I have a problem with a leaking Fuel Rail Vibration Damper on my '03 XK8 4.2. Since this is the third time I've had this problem I'm looking to truly solve the problem as these dampers are now over $200 a pop when you can get them (SNG are currently showing the item as Special Order). When I look at salvaged Fuel Rails for the 4.0 car I don't see that they have the location for the damper. If this is correct that these cars didn't have a damper on each rail then I'm wondering why putting the 4.0 Rail on my 4.2 car wouldn't be the solution. Anyone who has experience (or thoughts) on this I'd like to hear from.
Another alternative would be to replace the O-ring seal on the current damper; is this the same size as the O-ring that seals each injector to the Fuel Rail ports. Again, anyone who has experience (or thoughts) on this I'd like to hear from.

 

I would buy a set of O-Rings in various sizes and just see which one fits. You will save a lot of money in the long run. Just look for ones that can take being near fuel and ethanol. Viton is meant to be good. I don't remember what I used for my coolant leak but instead of buying a part from Jag I just got some assorted ones from Ebay. Been fine for 3 years.

 

From what has been shared on this forum, this is a tricky problem. Jaguar never offered these dampeners separately for our cars, but did for other models with the same engine. We were supposed to buy the entire rail as a whole assembly due to the difficulty of reliably fitting these dampeners without them leaking. And then the assembly quickly became NLA, leaving us without a direct fix option (if the cost involved even left the assembly as a true option). From the part#, I was once able to locate a vendor on eBay that sold reconditioned dampeners at a discount. Fitting them is reportedly tricky as they easily end up leaking. They supposedly have to be pressed in very square. These dampeners can leak at the seal (o-rings), but also through the body, prompting replacement. It seems like the injector o-rings are the same as for the dampeners. Or not.

Others weld plugs to the dampener openings on the rail, with various level of success. One would assume specialty TIG welding would be required, provided quality metal plugs can be obtained.

Complicating things is the difficulty of fitting the updated rail and testing it, only to possibly discover it leaking again. I am sure the supercharger is not helping matters in the least.

This is a frustrating problem, qualifying as one of the few remaining design flaws in our later cars.

Best of luck, keep us posted.

 

Attached is a link to my thread regarding the leaking dampers and successful repair. Not rocket science and easy to do with a qualified weld specialist..
The rail is not stainless steel but an alloy of metals and SS rods were not used. My repaired rails are working over 2000 miles and no problem. Dampers are redundant items. https://www.jaguarforums.com/forum/x...-leaks-256765/