So I subscribed to Topix this week to get some information on fixing a few issues (valve cover leak and water pump replacement) when I ran across a procedure for the timing chain tensioner. I read through the entire procedure a few times and honestly, it looks somewhat straight forward. The big thing that struck me is that this procedure does NOT lift the valve covers to lock the cams. As a matter of fact, the only locking tool used is the flywheel tool. I don't see anything about removing the radiator or water pump. Pretty much the generator and the tensioners are all that get removed. The crankshaft pulley looks like the hardest part to remove in the whole process. The key to this process is the zip ties and only replacing the tensioner and guide. It's not a full-blown timing chain replacement guide.

Some items that made me scratch my head, they want you to remove the engine mounts in order to replace the fuel rails? Anyone know why?

Has anyone attempted this process?

 

Looks somewhat intimidating, just at the amount of parts that have to be removed, in order to gain access to the front of the engine…..

 

Leadfoot4 that's why they charge 16 hours labor.

 

I believe the fuel line runs under the rh engine mount. You probably can't snake the line through the motor mount because the small space is big enough for the line to fit but not fittings on the end of the line. I think the reasons for changing the lines is to 1 avoid leaks if the old ones won't reseal and 2 bending metal lines out of the way could lead to it breaking. Being its the fuel system I believe Jaguar is covering its bottom and the dealers while performing the service to avoid leaks, fires and irate customers. But who knows that's just my guess.

 

Has anyone one the forum actually used this method successfully?

 

Sounds logical, IMHO.

 

Yeah but I don't know that it's 16 hours... I'm tempted to give it a shot.. If I do I will try and document the whole thing.

 

So I did some research on this. The industry standard is to recommend high-pressure fuel lines every time you disconnect. HOWEVER, most people do not do this and there has been some research that states it is completely safe to resue once. The issue with reusing is really around getting a good seal when tightening to the correct spec. Every time you lose and tighten it changes the fitting where it can be more prone to leakage.

When I do this, I will leave them on and watch for leaks.

 

Good question... I was hoping for some feedback from anyone that might have tried this. I've only heard of folks replacing the entire timing belt but it looks like it may not be required..

 

From the invoice he posted on another thread it sounds as though this method was used by the dealership on XJsss’ car.

 

The only draw back to this method is that you cannot verify that the timing is perfect. But since you are not removing the chain from any of the sprockets, in theory, even if something moves, it would still be in time. This is not an option if your timing jumps.

Removing the valve covers is a real pain. If you have a supercharger, it has to come off first. It also requires removing the fuel rails and injectors.

I have not had any trouble getting the high pressure fuel lines to seal after they have been disconnected. They are very rigid so bending them out of the way slightly takes quite a bit of force. You would have to really pry on then to damage them. They are stainless steel.