My XJS was sitting in the garage for years. Now I'm trying to get it road ready and my mechanic says fuel tank is full of gunk and rust. My options are a) find a replacement fuel tank on used market (very difficult) or have my tank cleaned (he can't do it). Has anyone here ever cleaned an old rusty tank or used a service to do that? Any advice?

 

Get the tank out and inspect it properly. Then post the extent of the problem for further advice. A few pinholes, for example, can be fixed by a radiator repairer spreading solder all obver the area. If there is fuel/liquid in it, then the holes cannot be too bad, if there at all.

 

https://www.gastankrenu.com/

I used that to reseal my existing fuel tank since there are no new ones available anymore. So far so good.