The Rail Damper was leaking intermittently on my right side rail when engine was cold. After warm up, it stopped leaking and hard to find. Each rail has mounting cups same as the fuel injectors mounting cups. Checked the part in a sponsor website showed N/A, but checking for the 4.2L X-150 show a price of $193+ Part # AJ83838. Kinda stiff for a part not required for proper operation of the car. According to a Ford Master Mechanic friend, Ford quit using them for their system years ago. Our first thoughts were to remove the cups entirely and Tig Weld the holes closed. We chose this route and experienced difficulty in obtaining a leak free weld. The Rails are not 100% stainless, but a combo of that and another alloy. Finally we used a silicone Brass rod and got success. The Rail assembly is listed as N/L/A, do not want to scrap it. Faces with same situation, we would prefer to mill a plug the inside diameter of the cup and have it Silver Soldered to lessen heat and possibly flaking inside of rails. After we completed the welding, we did not flush the rails to clean any flaking and clogged 3 adjacent injectors on right bank. Purchased a Injector repair kit complete with screens, Pintle Caps (plastic piece on tip of injector fitting into the manifold holding lower O-Ring) and U & L O-Rings. The OEM Pintle caps are very fragile and break easily. Handle them carefully. Another option for repair is to just replace the O-RIng on you leaking fuel rail Damper . Others have tried but leaked later. Since the cups are same size as the injectors, one could modify* an upper tip 1(/2) of scrap injector, add new O-Ring and secure with a injector clip and have a secure deal also. The Upper O-Ring is larger than the lower that goes into the manifold. The trials we experienced revealed the Silver Solder method or possibly the modified injector tip would be satisfactory and leak free. The replacement of the Old Damper with new O-RIng is difficult due to the mounting method which requires one to bend tangs to free and then reshape to reseal. Hopefully this brief explanation will assist someone who encounters a similar situation.
BTY, The 7 Ingested Pintle Caps never appeared and probably vanished in the converters as they heated. Car runs great again w/o fuel smell.
*Modify. Open to individual methods, but the sealed upper 1/2 injector with new o-ring and clip should be viable option also. Seal it well!

 

Well done....

 

most dampers were moved internally into the rail, like GM has done for a long time.

there's benefits to be had from keeping them but who cares it's a jaguar lol

 

Do you have any idea what size the o-ring is on the damper. I've measured three of these and the OD average is 13.93mm so I think it a nominal 14mm. But, I don't know what the ID is..

 

It looks like there are a number of people advising on actions to solve the fuel damper leaks suggest removing them and blocking the port with a Soldered or Brazed plug. Does anyone have advice on the diameter of the plug to be used, it seems that the damper seal OD is nominally 14mm? Any advice would be appreciated.
Thanks.

 

The Damper is help by the Finger Type claws over the injector cup. The injector cups are all same ID size. You can use a Caliper to be the nominal ID and fab a metal plug for a snug fit. Rough measurement with cheap caliper is 13mm +-.. The metal will allow the solder to seal it and no more problems. I would hazard to guess a proper sized plug with JB Weld "solid cup fill" would seal also, but did not try. Clean the cup well prior to either method. Rail pressure would probably be 53-55#'s. The cups are all same ID as the injector with O Ring. My repair is great and no more leaks. Good Luck.