the hose that this discussion is centered around. However, I didn't really pay close attention to this diagram, before speaking with them, so I didn't notice that the intake is basically 3 parts; the composite "upper section", and the two alloy, "lower parts"

For me, this brings up the question....Obviously, at minimum, the upper section has to be removed, to access this pesky hose, (which, by the way, the techs told me is the one hose in the system that usually goes bad, due to heat). However, looking at the diagram, it appears that the mounting bolts are long, and pass through both the upper intake, as well as the lower parts. For those who have done this job, A) is this indeed true? And B) if so, are those lower manifold components likely to shift around, during this process, therefore requiring replacement of those gaskets too?

Thanks!!

 

JUST AN UPDATE.....I replaced all of the coolant hoses a couple of weeks ago. Yes, the intake has to be removed, to get at that pesky, "buried" hose. And while not all that difficult, it is a tedious undertaking. The "experienced experts" say that this task takes about 3 hours. For me, a "first-timer", it took more like 5 hours, but I have to admit, I wasn't rushing, either. In essence, after removing and tying back the main "wiring bundles", on each side of the intake manifold, un-plugging several electrical connectors on the top side of the engine, as well as removing the throttle body and EGR valves, you can then remove the 10 long bolts that hold the intake to the engine, and both the upper and lower intake manifold sections will come off the engine, as a unit. However, at least on the XF, you'll also have to disconnect a vacuum line that becomes accessible, once you get the manifold partially dislodged from it's location. This line is at the rear of the manifold, crammed in between the intake and the car's firewall. When re-installing the manifold, don't forget to re-connect this hose before getting the intake completely back in, as once the manifold is in place, you can't access this.

The following day, I completed the job of replacing the remaining hoses in the cooling system. What a "bundle of snakes" that deal is. The job was made more difficult by a couple of hoses that connect to the engine's oil filter housing. I assume these are there to warm the oil in winter and cool it in the summer, but the orientation of the clamps, as well as the lack of work space, made this difficult and time consuming.

In the previous post, I asked about the lower intake manifold components "shifting around", during this process. As it turns out, those two pieces are solidly bolted in place, connected to the upper intake by bolts that are accessed on the underside of the upper intake.

 

Can the hose AJ811763 be replaced while the thermostat housing is off or just the intake?

 

My intake manifold needed to come off so while there i replaced the hose.
Replaced the thermostat housing assembly, & water pump, later on.
Close quarters under there as i remember.
It seems i read that loosening the bolts, then tilting the manifold up, will give you enough room to remove.

 

I think I'm just going to do the intake manifold gaskets and also the thermostat housing as it isn't much more work. I'm going to replace all the gaskets for the throttle body and EGR as well. I've ordered three different coolant hoses that are pretty common on the 4.2. is there anything else that I should do with the manifold off? What about the thermostat housing?. The car is a '09 XF 4.2

 

DON'T FORGET those eight hidden intake manifold gaskets.
That is why mine had to come off in the first place.
The check engine lite kept coming on.

 

Do you have a part number handy?

 

4526549

 

I found the set of 8 for a Lincoln LS for 69.00. They're the same, so are the intake manifold gaskets, although the Ford gaskets are about half price the of Jaguars. Paying for the name as they say!

 

Here are the eight hidden gaskets on the intake. I actually did not have the green ones with the black tabs on the sides. unfortunately I already ordered the green ones and had to order these ones so now I'm just waiting. Land Rover lr006678

 

Are you sure about that? I removed the intake manifold from my car, as a unit, with the lower "runners" of the manifold still in place, and untouched. I reinstalled it "as is", replacing the metal gaskets at the cylinder head/intake manifold interface, and it worked out just fine. IMHO, by removing the lower runners from the assembly, in order to replace the 8 seals, could possibly cause more trouble, as in most cases, you're disturbing a joint that is already well sealed, and functioning properly. As the old saying goes, "if it ain't broke, then don't fix it". If, HOWEVER, you positively know that you have a vacuum leak at that juncture, then yes, by all means, replace them.

One thing to be careful of, for those who are replacing the thermostat housing. On my car, that housing is retained by "button headed, socket head" bolts, not more common hex head bolts. The open end, or hex head of these bolts, face the front of the engine, therefore are able to collect debris, like what is generated from the serpentine belt, which then can fill the "socket" of the bolt. This makes it difficult to insert your hex-headed tool, in order to remove the bolt.

NOTE.....Before attempting to remove these bolts, be sure to thoroughly clean out the heads of these bolts, because if you "round out" the hex of these bolts, you'll play hell, trying to remove them, as they're partially obscured by other components.